Journal of the African Cement and Concrete Industry
trends VOL 22 No 1 February 2019
Spotlight on the San Heritage Centre
Maputo suspension bridge, longest in Africa
Precast concrete, reliable and versatile
Forecasting the future of BIM
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CONCRETE trends
COVER Journal of the African Cement and Concrete Industry
trends VOL 22 No 1 February 2019
Volume 22 No 1 February 2019
CONTENTS
Spotlight on the San Heritage Centre
Maputo suspension bridge, longest in Africa
Precast concrete, reliable and versatile
Forecasting the future of BIM
Concrete played an important role in the new San Heritage Centre at !Khwa ttu near Yzerfontein in the Western Cape. Photograph courtesy of Daniel van der Merwe. See page 14.
Message from Gill Owens the editor . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Industry News . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5 Association News . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 News from Africa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10 Art & Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-15 Projects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-18
16 Battery Park is transforming the V&A’s Canal District.
Roads & Bridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-25 Reinforcing Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Readymix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Precast Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30-34 Cement & Concrete Technology . . . . . . . . . . . . . . . . . . . . . . . . . 36-38 Products & Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40-41 Digital Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42-43
THE LAST WORD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
20 Maputo Bridge: the longest suspension bridge in Africa.
VICE PRESIDENT:
EDITOR:
Devi Paulsen-Abbott e-mail DeviPaulsen@dmgevents.com
Gill Owens e-mail GillOwens@dmgevents.com
Elise Jacobs e-mail elise.jacobs@hypenica.com
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message from the editor
The darkest hour comes just before the dawn This familiar and overused proverb appears to have first been committed to print by English historian and theologian Thomas Fuller in 1640. And in the South Africa of 2019 one can only hope that it will prove to be true. There can be little doubt that, for consulting engineers and for the construction industry, the darkest hour is definitely upon us. Since the period of ‘Ramaphoria’ at the end of 2018, scepticism has become pervasive. That brief surge of optimism has taken a steady downward trajectory and the majority of the sector has lost confidence in any speedy implementation of the long-promised billionrand government infrastructure spend – despite President Ramaphosa emphasising the importance of infrastructure in boosting employment and economic growth. In his replies to parliamentary questions raised by the State of the Nation Address the President said: “We are at a moment in our history where we need to make difficult choices.” It is extremely hard for politicians to make difficult choices and those who do so often fail to be re-elected. It is only at times of crisis that politicians are courageous enough to make difficult choices and to implement necessary, but unpopular, measures. While there is no doubt that President Ramaphosa inherited a poisoned chalice, he has seemed slow to take the decisive
steps required to deal with rampant corruption at every level, to rescue and invigorate failing state-owned entities and to convince a population, shell-shocked by daily doses of bad news, that a new regime is truly in place. Thus, few will dispute the fact that South Africa, and particularly the construction sector, has reached a crisis point In a pre-election period, it takes a man of great courage to do the right (but difficult) thing to put the country on the path to recovery not only of its economy but also of its self-respect. The ability to make difficult choices is the one quality South Africa desperately needs in a leader right now. With the May elections firmly in our sights, it will soon become clear whether Ramaphosa has that quality and the necessary courage. Naresh Pather, Consulting Engineers South Africa’s (CESA) new president, has called for a collaborative effort between the public and private sectors to form a viable and positive movement to realise his vision of ‘Reshaping our future together’. This, plus political will, could make the difference and change the country’s future direction. It is my profound wish that it will.
Gill Owens, Editor
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INDUSTRY NEWS
Major wins for Flowcrete at the FeRFA Awards 2018
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lowcrete has won the Large Industrial Project of the Year and Large Commercial Project of the Year categories at the prestigious FeRFA 2018 Best Practise Awards. The Resin Flooring Association (FeRFA) represents major businesses and organisations involved in resin flooring, screeding and surface preparation. Its annual awards event, held in Solihull, UK on November 23rd, celebrates the past year’s best resin flooring projects. Kevin Potter, MD Flowcrete UK, said: “Winning two categories is a fantastic testament to the hard work and commitment of the Flowcrete UK team as well as the quality of our flooring solutions. “All the projects that made the shortlist are remarkable showcases of what can be achieved with resin flooring technology and we knew that we faced a stiff competition from across the globe. ”I can’t think of a better way to recognise what can be achieved when our products and expertise are combined with architectural innovation and by using only highly trained applicators.” Flowcrete was first presented with the Large Industrial Project of the Year award for its work at The Macallan’s stunning new whisky distillery. This was followed by winning the Large Commercial Project of the Year category for the Menai Science Park’s (M-SParc) Flowcrete floor. The Macallan’s floors, undertaken with applicator partner IFT, had to withstand the demands of high-end whisky production while providing a safe, visually attractive and on-brand finish. In addition, the application work took place at the client’s remote Speyside estate during a cold and blustery Scottish winter. Over 21,000 m2 of Flowcrete’s systems ensure that the floor in each part of The Macallan’s site was up to the task. This in-
cluded a robust polyurethane coating for the production areas, fast-curing and slipresistant floors for the main tourist routes, a high-gloss and shiny black epoxy surface in the cask room, a natural-effect stone carpet for the external perimeter as well as other assorted screeds, primers and coatings for the project. At M-SParc, it was vital that the flooring reflected the aesthetics and style of the site’s architectural concept. The applicator, Coatech, installed Peran Comfort in combination with Rustik Glamourstone to create a continuous ribbon of flooring that connected the outside areas
to the inside and emulated the building’s pure white external Corian cladding. The bespoke, decorative finish had to be completed within a very tight turn-around and in a busy site in the middle of the Anglesey countryside. The dedication and expertise of Flowcrete and Coatech saw the project finished to the client’s high standards and in time for the science park’s grand opening.n
More information from Tel: +27(0)31 461 3411 www.flowcretesa.co.za
Flowcrete won the Large Industrial Project Award at the FeRFA Awards 2018.
February 2019 CONCRETE TRENDS 3
INDUSTRY NEWS
Knight Piésold achieves the country’s transformation aims
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he multi award winning civil engineering consultancy Knight Piésold, has proved that it is possible to become a truly transformed multi-national organisation that embraces South Africa’s BBBEE imperatives as responsible corporate citizens. Having recently achieved Level 1 BBBEE accreditation through training and developing local staff and shareholders as
well as enterprise development and participation in meaningful CSI initiatives, the 97-year-old firm is a proudly South African company that invests its profits locally. Knight Piésold achieved Level 1 BBBEE and 57% black shareholding. The company’s shareholders are full-time employees, having grown and developed into leadership positions in the firm. Although smaller in size than its foreign-owned competitors, the company has significant global reach through its branch offices across the world. In 2018, Knight Piésold won fourteen awards from industry associations including Consulting Engineers South Africa (CESA); the South African Institution of Civil Engineering (SAICE) and the Institute of Municipal Engineers (IMESA). This is the highest number of awards won by a firm in 2018 and recognises the company’s excellence in engineering, business and mentorship. Vishal Haripersad, MD of Knight Piésold states, “We are proud of our transformational journey, we believe in the scorecard we have attained, we believe in empowering businesses and people, we have never
believed in buying shortcuts to transformation within our organisation, we do not see it as a mere cost on the balance sheet but as an imperative for the sustainable economic growth of the country.” Knight Piésold has focused on developing the next generation of South African engineers through investments in mathematics and science at secondary schools throughout South Africa. In 2019, Knight Piésold will make ten bursaries available to first-year Civil Engineering students. Haripersad concludes: “There is no shortcut to success! We are working with stakeholders that include the general public, business and government to create a culture of respect, performance and hard work. We have asked what we as an industry should be doing to create the future we want to see and have implemented the actions required to achieve this goal.”n More information from Tel: +27(0)11 806 7111 email: rivonia@knightpiesold.com www.knightpiesold.com/en
M&D Construction Group: 35 years of construction excellence
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&D Construction Group recently celebrated its 35th anniversary at an event attended by the company’s many clients, as well as supplychain partners and employees. Yolanda Sedibe, the M&D Construction Group’s human resources director, said it was fitting that such an important occasion be celebrated at the University of Witwatersrand’s Science Stadium considering the company’s long professional relationship with the institution. “This is where we first earned our reputation for being a specialist concrete contractor. Our Building Division refurbished and even completely rebuilt most of these stunning structures on campus. These buildings with their striking off-shutter finishes bear testament to the focus we place on ensuring the highest level of quality on all of our projects,” Sedibe said. The company’s motto of “Khula Nathi”, an isiZulu phrase which means “Grow with us”, spans our clients, sub-contractors and suppliers. It guides everything we
4 CONCRETE TRENDS February 2019
From Left: Andrew Murray, Co-founder and Chairman; Yolanda Sedibe, Human Resources Director and Rukesh Raghubir, Chief Executive Officer. do, and includes our loyal employees who have demonstrated their commitment to the company. More than 60 members of our team have been with us for over a decade,”Sedibe noted. Company co-founder and chairperson, Andrew Murray, stated that one of M&D Construction Group’s other strengths was
its diversity, reflected by the company’s client base, supply-chain and employees. He said that M&D Construction Group had made it thus far by its robust and resilient management team; sufficient cash reserves to weather tumultuous episodes; and by always focusing on servicing clients to the best of its ability. CEO, Rukesh Raghubir, said that management was confident that M&D Construction Group had a strong strategy to ensure that it achieved its target of becoming a R7billion company and was positioned to be at the forefront of technology and using innovation as a disruptor to the construction industry within the next 10 years. He reassured the company’s many clients that M&D Construction Group remained committed to maintaining the highest possible quality standards.n More information from Tel: +27(0)11 4631962 email: info@mdconstruction.co.za www.mdconstruction.co.za
Sanika wins prestigious ICRI Award of Excellence
A strong foundation for infrastructure success
Brian MacNeil, ICRI with Paul and Colte Smit of Sanika, the first South African firm to win the award in 21 years.
O
n the 9 November 2018, for the first time in 21 years, a South African Company won the Award of Excellence at the International Concrete Repair Institute (ICRI) Awards, held in Omaha, Nebraska, USA. The prestigious Award of Excellence was presented to Sanika Waterproofing Specialists for their very professional concrete repair and waterproofing of the Anglo American Coal mine ventilation shaft at Goedehoop Colliery in Mpumalanga. ICRI, which is an industry body comprising world-renowned engineers, architects, manufacturers and contractors, hosts an annual awards ceremony to honour and recognise outstanding projects in the concrete repair industry. It attracts over 50 project entries per year. This as a huge boost for the South African concrete repair and rejuvenation market as it has shown South African companies as a formidable force in the international concrete repair industry. With approximately 7,000 litres of water flooding into the shaft per minute through numerous cracks, some up to 300 mm wide, the potential safety hazard and possible failure of the structure, if left untreated, was indisputable and required an immediate permanent solution to be found to remedy the massive ingress of water. Numerous products had been tested and failed due to the enormous water pressure across the 9-m-diameter shaft. Few products or applications can be applied on the negative side against such pressures. Sanika’s professional expertise combined with Kryton’s Concrete Waterproofing repair and rejuvenation products, ensured successful waterproofing that stopped water ingress. Furthermore the structural integrity of the shaft was maintained and thus durability improved. The crystalline technology penetrates crystal growth deep into the concrete mass, transforming the concrete itself into a waterproof barrier and resulting in a dry, safe and useable shaft. Kryton crystalline technology can withstand 14 bar (140 m) of negative pressure, self-heals cracks up to 0.5 mm and drastically decreases water permeability of the concrete.n More information from Daniela Warne, Tel: +2 11 425 3061 / www.sanika.co.za
February 2019 CONCRETE TRENDS 5
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ASSOCIATION NEWS
Ash is the 21st century’s next big thing says SACAA
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ith a little innovation and a sound business plan any South African stands to make a fortune out of the millions of tons of coal ash produced by the country’s generators annually. With mountains of ash available at all of South Africa’s coalfired power stations, Eskom, Sasol and other smaller producers, there is no shortage of supply and anyone wishing to make use of the ‘Grey Gold’ is likely to get it at little or no cost provided they can prove that they have viable usage and that their operation will generate revenue and jobs. Already 10% of the total 50-million tons of ash produced per year is used in the manufacture of cement powder and concrete bricks for the building industry, as well as being used to treat acid mine drainage and remediate soil for agriculture and other land uses. However, experts have identified a host of other uses including alternative building products, volumisers for plastics manufacture, contouring for road, rail and landscaping infrastructure, and many of other uses. Entrepreneurs wanted
Now, with Government’s assistance, the South African Coal Ash Association (SACAA) has been given a target to increase ash usage to 20% of offtake and to create 26,000 new jobs within the next five years. In addition, start-up ash operations can expect assistance from Government, generators, SACAA and academics to extract the maximum potential out of ideas deemed to be viable. SACAA general manager, Mark Hunter, says the association is looking for industrial entrepreneurs to assist in identifying and developing viable business opportunities for the use of waste ash generated by producers. As the second biggest waste stream (after organic waste that is sent to landfill), coal ash is becoming a headache for the country as space to dump the ash is running out.
SOUTH AFRICAN COAL ASH ASSOCIATION He states that reaching the 20% target is not only possible, but probable if more viable alternatives can be found to dumping. This will require close cooperation between role players and speedy facilitation between Government and other role-players who also fully understand the urgency of the matter and will likely pull together to make it happen. Team effort “First, we need ash to be excluded from the classification of hazardous waste. Extensive research has shown that there are many applications of ash which are not harmful to the environment or health. Next, we will need to continue working with formal industries, such as mining, construction and the cement industries, to explore all possible avenues to utilise ash. “Simultaneously, we will also engage with scientists and entrepreneurs to identify areas where ash can be used as additives in manufacturing processes and as an end product. Then the race will be on to industrialise these and we will facilitate and assist in every way to make sure it is successful. “As a part of the Department of Environmental Affairs’ Phakisa program to reduce waste to landfill/ash dump/dam, as well as create sustainable employment, we are confident of Government’s full backing and that we will make a success of the project. We therefore call on creative, technical and business people as well as entrepreneurs, to come forward and be a part of the solution,” says Mark.n More information from Mark Hunter, Tel: +27(0)83 631 0793 email: mehunter22@icloud.com www.coalash.co.za
About the South African Coal Ash Association (SACAA) The SACAA is the official industry representative association for ash producers, marketers, users and individuals involved throughout the entire ash supply chain. Producer members include Eskom, Sasol and Kelvin Power station. Associate members include Ash Resources, Ulula Ash, Afrimat, Afrisam Cement, Kwikbuild Cement, PPC Cement, Sephaku Cement, NCP Cement and is supported by research organisations including the Council for Scientific and Industrial Research (CSIR), consultants and academics. Mark Hunter, general manager of SACAA.
6 CONCRETE TRENDS February 2019
Brian Downie inaugurated as 116th SAICE President
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he South African Institution of Civil Engineering (SAICE) inaugurated Brian Downie as the new President of the Institution on 29 November 2018. Downie is the 116th President of SAICE since the inception of the Institution back in 1903. He is a consultant with Royal HaskoningDHV, where he has held a variety of positions over the past 37 years in the Transport and Planning fields. Downie’s Presidential theme for 2019, It’s a New World, is focused on Education, Entrepreneurship and Employment – all vital issues for South Africa. The primary focus on education will be achieved by extending existing initiatives with the Department of Basic Education where engineers will offer tutorial support to Grades 11 and 12, utilising new technology – now with the resources of 12,000 members of SAICE in support of this enterprise. Downie states, “With the advent of smart phones, we are proposing an ambitious relationship with the Khan Academy (supported by the Gates Foundation) which will offer a set of online tools to help educate students. The Department of Basic Education already has the Khan Academy videos translated into isiZulu and isiXhosa”. In parallel, Downie is proposing a strategic technology partnership with The MakerSpace Foundation that currently works with people from all ages and backgrounds, leveraging disruptive technologies of the 4th Industrial Revolution, such as 3D printers, to help people make things that improve their lives and the world around them. Downie was chairman of the SAICE Durban Branch in the period leading up to South Africa’s first democratic elections. The Minister of Public Works subsequently appointed him to assist in forming the Council for the Built Environment (CBE). This culminated in the Council for the Built Environment Act (Act 43 of 2000). He served on SAICE Council for seven years and has been very active in a number of the engineering industry’s organisations. He is deeply passionate about the future facing the youth of South Africa as the Fourth Industrial Revolution becomes a reality. He believes we have a limited time to guide, educate and mentor young people in 21st century technologies.n More information from Nadeena Le’ Tang, Tel: +27(0)11 805 5947 / email: nadeena@saice.org.za www.saice.org.za
February 2019 CONCRETE TRENDS 7
NEWS FROM AFRICA
SOM breaks ground on Alárò City in Nigeria By Lizzie Crook
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onstruction has now begun on Alárò City, which is being master-planned by Skidmore, Owings & Merrill, as an extension to Lagos in southwest Nigeria. Designed by Skidmore, Owings & Merrill (SOM) for the Lagos State Government and city builder Rendeavour, Alárò City will be in the Lekki Free Zone to the west of the city. It is designed to boost foreign investment and create ‘tens of thousands of jobs’. Covering more than 155.5 square kilometres, the city will combine a mix of industrial and commercial facilities positioned in line with the ‘growth path’ of Lagos, one of Africa’s fastestgrowing cities. “Alárò City helps strengthen Lagos’ position as the economic and cultural hub for west Africa, by creating a new mixed-use
model sustainable community – a place for people to work, make, live, and learn, which aims to become an international trade gateway,” explained Daniel Ringelstein, director at SOM. While the south of Alárò City will be dedicated to industrial, warehouse and logistics facilities, intended to encourage innovation, the north side of the masterplan will host offices, homes, schools, hotels, healthcare and entertainment facilities, which are orientated towards Lekki Lagoon. All the facilities will all be positioned around approximately 150 hectares of parks and green space, which is divided into six ‘greenways’. These greenways will sit approximately 800 metres apart, ensuring that residents and workers will never be more than a five-minute walk from open space. Each area within Alárò City will be connected by a main boulevard, alongside a network of shaded, pedestrian-friendly streets and urban plazas. Central to the masterplan is a 14-hectare park that will be used to host community events. “We are delighted to be bringing our successful inclusive city model to Nigeria and Lagos State, the heart of the country’s vibrant economy,” added Stephen Jennings, founder of Rendeavour. “Our partnership with Lagos State will ensure that Alárò City is an economically sustainable city open to all Nigerians.” The expected date of completion is undisclosed, but SOM said that a number of multi-national companies are already building facilities on site. Founded in 1936, SOM is an international architecture and design practice with projects completed in over 50 countries.n Source: https://goo.gl/TmW7ih
NSE to address housing challenges
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he Nigerian Society of Engineers (NSE), has advocated to the government for coordinated efforts, including engaging of experts and proper planning of cities, in bid to address the rising housing challenges confronting Nigerians. According to Eng. Adekunle Mokaoulu, the President of NSE, issues of accessibility and right of use of land to develop housing schemes and corresponding capacity development were impeding the growth of housing stock. Eng. Mokaoulu noted that unofficial data put the country’s housing deficit at over 18 million housing units and he further pointed out that most of the subsisting interventions by the government in the housing sector favoured the elites. “Provision of critical infrastructure in the rural communities will go a long way towards boosting productivity and creating wealth. Iron and steel holds the golden key to the development of all other sectors including our automotive, construction and machinery industries among others. The steel sector of our economy can emerge as the highest employer of labour if revived,” said Adekunle Mokaoulu. Additionally, the NSE President said that the association will re-emphasise the need to prioritise rural integration in the approach to infrastructure development in the country. He also applauded the government’s move to commence inspections
8 CONCRETE TRENDS February 2019
of construction sites to ascertain the level of compliance with Executive Order 5, targeted at improving the local content in all public procurement. He explained that in Nigeria, it has been an uphill task getting successive governments to understand the importance of Indigenous engineering innovations to national economic and social development.n Source: https://goo.gl/2oyAFa
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NEWS FROM AFRICA
Nigeria: Executive Order enables private-sector road construction
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ith the signing of Executive Order 007 2019 by President Muhammadu Buhari to allow private companies construct and refurbish roads across the country, the two-year old Nigeria Industrial Policy and Competitiveness Advisory Council (Industrial Council) has chalked another landmark achievement in accelerating infrastructure development for economic growth. The Executive Order is a Road Infrastructure Development and Refurbishment Investment Tax Credit Scheme that enables the Federal Government of Nigeria to leverage private- sector funding for construction or refurbishment of eligible road infrastructure projects. It focuses on the development of eligible road infrastructure projects in an efficient and effective manner that creates value for money through private-sector discipline; and guarantees participants in the scheme timely and full recovery of funds provided for the construction or refurbishment of eligible road infrastructure projects through tax credits. This Executive Order is an initiative whose time has come because as industrialists in the Council expressed their willingness to intervene in road rehabilitation and construction in their areas of operation through a transparent process that ensures the cost of construction/rehabilitation can be recouped. The scheme is widely viewed by stakeholders who have been engaged in the public and private sectors as a quick-win in road construction and enjoys widespread acceptance as a means of accelerating growth within industrial clusters. In the pilot phase, six companies will construct 19 roads covering 794.4 km. The Minister of Finance, Zainab Ahmed,
who listed the roads at the signing ceremony, said the scheme is the outcome of efforts at innovative thinking and deploying new techniques to develop critical road infrastructure. The six companies to construct the 19 road projects for the pilot phase, totalling 794.4 km in 11 states across each of the six geo-political zones, are Dangote Industries Limited; Lafarge Africa Plc; Unilever Nigeria Plc; Flour Mills of Nigeria Plc; Nigeria LNG Limited; and China Road and Bridge Corporation Nigeria Limited. In his speech at the signing ceremony, President and CEO of Dangote Industries Limited, Aliko Dangote stated that, “The impact is huge because it will allow private sector to use their capital, their know-how and also their efficiency in terms of delivering roads in time and the Nigerian government will be saving billions of naira.”n Source: https://allafrica.com/stories/201902060347.html
Ghana Building Code is “major milestone for the country” says David Adjaye By India Block
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outdated regulations from the 1960s, hana’s first Building Code marks and National Building Regulations were a pivotal moment for architecture ratified in 1996. and construction in the country, The Ghana Building Code is a modisays Ghanian British architect David Adfied adoption of the International Buildjaye. ing Code. The 1,700 page document was Adjaye welcomed the first official Ghacreated by the Ghana Standards Authorna Building Code, which was introduced ity for the ministry of works and housing. at the end of 2018, saying it was a “high“The implementation of the new Buildly significant step”. ing Codes will most certainly establish Adjaye, who was knighted for services standardised regulations on quality, durato architecture in 2017, said there was a bility and materiality within construction an urgent need for a standardised set of practice,” said Adjaye. practices for architecture and construcAdjaye believes the introduction of “It is highly significant step towards the tion in Ghana. building codes is a pivotal moment. development of new, national infrastruc“Creating safer, more accessible buildings, Photo by Alex Fradki. ture programmes and sign of the progresresidences and infrastructure within Ghana sive nature of Ghana’s governance today.”n is paramount,” he explained. “One example is in providing earthquake resistant construction technology and practice.” Ghana gained independence from British colonial rule in Source: https://goo.gl/a9BJZw 1957. A draft code was introduced in the 1970s to replace
10 10 CONCRETE CONCRETE TRENDS TRENDS February February 2019 2019
African Construction and Totally Concrete Expos are powered by The Big 5 – the world leading building and construction event
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et against the current backdrop of improved optimism now that the South African economy has emerged from its technical recession, the African Construction and Totally Concrete Expos are about to break the records set in 2018. The 2019 expos, now under the hugely successful Big 5 banner, being held at the Gallagher Convention Centre in Johannesburg from 11-13 June, will be upping the ante. dmg events is bringing their expertise and experience to bear in building on existing knowledge sharing, networking and business matching opportunities, as well as using its wider reach to attract even more international visitors and exhibitors. With Johannesburg Mayor Herman Mashaba’s Inner City Revitalisation Project in full swing, there is, as he has said, “No better place in terms of real estate to invest in other than the inner City of Johannesburg in South Africa.”
Our stand has been getting bigger over the years: we brought more products and machines and by doing that we opened the doors to a bigger market. And Totally Concrete has opened the market for us. Colte Smit, Technical Sales Manager, Sanika Waterproofing Specialists Johannesburg is a city abuzz with projects: • The first three buildings in the Inner City Revitalisation Project have been handed over to developers, and the mayor promises to release 80 to 100 more buildings for redevelopment in 2019 to make a dent in the city’s 300,000-unit housing backlog. • The R2 billion Jewel City initiative will see property developers Divercity redevelop six blocks of Johannesburg’s CBD and the Absa towers main building, constructing over 2,700 apartments, a school, clinic, and gym. • The GM of O. R. Tambo International Airport, Ms Bongiwe Pityi-Vokwana, has held the sod-turning ceremony for major new developments on the airport’s Western Precinct. Investment of R4.5-billion will enable the airport to unlock the potential of 1,000 hectares of serviceable land in the Western Precinct. Opportunities for construction will encompass office and hotel as well as retail facilities.
In addition, President Cyril Ramaphosa’s recent State of the Nation Address announced that: • Increased emphasis is being placed on infrastructure development to support ambitious development plans for the country. • Government will inject R100 billion into the Infrastructure Fund over a 10-year period to leverage financing from local and international private sector and development finance institutions. • The Housing Development Agency will construct an additional 500,000 housing units in the next five years, and R30 billion will enable municipalities and provinces to fulfil their respective mandates. • A Human Settlements Development Bank will be established to leverage both public- and private-sector financing to aid in housing delivery. • The People’s Housing Programme will be expanded; households will be allocated serviced stands to build their own houses, either individually or through community-led housing cooperatives.
Five years ago the Conchem brand was not very prominent, but now, thanks to the African Construction Expo, people know who we are and what we do. We walked away with 13 serious enquiries. Graham Smith, Sales and Business Development, Conchem • S tudent accommodation projects around the country are being accelerated. • Government will work to remove constraints to greater investment. Already a high-level multi-departmental team is working to eradicate policy, legal, regulatory and administrative barriers that frustrate investors and make doing business in South Africa easier. In addition to the South African market, McKinsey’s new book, Africa’s Business Revolution: How to Succeed in the World’s Next Big Growth Market, sees Africa poised for economic acceleration, akin to the Asian boom.
12 CONCRETE TRENDS February 2019
From very extensive research and interviews with Africa’s most prominent business and development leaders, McKinsey sees a trillion-dollar opportunity to industrialise Africa to meet its rising domestic demand and to create a bridge-head in global export markets. Investment opportunities abound and the African Construction and Totally Concrete Expos – powered by The Big 5 – will bring together stakeholders at every level to identify and exploit opportunities.
This is a tremendous show in a great emerging market. We got over 100 customers, not just from South Africa, but also from West and North African countries. Aniruddha Banerjee, Senior Manager, KHK Scaffolding & Formwork LLC, United Arab Emirates This year, for the first time, the African Construction and Totally Concrete Expos will be co-located with Pumps, Valves and Pipes Africa. This new co-location will bring PVP sector’s players an even bigger platform for the industry to do business, a much bigger audience, many more growth and new partnership opportunities within a broader spectrum of industries. Currently, the Internet of Things (IoT) and Big Data are accumulating decades of knowledge and connecting billions of physical devices around the world to collect and share data. These technologies will ensure better visibility, forecasting and maintenance planning. Pumps, Valves & Pipes Africa 2019 will be showcasing some of these technologies along with many new products.
We got invaluable leads, including key stakeholders from Eskom and other large corporates that are not easy to reach. At the expo, they come to us. Tracy Harris, Commercial Manager, Mapei South Africa Together with Pumps, Valves and Pipes Africa, the African Construction and the Totally concrete Expos will be offering more product showcases with free-to-attend strategic and technical workshops that will be more interactive with revolutionary case studies and interactive panel discussions. The dynamic programme has been designed by the industry for the industry. Last year the African Construction and Totally Concrete Expos attracted 8,016 construction professionals, showcased 3,243 participating companies, 178 exhibiting companies, 102 media and association partners and offered 44 free workshops. Participants came from 42 countries and 4 continents – Africa, Europe and the Middle East, USA and South America, and Asia and Australasia. 2019 is poised to smash these records. While dmg events’ reach will bring visitors closer to an international audience, the African Construction and Totally Concrete Expos remain South African events, serving to promote local values, business and communities. If there’s one show you can’t afford to miss, this is the one!
Book a stand or register to visit now at www.africanconstructionexpo to be part of the event on 11-13 June 2019 at Gallagher Convention Centre, Johannesburg, South Africa.
Visitors to the 2018 show said The workshops I attended were very useful and I can’t wait to come back next year. Samson Khumalo, Workshop Manager, Coastal Hire We met many suppliers and other companies that we will have synergies with in the future. I will definitely be back next year. Seddick Toffa, CEO, Jojabesi Sourcing We learned how to participate in tenders and how to ensure our company is the government database so that we can grow our business. Raymong Mongale, Director, Djengo Enterprise I came here for the contractors’ section and I found some great products. Next year I have to plan to spend more time at the event. Kay Chetty, Tender Buyer, Temi Construction
February 2019 CONCRETE TRENDS 13
ART & ARCHITECTURE
!Khwa ttu: Celebrating concrete in the natural landscape By Daniel van der Merwe, Architect, PPC
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he world’s only heritage centre dedicated to the San at !Khwa ttu was designed and curated with members of San communities. Concrete was an essential component to allow an architecture of vibrant demonstration of culture and beliefs, as it serves to articulate previously untold indigenous experiences. The centre is located on a former wheat farm some 64.5 kilometres north of Cape Town, near the Atlantic village of Yzerfontein. The region’s history reveals that this was once part of the vast territory of the !Xam Bushmen. In honour of the area’s first inhabitants, the farm name was changed from ‘Grootwater’ (Afrikaans for big water) to ‘!Khwa ttu,’ the term for water or water-pans in the language of the !Xam. !Khwa ttu aims to restitute and display the heritage of the San as contained in their oral history, culture, visual arts, folklore, cosmology, and language. It educates the general public, as well as the uprooted San themselves, about the cultural legacy of the Bushmen. It also provides training and adult education – including skills in tourism, entrepreneurship, and communitybased development – for rotating groups of San. The new centre contains the ‘Way of the San’ exhibition. Designed by architect Geoff George, the ribbed ceiling spaces have been described as a joining of “old wisdom with new technology”. Dug into the side of a bank with a roof covered in grass plantings, it has the feel of an overhang cave. The egg shape of the building is a “symbolic gesture towards the role of the ostrich egg – as an important medicine and a waterhole”. The architectural language was conceived to integrate into the organic landscape with abstracted references to traditional nomadic San structural shelters that were made of lightweight
latte, thatch and skins and with an emphasis on sustainable ecological low impact on the fragile natural environment. This called for an innovative approach through the use of built form, local materials and inventive construction. Concrete was chosen to be one of the principal building materials for its plasticity of form, austerity in aesthetic quality, strength, durability and economy. The roof had to bend in and become part of the landscape. It makes topographical references to the dune landscape of the Kalahari. The living roof adds thermal mass and natural insulation to keep the interior cool during the hot dry summer months. Through extending the natural vegetation onto the roof it further blends in seamlessly with the natural surrounds. To create the undulating composite green roof, weight was of concern. An 80-mm reinforced concrete layer was installed to work in composite action with the curved steel roof beams. I-beams were cut in half and then used as the main structural members. The resulting upside-down T-sections forming the beam soffits are easily bent to the correct varying degree of roof curvatures. The top half of the beams were made up out of a steel plate, held in position by a series of vertical flat sections with gaps in between. This fabricated beam is much lighter than a conventional full-depth beam, which would have been required if the concrete at the top was not used as a compression flange. The concrete has to be a very specific consistency in order to make the various falls of the roof possible. A 42,5 MPa readymix concrete was used, with a slump of 75 as it had to be stiff enough to be hand packed with waterproofing additives added to the mix.
Dug into the side of a bank with a roof covered in grass, the centre has the feel of an overhang cave.
14 CONCRETE TRENDS February 2019
ART & ARCHITECTURE
The concrete roof edge parapets were hand moulded and tied into a retaining wall. Permanent ‘GSB’ shutter boards on 38 x 250 mm SA pine timber rafters were used to span between the individual roof beams to enable the unique curves of the roof and also to act as a ceiling. This dual functionality results in time and material savings on site. The concrete roof edge parapets were hand moulded and shaped to the various curvatures and tied back into a retaining wall. The concrete retaining wall was built as an undulating curve set in between exposed granite boulders as part of the building’s interior. The wall consists of two parts; a reinforced concrete load-bearing retaining wall and a cavity with an internal dry skin of brickwork. This mitigates any possible moisture bridge and seepage into the building. For the floor, a specially pigmented concrete mix was used to emulate the sandy colours of the west coast. A granite stone aggregate from a local quarry was added to the mix and the surface was minimally ground to create a matt and finely textured but uniform surface. The floor was cast and shaped around pre-existing natural site features using flexible formwork and celebrates the rocky outcrops within the exhibition floor surface in a winding fashion. Red Kalahari sand was brought in to cover the surfaces in between which extends the outdoors into the interior with various medicinal plants, animal skulls, and gathering tools. A hydronic underfloor heating system was installed on top of a rigid insulation layer which forms part of an ‘active’ thermal mass design approach for heat radiation during cooler winter months, while the inherent thermal mass of the concrete slab is also utilised as a heat sink. The media centre is shaped as a non-symmetrical eclipse and has a rock store built within the tapering mass of its walls. Air is funnelled through the walls from an underground concrete plenum below the floor level. The wall cavity is divided into different chambers with transverse walls to tie the tapering masonry walls together. The wall ‘chambers’ are hand packed with local granite rocks on top of precast concrete lintels above the underground plenum. Air is drawn up through the gaps between the lintels to cool the rocks at night. During the day air flowing over the rocks can therefore be cooled down before being discharged at the highpoint of the wall into the media centre’s interior.
The concrete walls and floor curve around pre-existing rock outcrops.
These sustainable approaches allow for a climatically stabilised internal environment while also reducing the need for conventional heating and cooling services and their associated energy demands. The building serves as an excellent example of how concrete can play a role in creating a harmonious relationship which is contextual through a combination of passive environmental strategies and contemporary technologies.n Photographs courtesy of Daniel van der Merwe More information from the author, email: Daniel.VanderMerwe@ppc.co.za
February 2019 CONCRETE TRENDS 15
PROJECTS
Battery Park brings skateboarders to V&A Waterfront in Cape Town By Katie de Klee
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Battery Park includes a concrete skatepark, some meandering walkways, in-built benches, a basketball court as well as new pedestrian routes to and from the V&A Waterfront. The park, which is free of charge and reachable via the city’s bus and train network, is designed to attract to all of Cape Town’s inhabitants and visitors, regardless of their economic class and demographic. “The V&A Waterfront is one of the most affluent areas in Cape Town and is frequented by locals and tourists. Battery Park does not simply appeal to a higher demographic but to the greater Cape Town community by providing a safe, public space that offers activities, gardens and a piazza – free of charge and for all to enjoy,” said the team at DHK.
n old coastal fortification in Cape Town has just been transformed into an urban park, skatepark and garden by South African studio DHK. The 12,000-m2 park Battery Park is located in the high-end V&A Waterfront district, which is also home to the Thomas Heatherwick-designed Zeitz MOCAA art museum. It sits on what was once the Amsterdam Battery, a series of coastal fortifications built in the 18th century.
The project forms part of an urban vision developed by the architects DHK to transform the underused Canal District, by bringing a greater variety of visitors. “The intention was to facilitate a new hub of activity within the V&A district whilst being respectful to the heritage of the Amsterdam Battery, once a place of exclusion and incarceration, but now a public space designed to support and engage the greater Cape Town community”, explained lead DHK architect Pierre Swanepoel.
On the elevated park level, visitors can explore landscaped gardens with trees and stone-clad planters while cantilevered steel pergolas scale the design and provide shade. In contrast to the hard landscaping and concrete benches, softer elements like timber have been used for the pergola shading and cladding for parts of the skate park.
The lower piazza level contains 11 boutique shops that line the canal-facing walls and form an active eastern edge to the new canal pedestrian route. The intention behind the piazza was to activate the canal via a range of water sports and provide a link between the V&A Waterfront and the city centre, encouraging a pedestrianised environment.
16 CONCRETE TRENDS February 2019
PROJECTS Much of the park is constructed using concrete, which the architects described as being a material that represents current construction in South Africa and contrasts with the original stonework of the Amsterdam Battery. “At present, concrete is generally used in the construction of multi-storey buildings throughout South Africa,” said DHK. “The intention behind the use of concrete is to ensure a clear distinction between the original Amsterdam Battery and the new additions.”
The old Amsterdam Battery was largely demolished in 1905 to make way for a railway that connected the port to the city. The remnants are now eight metres above the level of the canal that runs through the site. During the construction of Battery Park, the archaeological excavations were used to inform the design. All the stone used
throughout the park and piazza was excavated from the site itself during construction. The raised park sits at the battery’s original inner courtyard level. Planted edges that sit above the retail units on the piazza level estimate the natural ground level that would have fronted the original battery. Various elements reflect the structure’s original footprint, such as semi-circular curved pathways, concrete additions to the rear ramparts, splayed canal-facing walls and concrete-clad structures.
A visual connection to Cape Town’s Noon Gun on Signal Hill has also been retained, preserving the site’s historic sightline. A concealed parking facility is housed within walls made of loosely packed stone-filled gabions, to reference the battery’s original facade.n Source: https://goo.gl/o8Cj52
World’s first underwater hotel opens in the Maldives
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fter years of construction, the world’s first underwater hotel has officially opened in the Maldives. The hotel, which is part of the Conrad Maldives Rangali Island, will allow guests to relax within the waters of the Indian Ocean and is touted by the developers as “an ambitious display of architecture, design, and technology.” Nestled more than 16 feet below sea level, a stay in the Muraka may soon be on the bucket list of adventurous global travellers. The hotel boasts every possible luxury (and a price tag to match). Vistas feature passing marine life rather than just waves or sunsets. The ‘villa’ itself is made up of two levels and includes butler’s quarters, a private bar, and a gym. If the ocean itself is not enough, the space also includes an infinity pool. For all the development’s luxury, the hotel also boasts enviable sustainability credentials. The modular structure was built first in Singapore and then transported to its site in the Maldives. There, each element was nailed to concrete pylons ensuring stability within the shifting tides. “The completion of The Muraka is for me a personal lifetime achievement,” said Ahmed Saleem, the chief architect and designer of the residence, in a statement. “After years in the
making, my team and I are proud to officially present The Muraka residence and its accompanying Maldivian experience to worldly travellers who crave the extraordinary.”n News via CNN Source: https://goo.gl/wLoMz9
February 2019 CONCRETE TRENDS 17
PROJECTS
View of the highwall prior to work commencing.
The 23 metre highwall before it had been cleaned and the CHRYSO TSL liquid polymer (LP) dustless thin-skin liner applied.
The top of the highwall cleaned, meshed and sealed. All cracks have been filled with CHRYSO TSL LP and all loose rock consolidated.
Dustless, thin-skin liner stabilises the Tweefontein highwall
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n order to provide effective stabilisation against geological disturbances, CHRYSO® TSL liquid polymer (LP) dustless, thin-skin liner has been applied over 1,400 m2 of highwall at the Tweefontein coal mine central pit near the town of Ogies in Mpumalanga. The main contractor on the job was the highly experienced Witbank-based mining roof support contractor Martiq whose owner, Japie Kleinhans, has spent over 20 years in this sector. The choice of CHRYSO® TSL LP, which is a two-part product, was to ensure durability by blocking off the rock strata from weathering and oxidation. The two-part CHRYSO TSL system was specially modified and adapted by new business manager, Frans Bakselerowicz and chief chemist, Warren Delaney for the coal mines. Hours of testing and changing mix designs improved the adhesion, biaxial flexural and tensile strengths. The two-part and singlepart TSL are available in natural grey and a brilliant white. In this application, the access from the top of the 23-m highwall made the process easier, as the contractor needed to reach the top of the wall area and five metres over the edge. The gravity feed of the 30-m pipe also facilitated the successful spraying process. Five portal entrances giving access into the mine were also treated with CHRYSO® TSL LP to stabilise the coal substrate. With its extensive expertise in concrete, cement and additives, CHRYSO Southern Africa was able to assist the contractor with consulting services on the project, which was successfully completed in June 2018.
A close-up view of the CHRYSO TSL liquid polymer dustless thin-skin liner coverage at 10 mm over diamond mesh.
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The CHRYSO® TSL LP two-part package comprises fillers, the cement and additives, and polymer. The dry powders are premixed to make the mixing process more convenient. Sprayed onto the required surface at a thickness of between 5 mm and 10 mm, the product’s excellent flowability ensures deeper penetration into crevasses and cracks in the laminated sandstone and shale substrate. It also offers a cost saving and less rebound, as well as quicker application when compared to gunite or shotcrete equivalents. The application is less labour intensive, and it is easy to mix. CHRYSO® TSL LP offers significant health and safety benefits to those working in the environment of the mine or tunnel as it is dustless, non-flammable and non-toxic. Its fast-setting quality gives it early strength gains, whiles its high flexural strength properties provide a flexible barrier. The lining also displays good tensile strength when applied to a large portion of the substrate. In addition to providing soil stabilisation of tunnel works and a reinforcement protection barrier against rock strain movements, CHRYSO® TSL LP can be used as a permanent surface. It can also be used to stabilise areas that are prone to soil movements, as a protection barrier against weathering and soil erosion, and as a liner to prevent rock from oxidising.n
More information from Frans Bakselerowicz, Tel:+27(0)11 395 6700 / Cell:+27(0)62 620 1574 www.za.chryso.com
Spraying of the CHRYSO TSL liquid polymer thin-skin liner completed on top and the vertical face to support faults, slips and all entrance roadways.
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ROADS & BRIDGES
Sustainable monument called for a rugby field of concrete Jan de Beer spoke to the team at GAUFF Engineering in charge of quality control for the construction of the longest suspension bridge in Africa: the amazing Maputo Bridge and North Link Interchange.
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he Maputo Bridge, now the longest suspension bridge in Africa, with 3,300 m of connecting bridge structures, required a very specific and durable building material – concrete that would not only meet the 100-year design life mandated by the Mozambican Government but be visually acceptable and as sustainable as possible. This stipulation led to the substitution of up to 40% of the cement with fly ash, leading to what GAUFF calls “fantastic results and the construction of arguably one of the most durable structures on the African continent.” China Road and Bridge Construction (CRBC) was awarded the Engineering Procurement Construction (EPC) contract for the design and construction of the Maputo Bridge. A requirement that had a drastic effect on the quality of the overall project was the decision to appoint an internal independent quality control consultant. GAUFF Engineering – a German company with head offices in Nuremburg and over 40 years of experience in Africa – was appointed to this position. Furthermore, the decision to utilise fly ash, which is available in abundance from South Africa, and the fact that it was decided to use local cement from Cimentos de Mozambique (CM), made controlling the integral components of the concrete much easier. The now highly-acclaimed Maputo Bridge project is made up of two 140-m-tall reinforced concrete pylons and two 170,000t anchor blocks that support the suspension bridge. Also included are three kilometres of connecting viaducts constructed from precast post-tensioned T-beams in the south and a composite structure in the north consisting of T-beams as well as in-situ cast post-tensioned box girders. These were constructed utilising the balanced cantilever method as construction took place over an extremely active industrial area.
20 CONCRETE TRENDS February 2019
In total, over 340,000 m3 of concrete were cast. To put this into layman’s context, this is equivalent to a rugby field of solid concrete – 50m high. It called for a staggering 850,000 fiftykilogram bags of cement. Both sides of the bay were equipped with computerised 120-m3/hour batch plants, each with individual chiller plants to cope with the high temperatures often experienced in Maputo. Aggregate in the form of Rhyolite and Dolerite was sourced from Namacha about 50 km away – the only area in the whole of southern Mozambique in which suitable aggregate was available. Sand was sourced from the Mohamba River: the river’s coarse-graded sand was compensated for by the very fine fly ash. For the various structures involved in the project, over 300 piles were constructed varying in depth from 110 m for the pylons to an average depth of 50 m for the overall project. This required a very workable self-compacting concrete, so 21 mix designs were done to facilitate the different requirements for individual structures and components. Design strengths varied from 20 MPa to 50 MPa for the pylons, T-beams, box girders, piers, piles, crash barriers, curbing and hydraulic structures Cement (CEM II A-L42.5 N) was supplied by Cimentos de Mozambique (CM). This is a portland limestone cement comprising between 80-94% clinker and between 6-20% limestone with the capacity to produce cement strengths between 42.5 MPa and 62.5 MPa. Two different manufacturers from South Africa were used to supply the project with fly ash to induce pozzolanic activity in the cement. All the fly ash supplied conformed to the requirements of SANS 50450-1:2011 for concrete. The advantage of the addition of fly ash in the range of up to 40% of the total cementitious materials for the fresh concrete was improved workability and lower water requirement for a
ROADS & BRIDGES given slump while slightly retarding the setting time. For the hardened concrete, the main advantages were a significant decrease in CO2e emissions, strength development with age, and lower production costs. Other improvements included the reinforcement’s resistance to chloride attack, improved sulphate resistance, refinement of pore structure, reduction of permeability, prevention and retardation of the alkali-silica reaction, reduction of heat generation caused by hydration and a reduction in the risk of thermal cracking that could possibly have taken place during the casting of the three anchorage bases. Internal cooling systems utilising pumped cooled water were extensively used throughout the project. Two of the unique aspects of the concrete on this project were the addition of up to 40% fly ash or pulverised fuel ash (PFA) and a specially formulated polycarboxylate superplasticiser supplied by Chinese company, Sobute New Materials Co. Ltd. This not only offered immediate cost savings (7%) but also long-term benefits. The PFA, sourced from South Africa, enabled the concrete to achieve much higher long-term strength gains, and the fineness of the PFA contributed to the concrete being less permeable, producing a very durable concrete, since the river sand – as previously stated – lacked fines. An additional benefit of the PFA was an estimated 20% reduction in heat produced. The water-reducing superplasticiser used was particularly important because of the casting to extreme depths and heights which necessitated a highly workable (200-230 mm slump) concrete with good flow characteristics and delayed setting time. The water reduction and ion exchange effect of the superplasticiser, combined with the fly ash, greatly contributed to the durability and strength of the concrete – confirmed by the University of Cape Town’s Concrete Materials & Structural Integrity Unit which tested samples cored from the bottom slab of the anchorage six months after casting. The UCT report stated that the result of the cores tested was the best yet obtained from site-manufactured concrete tested at its facility up to 2016. Although the durability indexes did not form part of the employers’ requirements and the added cost was borne by the contractor, it was bilaterally decided to do index testing on concrete at varying ages to confirm that substituting cement with fly ash did indeed improve not only the strength with age factor, but also played a major contribution in increasing the durability of the structure to guard against the harsh marine environment. For this project, GAUFF and CRBC together with the client developed a comprehensive quality management monitoring system, which covered all aspects of construction in Maputo and also the extensive production of the complex steel components that were manufactured in China. The project’s massive workforce (peaking at 2,370) included Mozambicans and Chinese staff, with the quality control engineering and supervision staff totalling 36. In total, 14,526, 940 man-hours were recorded on the project until the end of October 2018 with thousands of households benefitting financially through employment and skills transfer – factors that will have a lasting effect on the local community. More than 600 families were relocated out of poor environmental conditions and given title deeds to their own serviced plots and financially rewarded, enabling them to construct personal homes. In response to worldwide interest in this project – and its exceptional concrete characteristic and properties – technical papers have been presented at several high-ranking conferences in many countries with the interest mainly generated by the extensive use of fly ash and exceptional durability test
Maputo Bridge mid span view.
The North view of the bridge.
The North Link interchange. results obtained from the concrete cover layer of different construction elements. The University of Johannesburg’s Facility of Engineering & Built Environment also visited the bridge and GAUFF Engineering has provided input at conferences and to various international publications. Mozambicans can truly be proud of a masterpiece of infrastructure engineering that will dominate the skyline of Maputo forever and be a global construction landmark and achievement for the entire southern part of the African continent.n Input provided by GAUFF Engineering’s Lawrence Greene, section head; and Dean Swanepoel, quality manager & senior materials engineer for the Maputo Bridge and Link Roads Project. Visit www.gauff.net
February 2019 CONCRETE TRENDS 21
ROADS & BRIDGES
Eastern Cape road project boosts safety and targeted enterprises
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afety of both the pedestrians and motorists has been boosted by Concor Infrastructure’s rehabilitation of the R75 double carriageway between Port Elizabeth and Uitenhage, while the project has also had considerable positive spinoff for local small targeted enterprises. The project, which commenced in May 2017, includes the implementation of various road safety measures on Section 1 – a 13-km stretch – of this well-used national route. According to South African National Roads Agency SOC Limited (SANRAL), between 6,100 and 7,100 vehicles travel northbound on this route each day, including about 500 trucks. At the same time, over 4,500 pedestrians use the road, almost half those being children. Previously, the road had some of the highest pedestri- A grader processing sidewalk fill next to the kerb line on the R75 road contract an accident numbers in the Eastern Cape. Concor Infrastructure’s site agent, Roy between Port Elizabeth and Uitenhage. van Leeve, says there will be some 70 to 80 small targeted enterprises working on the contract over its duration. Among the subcontracting opportunities arising from the project have been relocating and installing traffic signals, accommodating traffic, constructing lane widenings, installing sub-soil drains, guardrails, gabions, precast retaining walls and anti-climb fencing. “The targeted enterprises have also been engaged to provide the concrete linings for open drains in the road median, and for the concrete palisades, concrete-surfaced sidewalks, road markings as well as road studs,” Van Leeve says. He highlights the many support measures that Concor Infrastructure has put in Preparation for concrete lined drained place to transfer skills to the targeted en- on Concor Infrastructure’s road contract terprises. These assist the small contractors between Port Elizabeth and Uitenhage in building their capacity to enable them on the R75. to become sustainable businesses. “Our engineers on site have each been allocated a number of targeted enterprises to supervise and mentor,” he says. “Many of the newer subcontractors have not had to operate on our level of professionalism before, so they will undergo a considerable learning curve when dealing with quality systems, or health and safety. We work with them to put various systems in place in their own businesses, so that they are able to operate more independently when they move off site.” Each of the small targeted enterprises receives hazard identification and risk assessment (HIRA) training, as well as training on construction regulations and legal Concrete sidewalks being installed by liability which they can apply to their own subcontractors on Concor Infrastructure’s business operations. The mentoring role R75 roads contract.
22 CONCRETE TRENDS February 2019
includes training the targeted enterprises in planning of activities, in generating daily costings and procuring their materials. Another important aspect of each targeted enterprise’s development is for us to ensure that they invariably leave the contract with a higher Construction Industry Development Board (CIDB) grading than they were on at the time they started work on the project. “If a sub-contractor with a Level 2 CIDB grading gets work with us, the contract is set up so that they will progress to a Level 3 grading by the time they complete their work here,” he says. “This is all part of the major developmental agenda that is in place on this project.” Another important aspect of the work that will benefit these enterprises is the street lighting component, which is rolling out new street lights along the full length of the rehabilitated roadway. This involves the installation of about 25 km of electrical cabling, which will be encased in concrete. “This activity has been set aside for women labour, including the complete trench excavations as well as the encasement and backfilling,” Van Leeve says. Thirty percent of the value of sub-contracted work is being directed to targeted enterprises, he says, with about a third of that going to women-owned businesses and a similar portion is being allocated to youth-owned businesses. As part of the local empowerment focus of the project, labour was recruited from the nearby residential wards to ensure that employment and skills training benefits were shared with local communities. The current phase of the contract is due for completion in 2019.
Key project facts By completion, Concor Infrastructure’s rehabilitation on this section of the R75 will have involved 15,000 m3 of fill, from both commercial sources and from bulk excavations on site. A cement-stabilised sub-base layer – amounting to 56,000 m3 in volume – was applied to sections of the road, consuming 2,600 tonnes of AfriSam Roadstab. For the surfacing, about 93,000 tonnes of asphalt is being supplied by a Port Elizabeth-based supplier. Some 16,000 m3 of concrete will be used by the end of the project, for installations including 17 linear kilometres of concrete sidewalks and 7 km of concretelined drains in the median. The project also
ROADS & BRIDGES involves 4,4 km of subsoil drains and 4,4 km of concrete-lined side drains. As an important part of the safety-enhancing features of the work, there will be 45 km of guardrails and 18 km of anticlimb fencing along the route. Concor Infrastructure’s commitment to safety is reflected by the achievement of 550,000 Lost Time Injury Free (LTIF) hours by the end of September 2018. High-quality work is ensured by close monitoring and supervision, carried out through daily inspections and weekly audits. This has led to consistent client audit results on site of between 96 and 98%. Ongoing skills development includes the opportunity for 10 civil engineering students to gain work experience on site, benefiting from the mentorship of Concor Infrastructure engineers while undergoing experiential learning in fields such as construction management and survey.n More information from Concor Infrastructure, Tel: +27(0)11 590 5500 email: info.infrastructure@concor.co.za www.concor.co.za
Preparation of sidewalk fill and widening of cuts on Concor Infrastructure's contract on the R75.
World’s longest bridge in Kuwait to be completed soon
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he world’s longest bridge, Sheikh Jaber Al-Ahmad Al-Sabah Causeway Project (Main Link), linking Kuwait City to Subiyah New Town across Kuwait Bay is set for completion in 2019, reported South Korean media. Korean company, Hyundai Engineering and Construction (Hyundai E&C) will complete the bridge, six years after winning the $2.6-billion project in November 2013, along with local company Combined Group. Hyundai E&C’s share of the project is 78% of the total construction cost. Reports also stated that this is the largest civil engineering project landed by a Korean contractor since the waterway order from Libya in 1984. The total length of the bridge is 48.53 km, including the 36.1-km-long main bridge and the 12.43-km-long Doha Link, which is also another project under construction by Hyundai E&C in Kuwait. Sheikh Jaber Causeway will be about 7 km longer than Haiyan Bridge (41.58 km) in Qingdao, China. Business Korea also reported that the core of the project is the construction of the main bridge. The central part of the marine bridge, a 340-m section, is built in the form of an asymmetric cable-stayed bridge, which requires ‘high-level design and construction technology’. Recently, Kuwait’s state news agency also reported that Kuwait’s Public Roads and Transportation has announced the in-
The Sheikh Jaber Al-Ahmad Al-Sabah Causeway is estimated to cost US$3 billion.
auguration of a 4.7-km ‘land-section’ within the Sheikh Jaber Al-Ahmad Al-Sabah Causeway Project which is part of the link within the causeway that starts at Al-Ghazali Bridge.n Source: https://goo.gl/xvBCdX
The project includes the construction of two artificial islands.
The central part of the marine bridge is asymmetric and cable-stayed.
February 2019 CONCRETE TRENDS 23
ROADS & BRIDGES
World’s largest 3D-printed concrete pedestrian bridge completed in China By Niall Patrick Walsh
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he longest 3D-printed concrete pedestrian bridge in the world has recently been completed in Shanghai. Designed by Professor Xu Weiguo from the Tsinghua University (School of Architecture) – Zoina Land Joint Research Center for Digital Architecture, the 26.3-m-long bridge was inspired by the ancient Anji Bridge in Zhaoxian, China. The single-arch structure was created using a 3D printing concrete system developed by Professor Xu Weiguo’s team, integrating digital design, cost efficiency, smart technology, and architectural dynamism. Enclosing the 3.6-m width, the bridge’s handrails are shaped like flowing ribbons on the arch, creating a light, elegant movement across the Shanghai Wisdom Bay pond. The bridge structure is constructed of 44 hollowed-out 3D-printed concrete units, while the handrails are divided into 68 units. The bridge’s components have been printed from composite materials, containing polyethylene fibre concrete to match the structural performance of conventional materials. The design process involved the construction of a 1:4 scale physical model of the bridge, built to demonstrate the scheme’s viability, and proving that the bridge could hold pedestrians crowding the entire surface. For the actual construction, concrete components for the bridge were printed by two robotic arms, over the course of
450 hours. The streamlined process is estimated to have produced savings of 33% when compared to a more conventional construction process – attributed mainly to the elimination of templates and reinforcing bars. Embedded in the bridge, a real-time monitoring system provides data on vibrating wire stresses and strains. The results will allow for a greater understanding of the practical performance of new concrete materials, and the structural properties of 3Dprinted components. The bridge was jointly built with the Shanghai Wisdom Bay Investment Management Company. Concrete is not the only material undergoing major change as a result of 3D printing technology. Earlier this year, Columbia University unveiled a new technique for 3D printing and scanning, producing a timber lookalike with an authentic interior grain. Meanwhile, the world’s first 3D-printed steel bridge was recently unveiled at Dutch Design Week. Architects: Tsinghua University (School of Architecture) Zoina Land Joint Research Center for Digital Architecture; Design Team: Weiguo Xu, Chenwei Sun, Zhi Wang, Yuan Gao, Zhiling Zhang, Changzhuan Shaon All photographs by Professor Xu Weiguo Source: https://goo.gl/VW6LiQ
24 CONCRETE TRENDS February 2019
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REINFORCING MATERIALS
Memory steel: a new material for strengthening buildings By Swiss Federal Laboratories for Materials Science and Technology
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new building material called memory steel, developed at the Swiss Federal Laboratories for Materials Science and Technology (Empa), is about to be launched on the market. The material can be used to reinforce new and existing concrete structures. When the material is heated, prestressing occurs automatically. Today, steel reinforcement in concrete structures is mostly prestressed hydraulically. This requires ducts for guiding the tensioning cables, anchors for force transfer and oil-filled hydraulic jacks. The space requirement of all this apparatus creates the geometric framework conditions for every prestressed concrete structure. Thus the strengthening of older structures sometimes fails due to the high space requirements of this established method. After 15 years of research, experts from Empa now report an alternative method to series production readiness: shape memory alloys based on iron that contract during heating and thus permanently prestress the concrete structure. Hydraulic prestressing can thus be avoided – it is sufficient to heat the steel briefly, for example, by means of electric current or infrared radiators. The new building material will be marketed under the name Memory Steel. Several pilot projects, such as the reinforcement of various reinforced concrete slabs, have already been successful.
Development of memory steel The development of memory steel began in the early 2000s. In previous decades, Empa had already pioneered the strengthening of concrete with carbon fibre reinforced polymers (CFRP). This led to the idea of using shape memory alloys for prestressing concrete. Initial tests with nickel-titanium alloys were positive, but the material, already known from medical applications, was far too expensive for use in the construction sector. In 2009, Empa researchers succeeded in developing an ironbased shape memory alloy, which they also patented. In 2012, researchers around Julien Michels finally founded the company Re-fer AG; Michels has been CEO of the company ever since. Memory steel is intended to be used for the strengthening of existing buildings. For example, as soon as new windows, doors or lift shafts are installed in the concrete structure of an old building, a new reinforcement of the load-bearing structure is often unavoidable. In industrial buildings, the load-bearing capacity of an old suspended slab sometimes has to be substantially increased. Thanks to memory steel, such tasks can now also be successfully undertaken in confined spaces. A strip of special steel can be fastened under the ceiling using dowels and then heated with electricity or an infrared radiator. Alternatively, the reinforcement can also be set in concrete. First, a groove is milled into the surface of the concrete slab; then a ribbed reinforcement bar made of memory steel is inserted into the groove and filled with special mortar. Finally, the profile is heated with the aid of direct current and thus prestressed. Another variant is to embed the reinforcement bar in an additional shotcrete layer. Precast concrete elements with special geometry In future, memory steel could also be a successful method for manufacturing precast concrete parts with a previously unknown geometry. The hydraulic prestressing used to date creates friction in curved structures, which greatly limits the use of this method. With a memory steel profile embedded in concrete, highly curved elements are now also possible. When heated, the profile contracts uniformly over its entire length without friction losses and transfers the stress to the concrete.n Source: https://goo.gl/1pEbne
Further reading Shape-memory alloys for the building industry: https://goo.gl/GzadrP. Moslem Shahverdi et al, Iron-based shape memory alloy strips for strengthening RC members: Material behaviour and characterization, Construction and Building Materials (2018). DOI: 10.1016/j.conbuildmat.2018.04.057 Reinforcement of an intermediate slab with memory steel. Credit: Swiss Federal Laboratories for Materials Science and Technology
26 CONCRETE TRENDS February 2019
11 - 13 June 2019
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READYMIX
Advanced technology is serving to grow readymix markets
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Specific challenges faced have been the rising cost and variable quality of aggregate and sand.
CHRYSO Quad and Optima technologies provide solutions that are most important to customers – concrete strength, slump or open time.
Readymix suppliers look to admixtures and technology for growth.
28 CONCRETE TRENDS February 2019
y leveraging its admixture technologies and its growing range of value-added products, CHRYSO Southern Africa is helping its readymix customers expand their markets despite the flat conditions in the construction sector. According to Deon Klopper, sales manager readymix segment at CHRYSO Southern Africa, the slow economy continues to pressure readymix suppliers, but the answer lies in offering end users more options to reduce their costs while continuing to deliver quality results. “This is where the role of CHRYSO’s research and development efforts – leading to ongoing technology advances – is becoming so important to the readymix sector,” says Klopper. “Working closely with both the readymix supplier and the end user, we ensure that we understand what both parties require.” This enables CHRYSO to share information with end users about the range of cost-effective options, which they then purchase through the readymix supplier. “All end users need to produce their concrete at a certain optimum cost per cubic metre to remain competitive, while still retaining the required quality,” he says. “At the same time, the readymix producers can use our value-added products to help grow their markets by offering more solutions to the end user.” CHRYSO Southern Africa has continued to expand its range to include technologies such as fibres, mould release oils, curing compounds, decorative concrete, permeability reduced watertight concrete and dust suppressants. “While the readymix supplier was, in the past, expected just to deliver what the customer ordered, they can now offer their customers more by servicing other site requirements and make useful cost-saving proposals,” he says. Among CHRYSO’s admixture developments, for instance, is CHRYSO® QUAD 20, which allows end users to utilise lowergrade sand, where sand and aggregate quality has become more variable. CHRYSO® Quad 20 is a unique formulation which increases the viscosity of cement paste with limited impact on concrete slump and slump flow. Klopper also highlights CHRYSO’s focus on providing fit-for-purpose solutions that are suited to the specific priorities of any given project. “We ask all our customers what is most important in each of their projects – such as the concrete’s strength, slump or open time – and we can then manufacture an admixture specifically for their readymix concrete,” he says. “Our CHRYSO® Optima 1000 technology, for instance, represents a formula that adjusts to match every customer’s demands, with unprecedented flexibility producing maximum robustness, reliability and precision. It offers up to seven-hour workability retention and up to 50% water reduction for an optimal dosage per cubic metre.”n More information from Elrene Smuts, Tel: +27(0)11 395 9700 email: elrene@chrysosa-abe.co.za www.za.chryso.com
Caleon and AfriSam show learners the art of concrete
For Caleon Garden Creations, this initiative is one in which all employees proudly contribute, as they take the learners under their wing to make it a success.
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ore learners at The Gateway School, a leading school in Roodepoort for special education needs, were recently empowered in the art of concrete creations. Through a structured mentorship programme undertaken by precast concrete manufacturer Caleon Garden Creations, learners are being given the opportunity to create their own art using concrete. A range of other skills is also being imparted during the initiative, creating concrete possibilities for learners as they prepare to graduate. The Gateway School’s focus is helping learners with special needs to achieve their full potential, by providing excellent educational opportunities and developing each learner holistically. This includes empowering them with the skills and knowledge they need in the world of work. In doing this, the school often partners with corporates to expose the learners to various skills and has partnered with Caleon Garden Creations for the last four years. AfriSam recently came on board to support Caleon Garden Creations in this worthy cause. In the programme, three or four learners are taken in at a time, and management and employees take these youngsters under their wing. With a factory in Rietfontein, Caleon Garden Creations manufactures a wide range of concrete products such as tables, benches, pots and water features. For AfriSam, with its commitment to community upliftment and empowerment, this initiative represented a fitting cause. The company’s own efforts are focused on initiatives that are sustainable and enable the beneficiaries to be self-sufficient. “We are very excited to be a part of this initiative and are inspired to see the work that Caleon Garden Creations has been doing with The Gateway School.� said Adele Wentzel, sales manager for AfriSam. At the completion of their practical block, learners were excited to show off their creations and exuded confidence in working with concrete. It was a proud moment for all involved as they witnessed the achievements of these learners and their enthusiasm in showcasing their art. Caleon Garden Creations owner Ferdi de Wit said: “For my team and I, working with The Gateway School is a heart-warming tradition that we are proud to carry through. It is our greatest pleasure to impart skills that these young learners can use. Hopefully, we have inspired them to build on these skills and to create their own businesses in the future. With each group that joins us, we are always inspired by the commitment from the school.� The Gateway School’s occupational therapist Karen Botha said: “Our continued partnership with Caleon Garden Creations and now with AfriSam gives our learners opportunities to learn new skills, helps them build confidence in their abilities and shows them just how much more they are capable of.�n
More information from Maxine Nel, Tel: +27(0)11Â 670 5893 email: maxine.nel@za.afrisam.com / www.afrisam.com
February 2019 CONCRETE TRENDS 29
PRECAST CONCRETE - CSI
Find your nearest supplier www.terraforce.com
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PRECAST CONCRETE
Specialist geotechnical engineering required for 12-m-high Bakoven wall
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imited space and precipitous slopes called for specialist geotechnical engineering in constructing some of the concrete block wall structures in Bakoven on Cape Town’s Atlantic seaboard which were installed by Terraforce Recommended Installer, Dassenberg Retaining Systems.
Pedestrian bridge connecting the building to the 4×4 Step block stairs running along both sides of the property.
Specialist geotechnical engineering was required in constructing Terraforce walls in Bakoven, Cape Town. The walls were built to retain a steep granite embankment which was cut to create a building platform for construction of Infinity, a luxury six-storey apartment block offering spectacular views of the Atlantic and the Twelve Apostles mountain range.
Apart from the sea-facing front elevation, the remainder of the building is enveloped in a cocoon-like concrete block wall structure of varying heights and angles.
Limited space and precipitous slopes called for specialist geotechnical engineering for some of the Terraforce concrete block wall structures. Apart from the sea-facing front elevation, the remainder of the building is enveloped in a cocoon-like concrete block wall structure of varying heights and angles. The walls were designed by structural engineer, Fred Laker, with geotechnical engineering input on the three walls at the rear of the property from Kantey & Templer Consulting Engineers for the principal retaining components. All the walls were built by Dassenberg Retaining using L12 retaining wall blocks supplied by CMA member, Cape Retaining Systems. Geotechnical site inspections and a detailed slope stability analysis conducted by Kantey & Templer revealed that most of the materials exposed in the cut face were deeply weathered granites. It was determined that, if left unsupported, parts of the embankment could be prone to instability during periods of high rainfall.
30 CONCRETE TRENDS February 2019
After assessing the various support options available, Kantey & Templer recommended that two of the three main rear concrete block walls should be provided with 300-kN tie-back anchorages and concrete waler beams. Geofabric reinforcement was not an option due to the space between the retaining wall block facing and the embankment face being only 300 mm. Steel reinforced, the waler beams measured 350 mm thick and about 1000 mm high. They were constructed on the upper and lower wall sections and span the full width of the embankment face.
Fire escape staircases on each side of the property were built as part of the retaining wall structures using Terraforce’s 4×4 Step blocks.
PRECAST CONCRETE Further reinforcement was achieved by filling the block-work in the lower half of each of the three main concrete block walls with steel reinforced concrete. Free-draining sand was also used to fill the space between the blocks and the embankment. The total combined height of the backyard walls is 12.4 m. The lower wall is the highest at 5.6 m. The middle wall tops 3.7 m and the upper wall 3.1 m. Each wall was built at an angle of 75˚. There are two narrow terraces between the lower and middle walls and the middle and upper walls. A sophisticated sub-surface drainage system was built into the design to handle the percolation of water from the slope and to prevent the build-up of pore pressure. In addition, rain water flowing off the mountain slope is captured in a stone filled trapezoidal concrete channel which drains away from the wall into the storm-water drainage system. Perforated 100-mm pipes were installed at the View down the steps. bottom of the fill material behind each wall. These fine grading, installing drip line irrigation, planting indigenous, drain into core drain pipes which drain into stormwater-wise plants, laying stone, installing the modular planter water pipes. The storm-water pipes run under the building and system and some rehabilitation work. Besides planting the terdrain into a silt trap which flows into municipal drainage. races and down the sides of building alongside the retaining Fire escape staircases on each side of the property were built walls, each level of the building had planting on the balconies as part of the retaining wall structures using Terraforce’s 4×4 installed using a modular system in which plants were planted Step blocks. up in crates instead of in actual planters. This enables easy reLandscaping on the terraces and walls was undertaken by moval of sections to replace plants when necessary.n Urban Landscape Solutions, who were responsible for the
Perfect pedestrian ramp, Silicon Oasis, Dubai!
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etaining walls can do so much more than just stop soil erosion and flooding issues. Along with other hardscaping and landscaping, retaining walls can transform grounds by providing depth and verticality to the landscape, creating raised platforms for gardens, terraced views of the property, and beautiful concrete block textures. This building site, located at DSO (Dubai Silicon Oasis), Lake Park, needed a pedestrian ramp and vertical boundary wall to connect an upper parking level with a new community park venue, lower down. The resulting cut and fill slopes where retained using Terraforce L16 blocks, manufactured locally by Consent LLC. The blocks were specified by main contractor, Proscape, who had used the product at DSO previously. Says Awad, Al Aamal Construction, who installed the blocks: “We used precast foundations, 600 mm wide and 150 mm deep. For the vertical walls we placed steel rebar every 900 mm and filled the blocks with concrete, as well as installing horizontal steel bars – by cutting grooves into the blocks – in the second-last row for extra stability. “The other walls were placed on a similar foundation, with geogrid every second layer and the first four block rows were concrete filled. Work was completed January 2018 and in total 5,000 L16 Terraforce blocks were used.”n
Cut and fill slopes where retained using Terraforce L16 blocks, manufactured in the UAE by Consent LLC with the pedestrian ramp down to the play area.
Architect: Khatib and Alami Main Contractor: Proscape Sub-contractor: Al Aamal Construction LLC More information from Terraforce, Tel: +27(0)21 465 1907 / www.terraforce.com
The completed walls with gorgeous curves, textures and fencing.
February 2019 CONCRETE TRENDS 31
PRECAST CONCRETE
New precast concrete wall system accelerates water delivery in Mpumalanga
Corestruc is able to construct the walls and roof in as little as three months on site, while the manufacture of the structure takes place at the factory during the earthworks and construction of the foundations.
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new precast concrete reservoir wall system has been successfully deployed on two water schemes that will significantly strengthen drinking water supply to areas of Mpumalanga. Both project sites provided an ideal opportunity to refine the system ahead of its commercial launch by Corestruc, a leading South African precast concrete specialist. The first 10 Ml command reservoir was built by Corestruc in KwaMhlanga and the second such structure in Bundu. In both instances, the new precast concrete wall technology was used in combination with the company’s tried-and-tested modular roof structure. Notably, this is the first time that a South African municipality has used Corestruc’s precast concrete wall system, based on what is considered to be international best practice and adapted to unique local conditions. Monde Consulting Engineers and Ceenex motivated the use of the new technology to representatives of Thembisile Hani Local Municipality to significantly accelerate the construction of the two structures as vital components of the water schemes. Using the system, a reservoir wall for a structure of this size can be built in as little as five to six weeks, while also providing significant cost-savings in the construction of larger reservoirs. Meanwhile, Corestruc is contractually liable for the performance of all its systems, which helped allay any initial concerns regarding the use of the new technology on these important projects. The walls of both structures comprise 60 precast concrete panels, each weighing eight tons, and are 9,8 m in length and 16,4 m in width. Manufactured at Corestruc’s factory, they are transported to site and then placed on top of the ring-beam that is built by the main contractor once the centre portion of the structure, comprising precast concrete columns, beams and hollow-core slabs, has been completed. The precast concrete wall panels, as well as the four buttress panels were manufactured using specialised forms that were designed and produced by CoreEngineering. As essential components of Corestruc’s post-tensioning system that assist in reinforcing the walls both vertically and horizontally, the buttress panels contain many cast-in com-
32 CONCRETE TRENDS February 2019
ponents that were all manufactured by the company’s own engineering department. CoreEngineering also designed the three-dimensional prints that are used to secure the rubber cast that serves as a temporary shutter for the grout. Ceenex and Monde Consulting Engineers worked closely with Corestruc to refine the system for these two projects. Special attention was also given to the grouting process, the most time-consuming and intensive process of the entire construction phase. At both structures, about 6,6 km of post-tensioning ducts and cables were installed by hand between the joints of the wall panels, before the grout could be pumped around the circumference of the reservoir. The grout has been designed to reach a compressive strength of 100 MPa within four days and to further react when the medium comes into contact with water when the reservoir is being filled. Designed by Corestruc, it is blended and packaged by Epoxerite, a leading South African construction chemicals specialist. As part of the service offering, the company also undertakes regular testing of the material to ensure a consistent high quality of supply. The grout underwent extensive testing ahead of its application, and Corestruc even brought its own water to the first construction site in KwaMhlangu to ensure it achieved the desired reaction. Importantly, the grout has to be very flowable to be pumped through all of the post-tensioning ducts from a single position using two pumps in a process that takes up to two days to complete. It is pumped in a controlled manner and the working time of the grout is extended by cooling it down to seven degrees Celsius. Willie de Jager, managing director of Corestruc, concludes that he is proud to be associated with Ceenex and Monde Consulting Engineers, both respected participants in water infrastructure, and lauds Thembisile Hani Local Municipality for its visionary approach to service delivery.n More information from Corestruc, Tel: +27(0)87 232 2462 / www.corestruc.co.za
PRECAST CONCRETE
New healthcare clinic chooses JZZ pavers
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ealth care clinics by their very nature have an enormous amount of foot traffic that requires safe, sturdy, attractive and long-lasting paving. The new Jouberton Community Clinic, a primary health care centre in Klerksdorp, North West Province, sought paving that offered these features and was cost effective. Technicrete, part of ISG, fitted the bill, and their JZZ pavers were installed throughout the clinic surrounds. “The quality of our JZZ pavers was the main reason our Technicrete product was selected,” said sales consultant for Technicrete, Wian Blom. “We had recently utilised the JZZ paver at a project in Mafikeng, and when we showed the contractor, Trade First, the finish on the pavers they were happy with the quality and contracted us to install these at the Jouberton Community Clinic.” Technicrete installed 7,500 m2 of JZZ 80-mm pavers as well as 2,500 m2 of 60-mm pavers – all in a slate colour. These were installed alongside the community clinic’s new driveways. “We were then asked to install JZZ pavers to the adjoining road that services the community clinic. This is a project where a substantial quantity of our pavers was required, and our nearby manufacturing factory in Stilfontein was able to ensure that the necessary quantities were delivered as and when required by the project contractors,” Blom said.
Paving the clinic’s adjoining road required large quantities of JZZ pavers. The Technicrete JZZ paver is a solid block interlocking paver that, once applied, forms a continuous, hard-wearing surface. They are suitable for municipal parking areas, domestic driveways, petrol forecourts, pedestrian pavements, pathways and commercial developments and industrial and factory roads. Any area that needs to accommodate regular foot and vehicle traffic, including delivery bays where forklift trucks are utilised, will find the JZZ paver a most practical and suitable surface. Technicrete is part of ISG which also includes Rocla.n
New Wesbank premises feature Cottage Stone pavers
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n the N12 Treasure Route, 185 km south of Johannesburg, you will arrive in Klerksdorp and find new shopping centres, health care clinics, banks and a burgeoning motor vehicle industry that have been developed to meet the expanding community and business requirements of the area. Technicrete was contracted to supply paving for these new developments. With many motor traders moving closer to the N12 for its excellent exposure, Wesbank has recently taken occupation of new offices in this up-and-coming part of Klerksdorp where the new Matlosana Mall is situated. Technicrete sales consultant, Wian Blom said: “The excellent finish on our newly launched Cottage Stone pavers coupled with the fact that they are manufactured only 10 km away from Wesbank’s new building enabled Technicrete to easily supply stock to this new commercial development”. “Our Double Zig Zag (DZZ) pavers along with the Cottage Stone pavers were installed around the main building. As two stands were separated along the side of the project stand, a height difference became evident and our Enviro-Wall retaining wall system was applied”. Technicrete’s DZZs are interlocking pavers that offer a hardwearing surface that is suited to high foot-traffic environments. The pavers form a continuous surface overlay. Aesthetically elegant, they offer an economical and appealing finish. “Aggeneys, a small mining town in the northern Cape installed Technicrete DZZ pavers 40 years ago, and they are still going strong,” said Blom. The Enviro-Wall is a cost-effective yet simple gravity retaining wall system. Its easy construction from dry stacked interlocking,
Cottage stone pavers are suited to high-volume areas. precast blocks allows the blocks to be easily and quickly laid to form an effective retaining wall system. The system is particularly suited for earth embankments, and landscaping of cut and fill areas around buildings. Technicrete’s new Cottage Stone pavers are durable enough for high-volume areas such as municipal parking areas, pedestrian walkways, domestic driveways, general pathways and commercial developments. They are available in the following colours: plum, slate, terracotta, tan, grey and autumn. Technicrete is part of the ISG which also includes Rocla.n More information from Malebusa Sebatane, Tel: +27(0)11 670 7600 email: Malebusa.Sebatane@isgroup.co.za www.technicrete.co.za
February 2019 CONCRETE TRENDS 33
PRECAST CONCRETE
The benefits of a battery mould in production of precast solid walls and floor slabs
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he manufacture of solid walls and solid floors can benefit from battery moulds which greatly assist in increasing the production of these products despite restricted space in the precast plant. They also ensure that a smooth and readyto-paint finish is achieved on both sides of the panel. Solid walls are similar to solid floors, in that they are constructed from concrete and can be manufactured in any structurally required thicknesses. The solid wall is cast at the factory and then delivered, completely ready for installation, to site. Solid walls are used as façades or as functional walls. They are well suited for structural load-bearing applications. The Elematic battery mould offers high production capacity in a very compact format with all handling done in a vertical position. The battery mould is fast to install and movable. Available in both one- and two-sided versions, the two-sided version offers the flexibility of both sides being able to be used independently. Elematic’s battery mould is easily customised: the number and size of its casting cells as well as the mould furnishing can be chosen to meet the individual needs of the factory. It is also possible to add more casting cells to an existing mould if needed, or to upgrade a traditional mould into a cold shuttering version. “If only a small amount of floor space is available at your precast plant, this space can be utilised to the maximum with a
A solid wall panel cast with a door opening using a battery mould.
34 CONCRETE TRENDS February 2019
Elematic’s battery mould is easily customisable and the cold shuttering system enables doubling output and increasing the casting sequence. battery mould – as the casting happens vertically. The most common wall panel size produced is 3 x 8 m, and such a panel can be cast in every casting cell. All the furnishing – e.g. door and window openings and electrical wall sockets – also happens vertically,” said Elematic’s product director, Wall Technologies, Toni Koitmaa. “The Elematic battery mould is easily customised, and with a cold shuttering version, you can double the output and increase the casting sequence,” said Koitmaa. “Normally, it takes 8 – 10 hours for a slab cast in a battery mould to cure, but the cold shuttering version is available for a new casting round after a four-hour pre-curing process,” Koitmaa added. “Because the mould is equipped with plates that divide the casting cell of a traditional battery mould into two separate cells, it enables production of two products instead of the usual one”. Elematic’s cold shuttering system also doubles the capacity of a traditional battery mould. The system speeds up the production cycle and allows two castings per day. In a cold shuttering system a casting cell of a traditional battery mould is divided into two separate cells with a partition plate. The partition plate – a shutter plate – moves most of the process steps outside of the actual battery mould, significantly speeding up the production. Furnishing of the 20-mm-thick cold shutter plates happens outside the mould. After casting and pre-curing, the slabs attached to the cold shutter plates are moved to special rack holders for final curing and de-moulding. Immediately after the mould is empty and clean, another casting round can be started by placing new already furnished cold shutter plates to the casting cells. The entire process saves time while increasing slab production. Elematic Oyj is a world-leading manufacturer of precast concrete plants and production lines. In our more than 50 years of operation, we have supplied technology to over 100 countries and to every continent. Elematic has subsidiaries and sales offices in the USA, Germany, China, Russia, India, Hong Kong and the United Arab Emirates, and agents in over 20 countries.n More information from Nina Lehtonen, email:nina.lehtonen@elematic.com / www.elematic.com
Western Cape improves ease of doing construction business
Concrete Testing Equipment
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he Western Cape is taking great strides to improve the ease of doing construction business in the province. Currently it takes approximately 88 days to obtain a construction permit in Cape Town, a timeframe that is faster than in most high-income countries. Not only does Cape Town remain one of South Africa’s foremost economic hubs, but, according to Cape Town’s Central City Improvement District, with so many construction projects due to break ground by 2020, the overall valuation of local property is set to double over the next 5 to 10 years. The Western Cape currently contributes 13% to South Africa’s annual GDP.
“The event was a great success for us in finding new clients. It was also a brilliant opportunity to meet with existing clients who gave us positive feedback on how we have delivered on the promise of quality of our products. Paul Smith, Managing Director, Sanika Waterproofing.” Platforms such as the Cape Construction Expo provide expanded opportunities to access this market by enabling professionals to engage in facilitated public and private sector collaboration and a multi-lateral approach to local project delivery. The Cape Construction Expo, the only event dedicated exclusively to the building and construction industry in the Western Cape, returns to Sun Exhibits at the GrandWest from 11 to 12 September 2019. This initiative, attended by over 3,700 construction professionals every year, presents a unique opportunity for product manufacturers and distributors as well as service providers to network with key buyers from the local construction sector. The Cape Construction Expo hosts seven dedicated product zones across the interactive exhibition, catering to the entire construction industry value chain from concrete technologists to consulting engineers.
“The quality of professionals visiting our stand was very good, they were the right decision makers such as health and safety officers and procurement managers. We will definitely be back next year,” offers Terry Fowler, Coastal Sales Manager from BBF Safety Group and exhibitor at the 2018 edition. Over 90 companies join the experience every year by exhibiting their products and services and benefitting from the unique networking opportunities with professional groups such as architects, engineers, project managers, quantity surveyors, contractors and more. Increased collaboration in the sector promises to lend to more efficient project delivery across the province to complete more projects on budget and on time.n To find out more about this event and how to get involved, visit www.capeconstructionexpo.com
Full range of Pro Ikon Products available: • Compression Testing Machines • Cube Moulds • Slumpcone Sets • Concrete Test Hammers • And many more Our SANAS Accredited Force Calibration Laboratory can offer in-house and onsite calibrations on Compression Testing Machines
Contact us for more information
Protsurv Geo Centre (Pty) Ltd February 2019 CONCRETE TRENDS 35
Tel: +27 11 976-2070 Email: sales@protsurv.co.za Website: www.protsurv.co.za
CEMENT & CONCRETE TECHNOLOGY
Concrete’s structural integrity unmatched, says the TCI
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tructural integrity, durability, energy efficiency and fire resistance are just a few of the benefits concrete construction offers for the creation of infrastructure, says Bryan Perrie, MD of The Concrete Institute (TCI). Perrie says the strength of concrete elements in buildings is well understood by structural engineers, architects and contractors. This includes in-situ reinforced concrete, precast concrete, tilt-up, hybrid construction, and post-tensioned concrete elements. “South African design and construction codes regulate the structural requirements of concrete buildings to ensure that concrete structures are safe, with the capacity to cope with any permanent, imposed, wind and earthquake actions. For common spans, the relatively high mass of concrete floors leads to natural damping and low vibration. For more demanding applications, such as for laboratories or hospital operating theatres, the additional cost to meet stricter vibration criteria is negligible,” Perrie states. Concrete is renowned as one of the most durable materials on earth, so well-designed, well-constructed concrete ensures longevity in any structure. This results not only in lower energy expenditure in building new infrastructure or housing, but also in reduced maintenance and impact on use of finite resources. “The first line of defence against deterioration is good quality, impermeable concrete. In the case of reinforced concrete, the quality of the cover concrete is critical in protecting steel reinforcement from aggressive agents and fire. Good material choice, mix proportioning, and sound construction practice are vital to ensure durable concrete,” Perrie emphasises.
Ensuring concrete integrity and durability is essential to utilise the equity already in the existing structure and not to have to re-invest in materials and energy prematurely. Concrete’s energy efficiency is shown in many ways. The use of local materials in production of concrete minimises fuel costs for handling and transportation and, once in place, concrete offers significant energy savings over the lifetime of the structure. Most of the primary materials used in concrete are produced locally. Cement extenders and slag aggregates are secondary industrial products that would otherwise have required dumping. While cement factories are generally located close to their necessary raw materials, sources of aggregates and readymix plants can be placed near areas of demand – thereby reducing the energy required for transport. “The materials used in concrete furthermore make efficient use of natural resources and the potential for recycling at lifeend saves quarrying of virgin materials. Concrete mixes for readymix plants and precast yards are designed specifically to use aggregates sourced from local quarries – and more recently also from recycled concrete – which reduces fuel costs for transporting these materials. “The embodied energy in the construction of a structure is usually minimal compared with the energy likely to be consumed during the life or use-phase of a structure. In the case of roads and transport infrastructure, anything that reduces fuel consumption will have a major impact on the energy usage over the lifetime of a busy highway. A major Canadian study showed a 2.35% fuel saving by using concrete roads, with a subsequent reduction in the emission of polluting gases.” Perrie says another benefit of concrete structures is that concrete does not burn or emit any toxic substances during a fire. It will not produce smoke or drip molten particles. Thus concrete can be described as ‘fire resistant’. The concrete in structures, unlike other construction materials, generally requires no fireproofing or protection if appropriately designed. “This eliminates the time, cost, additional materials and labour required to provide separate fire protection measures. During a fire, the concrete cover will protect the steel reinforcement from buckling or yielding.” Concrete’s inherent fire resistance will restrict smoke from spreading and will largely maintain a building’s strength during a fire. After a fire, the continuing structural strength and reduction in smoke damage also reduce the magnitude of insurance claims. Concrete structures generally remain intact after a blaze, allowing for relatively quick repair and re-occupation, saving time, costs and materials. “Fire-damaged concrete buildings usually do not require demolishing or rebuilding so concrete structures protect life and preserve property, contributing to enhanced social and economic performance of the built environment – an important consideration for all property owners such as municipalities. “When aesthetic qualities of design flexibility and variety of finishes are added to the sustainability benefits of concrete, it is easy to see why it is the preferred building material for property owners, developers, designers and contractors,” Perrie concludes.n
The structural strength of concrete elements such as precast concrete (pictured) is well-known by all in the South African construction industry.
More information from Bryan Perrie, Tel: +27(0)11 315 0300 www.theconcreteinstitute.org.za
36 CONCRETE TRENDS February 2019
CEMENT & CONCRETE TECHNOLOGY
Lafarge offers water industry the solution for more durable concrete
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or more than 180 years, Lafarge has provided innovative solutions and high-tech cement and concrete materials that have built sustainable infrastructure for communities. Now a member of the LafargeHolcim international group, a global leader in building materials, the company continues to be at the forefront of its industry with advanced laboratories that meet the needs of today and anticipate the building needs of tomorrow. “In years to come, faced with daunting refurbishment costs, it is no use thinking ‘if only’ we had built with different materials,” says Lafarge’s Roelof Jacobs, Integrated Solutions and Innovation manager. “Faced with the demands of high population growth and rapid urbanisation, we owe it to our communities to build a longer service life into our concrete structures. We simply cannot afford to reconstruct or repair our raw, potable or waste water infrastructure every few years.” In constructing concrete infrastructure, frequently encountered problems are heat of hydration in mass pours and building in an aggressive environment with exposure to sulphate attack. One of Lafarge South Africa’s latest cement innovations, Sulf8-Cem, offers a solution for both of these challenges. Sulphates are said to ‘attack’ concrete because they can permeate the surface layers in solution with water, which then reacts with unreacted C3A and calcium hydroxide (Ca(OH)2) in the cement paste leading to the formation of various compounds that are far more voluminous than the original chemicals – as much as 600% or more! The outer layer of the concrete suffers cracking, spalling (surface layers bursting open) and separation of aggregate from the cement paste, leaving more surface area of the paste to react. In addition, any reinforcing then becomes exposed to corrosion and the progressive destruction of the concrete structure is well under way. Sulphates, especially in the form of salts of calcium, sodium, potassium and magnesium, are a challenge for concrete civil works in aggressive environments such as sewerage plants, abattoirs, areas exposed to mining activity common in areas where mines are operating and coastal areas where soil is high in sulphate. As a general guideline, if ground concentrations of sulphate are above 1000 ppm, ‘Sulphate Resistant’ cement should be used in concrete structures. The innovative solution, after extensive development at the renowned Lafarge Integrated Solutions and Innovation Centre (ISIC) in south-west Johannesburg (previously known as Quality Department Southern Africa [QDSA]), was Sulf8-Cem, a Low Heat (LH), Sulphate Resistant (SR) cement. Produced in bulk and bags at the company’s Lichtenburg Cement Works in North West Province and its Randfontein Grinding Station, the product is a CEM IV/B-V 42,5N LH SR Pozzolanic cement formulated from portland clinker with more than 36% selected quality siliceous fly ash, and C3A content in the clinker below 9%. The product also contains performance enhancing additives. Sulf8-Cem has been certified to conform to the latest applicable South African and European standards (SANS 50197-1 and EN 197-1).
“Reflecting our particular focus on developing a solution for constructing concrete civils infrastructure for the water industry, Sulf8-Cem also offers a significant benefit as a classified Low Heat of Hydration product,” comments Jacobs. The exothermic cement hydration reaction that rapidly raises the temperature of freshly placed concrete is not a problem in normal structures that allow the heat energy to dissipate easily. However, in large structures the heat builds up, causing high temperatures and expansion of the concrete while it is hardening. The temperature differential between the interior of a mass pour and the cooling outer layers can generate sufficient tensile stresses to cause cracking. Jacobs says that this not only reduces the bearing capacity of the structure but also creates entrance points for harmful substances to penetrate the concrete.
The innovative Sulf8-Cem will avoid costly repairs or reconstruction arising from sulphate attack. As a result of the high siliceous fly ash content in its innovative formulation, Sulf8-Cem is an exceptionally good Low Heat Pozzolanic Cement with a typical heat of hydration value of 166 J/g tested at 41 hours as per EN 196-9. While this contributes to lower peak temperatures with lower temperature differentials and the associated tensile stresses in mass concrete, the peak temperatures also occur at a later age, by which time the concrete is more mature and better able to withstand any tensile stresses. “At Lafarge, we set out to offer the water industry a solution for creating durable concrete structures suitable for use in aggressive environments,” concludes Jacobs. “We are extremely proud to have developed the all-round high performance product, Sulf8-Cem.”n More information from Natalie Johnson, Tel: +27(0)11 657 0000 Natalie.johnson@lafargeholcim.com www.lafarge.co.za
February 2019 CONCRETE TRENDS 37
CEMENT & CONCRETE TECHNOLOGY
Omani student proposes using tyre waste in construction sector By Shaddad Al Musalmy
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generated every year in the sultanate – yres are among the most problema figure that is projected to rise in line atic sources of waste because they with population growth and urbanisaare durable, non-biodegradable tion. For want of environmentally safe and can take up valuable space in landways of disposing of this waste, these fills. It was this problem that prompted a tyres have been piling up at two major student of Caledonian College of Engidumpsites. The biggest one is in Dhofar. neering (CCE) to come up with a novel In an effort to improve the durability way of using discarded tyres in the conand resilience of concrete, researchers struction sector. Fatma Sulaiman Nasser have attempted to use recycled rubber al Kindi, a chemical engineering student at CCE, said that discarded rubber tyres Fatma Sulaiman Nasser al Kindi, a student at CCE. within concrete mixes. The result of this has been positive as it has extended the are an environmental hazard worldwide. lifespan of concrete structures, roads and bridges. “I was thinking on how to make the best use of discarded tyres. Fatma said rubber tyres act as a binding agent. “The biggest I have noticed such tyres being dumped in open areas leading benefit is that it reduces the possibility of development of cracks to pollution in the environment. I embarked on the project of in concrete structures, roads or bridges. It helps to strengthen recycling tyre waste particles into concrete aggregate by an acid the quality of a structure.” treatment and an activation process,” she told Muscat Daily . Fatma said her method was environment-friendly. “I am usThe project is considered to find an alternative to the natural ing acid treatment to melt the tyres instead of burning them. aggregates used as filler in concrete. “Waste tyres will be conThis prevents any chemical reaction that may result due to their verted into small pieces and mixed with concrete mixture for burning in the presence of water vapour and sunlight.”n construction work as well as providing raw material to a number of different industries.” According to Be’ah, the UAE’s leading environmental manSource: https://goo.gl/3PxYRf agement company, 45,000 tonnes of ‘end-of-life’ tyres are
Is self-healing concrete the future of construction? By Dennis Daniel
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uilding cracks and deterioration are common points of concern for asset owners and managers alike, but a new technology may soon alleviate these industry issues. Researchers at the University of Cambridge are using microencapsulation technologies developed by Dolomite Microfluidics to develop self-healing construction materials. The university’s Department of Engineering’s Geotechnical and Environmental Research Group said recently that it is developing microcapsules containing ‘healing’ agents such as minerals, epoxy, or polyurethane which can be added to building materials to allow the self-repair of small cracks that develop over time. Commenting on the technology, a postdoctoral researcher in the group, Dr Livia Ribeiro De Souza, explained: “Many composite building materials used in the construction industry, such as concrete, suffer fatigue over time, causing the development of small cracks. “We are hoping to overcome this problem by adding microcapsules filled with ‘healing’ agents to the concrete before it is used. The idea is that as cracks begin to form, they rupture the microcapsules, thereby releasing their payload and stabilising the material. “This approach requires the formation and functionalisation of double emulsion microcapsules, which we have been producing with the help of microfluidics. We have been using
38 CONCRETE TRENDS February 2019
a Dolomite Microfluidics system since 2014, and find that microfluidics offers much better control of particle size and composition than traditional emulsification polymerisation techniques, simplifying the investigation and optimisation of particle properties,” explained De Souza. The Dolomite system has enabled the researchers to create functionalised microcapsules that bind more strongly to the cement matrix, while also having thinner shell walls and higher core retention, thus improving their self-healing properties. “Our discussions with experts at Dolomite Microfluidics are helping to accelerate our research and move us a step closer to real world applications,” De Souza concluded.n Source: https://goo.gl/SNFmyi
CAPE 11 - 12 September 2019 | Sun Exhibits, GrandWest, Cape Town
Do you want to grow your business in the Western Cape? Exhibiting or sponsoring at Cape Construction Expo is the best way to grow your professional network and increase your profits. Here’s what you will achieve by booking a stand:
Increase your sales by building a network of local agents and distributors who will resell your products.
Meet face-to-face with key buyers from the Western Cape region.
Gain ultimate brand exposure in front of a highly qualified audience.
Connect with small and medium contractors and ensure they source your products.
Book your stand today Contact us to get a tailored package designed for you. MarcelDuToit@dmgevents.com
+27 21 700 5500
www.capeconstructionexpo.com
PRODUCTS & SERVICES
a.b.e. polyurea waterproofing will protect a royal residence
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special a.b.e. Construction Chemicals waterproofing coating was selected for wide-spread sealing of surfaces being built at the new ultra-luxurious Royal Palace being built in Maseru. Boksburg-based a.b.e. is part of the Chryso Southern Africa Group. Noel Abendroth, a.b.e. Polyurea Performance Coatings Manager, says VIP Polyurea Quick Spray Industrial pure polyurea coating has so far been applied to over 2,400m2 of diverse surfaces at the Royal Palace now being constructed by LSP Construction of Maseru. The VIP polyurea sealant was specified by LSP which is carrying out the large-scaled contract for the Government of Lesotho. Among the areas of the palace sealed with the pure polyurea coating were:
An aerial view of the luxurious Royal Palace in Maseru.
• Palace roofs; • Roof gardens; • T anking for ground-level exotic gardens; • Guest house roof; and • Tennis Clubhouse roof. “The design of the palace called for waterproofing that was guaranteed not to leak, particularly as part of the roof gardens are on the roofs of the living quarters of King Letsie lll. Despite exceptionally warm and humid weather, a.b.e.’s approved polyurea applicators, Diamond Linings, by using high-pressure plural component spray equipment, managed to complete the project in just under a month,” Abendroth states. “It is expected A completed section of the polyurea waterproofing of the roof of the that further applications of the polyurea palace at Maseru. sealant will be needed for the extensive and spectacular exotic gardens.” * Capacity to transgress multiple substrates in He says VIP Quick Spray Polyurea can after proper preparaone application; tion be applied to concrete, metal, foam or other surfaces and * Application in any thickness is possible in a within seconds, builds a rubber-like elastic skin that will not single application; only resist punctures but has excellent resistance to heat distor* Strong sound insulation; tion and sagging as it maintains its flexibility and shape. The * Resistance to ultra-violet radiation, saltwater, and coating, once cured, is also not affected by moisture and copes aggressive atmospheric conditions; and with fluctuations of temperature with its high elongation and superior tensile strength,” he adds. * Coverage of large areas at a rapid rate. VIP Polyurea coatings – containing no VOCs and solvent-free a.b.e. Construction Chemicals holds an exclusive agreement – are designed to perform for around 25 years which substanwith VIP (Voelkel Industrie Produkte) in Germany for the local tially cuts the costs of repairs and maintenance. sale and distribution of the German company’s respected range Some of the many advantages of the VIP Polyurea Quick Spray coating include: * E xtremely fast reaction and curing times; different systems offer between 6 to 90 seconds gel times; * E xceptional adhesion to concrete, steel, aluminium, plastics, fibreglass, wood and foam; * Seamless and jointless flexible coating;
40 CONCRETE TRENDS February 2019
of protective coatings and joint fillers. Produced in Munich, VIP Polyurea coatings have been internationally hailed as a “new revolution in coating technology” and have set new benchmarks in terms of durability, protection, ease of application, and turnaround times.n More information from Elrene Smuts, Tel: +27(0)11 306 9000 / www.abe.co.za
PRODUCTS & SERVICES
Mapei’s modern flooring products save time
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tionally procured and graded raw he difference between the success and failure of a floor materials to ensure adhesion to lies both in the selection of the right flooring products and the company’s global standards.” the correct application of these products. This is critical to Mapei is busy building solid reensure the floor meets the end users’ requirements. lationships with many key appliThis is particularly relevant in today’s modern building envicators and encourages installers ronment where many new floor types have been introduced, and all business professionals to each with its own requirements and all-new fixing and finishing speak to its technical representaproducts that are required to correctly lay them. Although the Mapefloor products from Mapei. tives to find solutions for individprospect of seeking different solutions for each type of floor ual flooring requirements. may sound daunting to contractors used to installing tradition“We are eager to assist the local industry to improve efficiency al floor surfaces, it should not be, as modern systems are usuand ensure that we provide installers with the most suitable ally custom designed to ensure quicker and easier installation products and techniques to undertake any flooring. As new and high-quality finishes. flooring systems become available on the market, we make it Tracy Harris, commercial manager of Mapei, one of the bestour business to develop and constantly update and change our known suppliers of construction chemicals and flooring soluofferings to suit new requirements,” concludes Tracy.n tions in the world, says specifiers and installers should take the time to investigate new systems rather than relying on tradiMore information from Geoffrey Green, tional ways and simply trying to adapt them to suit new floor Tel: +27(0)11 552 8476 / email: g.green@mapei.co.za surfaces. “Where specially developed solutions exist, they will www.mapei.co.za usually be more cost effective and safer than modifying traditional methods, as well negating the risk of floors failing, either aesthetically or mechanically,” she says. Tracy explains that Mapei constantly researches and develops new screeds, adhesives, grouts and other flooring products to suit new floor styles. Therefore, the comIndustry leaders for over 40 years, find out why pany has an expansive range of flooring over 5000 businesses trust our products and expert levels support in policy development, products ranging from industrial solutions legal advice and after sales service. to commercial and retail products. These include cementitious, resin, polyurethane systems, water-based flooring systems, as well as consolidators which are used to preserve and maintain existing floors. As important as product selection is the corHigh speed testers capable of testing high volumes of people at site rect application and the techniques needed entrance/exit points and portable instruments with digital readouts for for different flooring types. For Mapei this use at remote sites providing immediate printed evidence. means ensuring provision of on-site support as well as providing effective technical training to Mapei-preferred applicators. “Our products, training and our ongoing The ALCONTROL Breathalyser is an unmanned breathalyser. Made to be rugged and simple to use. technical support aim to provide speed of The ALCONTROL can be used in any environment application, lower building and operating for operator free breathalyser testing. Ideal for costs for longer building lifetimes. Our incontrolling entrance at turnstile gates. dustrial flooring solution-based systems are developed for applications across all industry sectors in the industrial flooring market Strongest and fastest breath alcohol tester on the market. and are HACCP-compliant as well as carryAlcoBlow Rapid Test requires the smallest breath sample and ensures accurate results first time, every time. Results ing international certifications from Clean are obtained within seconds. Very economical operation, no Room associations. They are also easier disposable mouthpieces are required. The subject simply to maintain for end users, with no sealer blows into a cone at the end of the instrument. coats needed or additional maintenance Drug testing as easy as A, B, C... costs incurred for owners. “That’s why all Mapei’s products are Saliva sample collection in 1 - 2 minutes. Test accurately manufactured according to the strictest infor drugs in 5 minutes. ternational quality and sustainability standards. These are either manufactured at Ensuring safer working environments for over 40 years our large factory in Roodekop, Germiston Help is one call away +27 12 343 8114 or obtained from our global supply chain. or visit www.alcosafe.co.za for more information These are also manufactured using interna-
Alcohol and Drug testing specialists
February 2019 CONCRETE TRENDS 41
DIGITAL CONSTRUCTION
The future of BIM will not be BIM By Guest Authors
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What will be the next step decade ago, talk about once BIM methodology is BIM was only found in fully implemented as a convery specific research struction process? and development groups, as From my point of view, once well as some pioneer companies. this is achieved, the B (buildHowever, now the term BIM ing) and the M (modelling) has spread throughout the will be dissolved, and the I construction sector and the (information) will be the great building information modelling strength of this methodology. concept has become essential. The idea of modelling will BIM manager, parametric obbe totally integrated in the jects, common data environment, construction process and the 4D, 5D, asset lifecycle manageinformation will be the valument, LOD (level of developable point, already known as ment) and LOI (level of informabig data. tion) are day-to-day terms in the Image from www.directionsmag.com. Nowadays, big data is beAEC industry. ing developed in all the differDuring these last years, we ent business sectors. It is a key concept. As has been said, data have witnessed how the BIM methodology has progressively is the new gold. And this is also true for the construction sector. been implemented in many countries. This demand, which was We are all accustomed to industries such as banking or marketbefore the desire of a particular developer or a contractor ening using big data to set up their commercial strategies. hancement, is now a requirement and a reality in most complex For example, based on bank accounts and movements, fiprojects, in addition to being requested by public administranancial companies offer specific banking packages. Depending tions and employees. on consumer choices, specific discounts are offered for differDeveloping a project with BIM has evident, well-known ent products for supermarket shoppers. benefits. BIM provides an increase of the productivity and an This connection between construction work and big data improvement of a project´s workflow, a cost reduction in the will be through the development of a digital twin model. This construction process and a cut-down of execution times. Furmodel will be conceived as the result of integrating 3D images, thermore, BIM minimises human error and potential clashes, construction and design data, i-model, virtual and augmented allows easy analysis of the different stages of the project and reality, artificial intelligence, etc. improves communication between the different stakeholders. The digital twin provides the possibility of creating a virtual BIM is a reality today. The BIM market is forecast to grow from mock-up of the physical entity. Once this twin model is created, $3.58 billion in 2017 to $7.64 billion by 2022. In a short while, the amount of information linked will be enormous from the projects will be fully developed with the BIM methodology in a first establishment of the work and the early design. common and routine mode, in the same way that no one thinks This data collection and its subsequent use will be of the of detailing drawings by hand – it is done with CAD software. utmost importance. The model will be developed in parallel to This will take us to a point where, by default, projects can the building and will be fed by all agents throughout the conbe analysed in advance, giving rise to an industrialisation of struction of the building, as well as its subsequent use. construction work.
42 CONCRETE TRENDS February 2019
DIGITAL CONSTRUCTION In addition, and at the same time, it will be updated by the sensors inside the buildings. The sensors will send information about work performance, for example based on monitoring how materials are affected by climate and the passage of time. They can provide information about changes in energy efficiency or a structure’s behaviour. However, what is going to be the change in the AEC Industry? Based on the digital twin, simulations are carried out to make analyses and predictions. This will improve productivity, with a real impact on costs, and provide an opportunity to generate new business models. In other words, big data will allow us to deal with a large volume of data, both structured and unstructured. With this information, we will perform predictive and advanced analysis, helping us to make strategic decisions based on a prediction of behaviour as well as real data. This will allow us to minimise the error threshold and allow the possibility of making crucial decisions in real time. Furthermore, processing this huge volume of data will allow a more strategic view of construction projects and their status. The collection and analysis of this data will be really useful for construction companies to improve efficiency levels. Last but not least, this huge knowledge will also be an opportunity to optimise processes and improve outcomes in the construction sector. For instance, AI-enabled processes could be used in planning and scheduling activities, since they have the potential to evaluate endless combinations and alterna-
tives based on similar projects, optimising the best route and correcting themselves throughout the project stages. So what will happen when we reach that point? At that moment, the model will not be the working model as we know it today. The construction project will be developed with massive data schedules from data management software such as Excel, SAP or Oracle. The model will be just a photograph of that information, visual confirmation that the data makes sense and what we are creating is optimal. It will provide the proof that the data represents the desired viaduct, tunnel, complex structure or amoeba-shaped roof. It will be a digital pre-construction. The model will be the way to coordinate that huge amount of information generated between the different disciplines in the project. To sum up, in future construction will be developed in BIM methodology, because it will be the only way to develop complex projects. However, nobody will talk about BIM itself anymore. Each one in his role will see the information identified as important for that defined role, so that they can identify the strengths and weaknesses and achieve their objectives. It is important to emphasise at this point that training users for the tools and BIM methodology, along with its possibilities, is a key factor for the achievement of the project goals. The value of the user will be how he analyses and uses this information. As a result, HR will never again look for pure BIM profiles.n Source: https://goo.gl/A9yfB1
BIM: It’s your move – a new free ebook by Vaughan Harris
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hile there is no universally accepted definition of BIM yet, the truth is that Africa will never join the earlier adopters nor have the resources to accomplish the infrastructure development that Africa needs, unless we all work together and produce a new way of working on our continent,” says Vaughan Harris, president of the BIM Institute. “For many contractors, especially in South Africa, the profit margins have been very slim in recent years, and the unpredictability of the process poses risk for everyone from the client onward. The collapse of some ‘Big Five’ contractors in South Africa shows how real those risks are. Yet most contractors in Africa have failed to adopt new ways of working, resulting in the continent lagging far behind the rest of the world.” The new eBook BIM: It’s your move looks at the introduction of common global standards and operating methods using BIM and how Africa can benefit. It discusses the barriers to operation and trade across the African construction industry. Harris asks, “As a continent, how do we improve certainty of the construction output including increases in quality and reductions. Most important is how we can improve resource
bimacademyafrica@gmail.com | www.bimacademyafrica.co.za
efficiency using advanced construction software that’s been available locally for decades. “Many companies including the professional bodies will argue that they have invested in employee CPD training. However the ‘traditional CPD style’ of training by putting staff in a room for a few days and overwhelming them with ‘death by PowerPoint’ is a very dated way of thinking. We are in one of the most transformational times in human history, the opportunity now is to be liquid, to learn ‘just in time’ and not ‘just in case.’ “Technology has become far more than just a technological enabler of transformation but is an innovative tool leading us to news ways of processing information. “Today, millennials assimilate information and learn differently. We need to learn from this, we need to immerse ourselves in an interactive experience that takes us out of the head space of ‘business as usual’ – and into the head-space of being a digital investor,” concludes Harris.n 1
BIM - It’s your move
The eBook, BIM: It’s your move by Vaughan Harris, is downloadable free of charge at https://www.biminstitute.org.za/the-book-page/
February 2019 CONCRETE TRENDS 43
LAST WORD
Concrete recognised as “biggest homedesign trend of recent years” Internationally the perennial building material is moving indoors – and fast, Jan de Beer discovers.
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hile visiting Perth, I was delighted to read in The West Australian newspaper’s glossy colour magazine that concrete has now become a big hit indoors Down Under. Read this wisdom from the Aussies: “Once considered nothing more than a humble building material, concrete has become one of the biggest home-design trends of recent years.” The bit about a “humble building material” is, of course, highly arguable but for the sake of international relations let’s not in this column debate the alleged humility of a material used to build the Colosseum.
Two pieces of Studio Sment’s Gestalt Collection.
Part of Vanderbeke’s New Primitive Collection. Listing the attributes and appeal of a new range of handcrafted bathroom basins in three different shapes, the Perth magazine’s editor proclaimed that concrete had indeed “made a splash in the bathroom”. Well, all readers of Concrete Trends could have told her so long ago – and not only in wet areas of the home either. On the web, the news from Belgium tells us about two new developments in concrete furniture design: pigmentation and the recycling of concrete waste blocks to make Neolithiclooking furniture. In the first place, dark pigments were used to create the illusion of precious stones in a series of geometric concrete furniture by Belgian design studio, Sment. The Gestalt Collection comprises three objects: a tall, cylindrical lamp with a carved-out section that helps it gently reflect light back off the polished surface; a seat in the shape of an arch; and a low, ring-shaped table that sits on three squat feet. Each piece is cast in a mould with pigmented concrete.
44 CONCRETE TRENDS February 2019
The material is then polished to create the stone-like final effect. “We investigated several ways of using pigment,” says Sment co-founder, Jochen Sablon. “The combination of pigmentation with polishing leads to a surreal twist of organic patterns which reminds us of natural materials such as stone or marble. This together with the geometrical form produces an abstract sculpture for every piece.” The project aimed to find a new way to present concrete as a precious material. The lamp and the seat are made of solid concrete, while the table incorporates a loop of insulation material to make it lightweight enough for domestic usage. It has a terrazzo bottom for additional strength. The piece can also be dismantled, so that the top can be placed on its side when it is not in use. Based in Vilvoorde, Belgium, Sment was founded by Sablon (a practicing architect) and Frederik Bogaerts to investigate the potential of specific materials. “The research is always a balance between searching the boundaries of the material and the effective properties of the concrete itself. By emphasising the limitations of the moulds and enlarging them for The Gestalt Collection, we kept on refining the results until they were so pure that they almost became sculptures.” The Gestalt collection debuted at the Interieur Festival, an offshoot of Biennale Interieur 2018 in Kortrijk, Belgium in October 2018. Also in Belgium, Ghent-based designer, Bram Vanderbeke, has sculpted a series of abstract furniture pieces from blocks made of concrete waste that are treated with pigments and waxes to give an unexpected texture. The New Primitives Collection features a series of side tables and benches that have been treated with stone wax, commonly used to treat marble sculptures, to create textured furniture items that resemble neolithic structures. Inspired by the anthropocene era – the period in which human impact became the dominant force on earth’s geology. The aim of the project was to treat concrete like a natural material, which Vanderbeke believes makes it feel more valuable. “In the future, I believe that we will be able to harvest manmade materials just like we already harvest natural materials. I wanted to sculpt waste blocks of concrete and treat them like a sculptor would treat a valuable stone such as marble,” says Bram Vanderbeke. The side tables feature a round surface with four supporting legs. The pieces have a rugged texture resembling prehistoric structures made from natural stone. The benches, made of narrow rectangular blocks with four legs, feature a similar rough texture. Vanderbeke began by using an angle grinder to shape the concrete blocks, before treating them with rock polish and concrete pigment and varnish. “This gives the surface an unexpected and more valuable texture,” he adds. “I wanted to play with the surface and treat the concrete like a natural material. In this way, the concrete feels like a new natural material.”n For more information about the Belgian initiatives, visit the website www.dezeen.com.
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