ISSUE ONE • 2019
R49.00
THE VOICE OF THE PRECAST CONCRETE INDUSTRY
• PMSA invests in quality • CMACS takes off • UCT to research drainage
GLOBAL VIEW
3 PMSA – BUILT TO LAST
19 WEAR DEVELOPMENT
INDUSTRY NEWS
TECHNICAL
6
MANUFACTURERS SWITCH TO CMACS CERTIFICATION
7
AWARD OF EXCELLENCE
8
RAISING ABOVE THE PACK
9
FINDING ECONOMICAL USES FOR COAL ASH
22
10 OBITUARY: JOHN SIMPSON
12
CONTENTS
COVER STORY
33 34 FIRST GREEN HOUSING SOLUTION IN PRETORIA 35 PAVING POLOKWANE RESIDENTIAL AREA
26 AIR-PURIFYING CONCRETE
37 METRORAIL SAFET Y WALL
PROJECTS
38 LOCAL WINE PRODUCERS SWITCH TO CONCRETE FERMENTATION TANKS
27 PERMEABLE PARKING SPACE FOR SHOPPING MALL 28 PRECAST CONCRETE PANELS FOR V&A URBAN PARK
39 CAST-STONE PAVERS SELECTED FOR CAPE HOUSING
30 CARBON FIBRE PLATES STRENGTHEN ROOF SLABS
PRODUCTS 13 CONCRETE WITH CRACK HEALING PROPERTIES
40
15 SOFTWARE MAKES CRB WALL CONSTRUCTION EASIER
COMPANY NEWS
31
16 GATEWAY SCHOOL PUPILS LEARN THE ART OF CONCRETE 17 NEW SHOWROOM TO CELEBRATE 25TH YEAR
PRECAST is the mouthpiece for the Concrete Manufacturers’ Association - CMA Concrete Manufacturers’ Association Physical Address: Office 0400, Standard Plaza Building, 440 Hilda St, Hatfield, Pretoria Postal Address: Post Net Suite 334 Private Bag X 15, Menlo Park, 0102 Tel: (+27 11) 805 6742 Fax: (+27) 86 524 9216 E-mail: admin@cma.org.za Website: www.cma.org.za Publishers: Isikhova Publishing & Communications Postal Address: PO Box 651793, Benmore, 2010, South Africa Tel: (+27 11) 883 4627 Fax: (+27 11) 783 2677 Website: www.isikhova.co.za Publisher: Andrew Meyer Tel: (+27 11) 883 4627 E-mail: andrewm@isikhova.co.za Consulting editor: Raymond Campling Tel: 076 297 2775 E-mail: media@mediasavvy.biz
PRECAST | ISSUE ONE | 2019
41 DRONES MAY BE THE ANSWER TO RESOLVING DISPUTES 42 LOCAL MOULD MANUFACTURER CRAFTS WINNING FORMULA
Coastal editorial: David Beer Tel: 082 880 6726 E-mail: david.bigsky@gmail.com
ISSUE ONE • 2019
R49.00
THE VOICE OF THE PRECAST CONCRETE INDUSTRY
Advertising: Linda Meyer Cell: 083 626 8814 E-mail: linda.precast@gmail.com Subscriptions/Accounts/ Advertising Admin: Thuli Majola Tel: (+27 11) 883 4627 E-mail: subscriptions@isikhova.co.za • PMSA invests in quality • CMACS takes off
Design and layout: Joanne Brook E-mail: joanne.studio@isikhova.co.za The views and statements expressed in this publication are not necessarily those of the editor or the publishers and neither the publishers nor the CMA accept responsibility for them. No person connected with the publication of this journal will be liable for any loss or damage sustained as a result of action following any statements or opinions expressed herein. The same applies to all advertising. Precast© 2019. All rights reserved. No part of this magazine may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage retrieval system, without prior written permission from the publishers.
Endorsed by:
• UCT to research drainage
ON THE COVER PMSA is a privately-owned company which places a strategic importance on development. Its latest acquisition of high-tech equipment, facilities and skills is in line with its objective of building lasting relationships with customers that are based on the provision of quality equipment, efficient aftersales service and professional technical expertise.
1
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COVER STORY
While market conditions in the South African construction industry have been undeniably tough, the country’s leading concrete equipment manufacturer, PMSA (CMA non-producer member), has used the quieter times to expand its facilities to meet future demand.
3
During this period, the company has invested in the expansion of its own in-house metal service centre, including the acquisition of the largest fibre laser-cutting machine on the continent and fabrication equipment, as well as expanded workshops and auxiliary equipment. Simultaneously, it has bolstered its own in-house skills base to build upon its extensive after-sales services, which are key differentiators in an increasingly heavily traded market. PMSA director Walter Ebeling says the privately-owned company has always placed strategic importance on development and that the acquisition of hightech equipment, facilities and skills is in line with its objective of building lasting relationships with customers that are based on the provision of quality equipment, efficient after-sales service and professional technical expertise. Looking forward “We’re constantly looking ahead and improving the way we do business so that we remain ahead of the field in terms of
PMSA – BUILT TO LAST
our overall offering. In order to do so, we invest in quality equipment, quality processes and quality staff to ensure that our equipment will last a lifetime and will always be supported. In this way, we build relationships that last a lifetime too,” says Ebeling. “PMSA wants customers to form relationships with us where their needs are being met in every way, including production objectives, price per unit,
“We invest in quality equipment, quality processes and quality staff to ensure that our equipment will last a lifetime.”
(Above): Carefully welding components. (Below, from left): The showroom; PMSA installed the largest fibre laser-cutting machine on the continent.
availability, adaptability and everything else that’s important to each individual concrete manufacturer. “The company still has clients whose parents bought equipment from our parents 40 years ago. Those relationships are still going strong, as are many of the original machines. What’s important is that we know what our customers need now and what they might need in future. We therefore need to research and develop products and services that meet their expectations going forward. Customer-centric “Whether it be building custom machines for a client or creating financing deals
PRECAST | ISSUE ONE | 2019
INSTALL
CERTIFIED
PRECAST CONCRETE
PRODUCTS
TO OBTAIN A LIST OF CERTIFIED SUPPLIERS, CONTACT CMA CERTIFICATION SERVICES OR VISIT WWW.CMA.ORG.ZA.
Address: Office 0400, Standard Plaza Building, 440 Hilda Street, Hatfield, Pretoria, 0083 Tel: (011) 805 6742 • Email: admin@cma.org.za
IF YOU THINK PRECAST CONCRETE, THINK CMA
A
N
UF
ACTURER
S A OCI
NCRETE
SS
M
PRODUCER MEMBERS.
CO
AT I O N
al
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e
Q
u
it
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re
Address: Office 0400, Standard Plaza Building, 440 Hilda Street, Hatfield, Pretoria, 0083 Tel: (011) 805 6742 • Email: admin@cma.org.za • Website: www.cma.org.za
COVER STORY 5
(Above): PMSA holds more than R28 million worth of spares. (Top right): One of the company’s high-definition laser-cutters. (Right): Laser-cutting of oversize components is no problem.
to help them improve the quality of products, or even structuring deals that enable our customers to grow and prosper, that’s what we do best and want to continue doing. No other concrete equipment manufacturer in the country can boast the same gravity as PMSA, nor the same levels of customer service. “You can’t put a price tag on quality after-sales and support. PMSA is about quality manufacture and a large stockholding of spares and parts throughout the country. We’re also the only concrete equipment manufacturer that employs
He adds that PMSA pays careful
its own highly skilled, mobile field service
attention to helping businesses grow
teams throughout the country and around
through various life-cycles, from the
the world, wherever our machines are in
start-up phase through to automated
operation. Several of our field and support
operations and serving the biggest con-
staff have more than 20 years’ experience
crete manufacturers on the continent.
at PMSA with our equipment range. We solve the problems facing the market and
Developing opportunities
deliver equipment and services to meet
The investments by the company are part
changing requirements,” says Ebeling.
of the PMSA Built to Last™ business philosophy, which views the company as the market thought leader and largest single concrete equipment provider on the continent, building relationships and machinery that will endure for decades. This type of dedication to improving customers’ bottom lines is unique and underscores the importance for concrete manufacturers of keeping up to date with developments in the industry and upgrades of equipment in order to stay ahead of the pack.
PRECAST | ISSUE ONE | 2019
(Above): PMSA’s flagship Ultra-3000. (Left): P2000 mixers ready for dispatch to Middle East.
INDUSTRY NEWS 6
PRECAST CONCRETE MANUFACTURERS SWITCH TO CMACS CERTIFICATION Steadily growing numbers of precast
& Good Laboratory Practices Act of
concrete manufacturers are placing their
2006. This means it’s totally compliant
trust in Concrete Manufacturers’ Asso-
with the law and is fully equipped to audit
ciation Certification Services (CMACS)
and assess precast concrete products
for the certification of their products.
in line with internationally recognised
“CMACS offers the precast concrete
best-practice standards. The service
manufacturer a reliable SANAS-approved
itself is audited annually by SANAS
certification and quality auditing agency,”
and a committee comprised of external
says Henry Cockcroft, CMACS director
professionals ensures that its activities
and general manager of the Concrete
remain impartial.”
Manufacturers’ Association NPC (CMA). “It also provides a valuable service to
Quality certification
professionals who can now have direct
CMACS certificates are valid for three
access to the people involved in the
years and companies are audited twice
certification process.
annually. The process begins with a to-
“A major advantage of CMACS is
tal system audit. Quality management
that it specialises in precast concrete
systems such as ISO are checked and
certification and all its personnel are
validated, as are testing procedures and
professionals intimately acquainted with
documentation. Thereafter, product test-
motivation/specification is drafted by the
the various properties of the material.
ing to SANS specifications is conducted.
CMA in collaboration with the industry
Precast concrete is their exclusive
As an example, the standard require-
and sent to a SABS workgroup for re-
domain, so the auditing and testing
ment for the production of concrete
view. After circulation to the industry for
process is very focused, efficient and
r e t aining w all blo ck s
input and comment, revi-
quick, typically taking no more than
(CRB) SANS 508-2012
sion and fine-tuning, the
four to six weeks, provided no non-
is published in a 17-page
standard is approved by
conformities are identified.
do cumen t . Ma t er ials
the workgroup. It is then
which must meet speci-
typeset by the SABS in
Bringing stability
fied quality standards
SANS format and a proof
“Mor eover, because this is a CM A
in SA NS 508 include
is sent back to the work-
initiative, it’s designed as a service to
cemen t, aggr ega tes,
group for final revision.
the precast concrete industry. As such,
wa t er, pigmen t s and
Then, on behalf of the
it’s priced well below the going rate,
colouring. Dimensions
Department of Trade &
a factor which makes it accessible to
and nominal dimensions,
Industry – the curator
both the small and large producer,” adds
shape, compr essi v e
Cockcroft.
strength, slump, dry-
(Above): Henry Cockcroft of the CMA.
of all SANS standards – the document is
“We’ve already audited 14 precast
cast specifications and mass, which
allocated a SANS specification number
concrete manufacturers and issued
should not be less than 95% of the nomi-
and is published as an official SANS
CM A C S cer ti f ica tes in compliance
nal mass, also form part of the standard
standard by SABS.
with South African National Standards
requirements, as do application testing
[SANS] since CMACS was first granted
and marketing.
Cockcroft believes that standards are the very bedrock of a well-ordered
SANAS approval in August 2017. It’s
In addition to the certification work
society. “Chaos would reign without
had a stabilising influence on the precast
undertaken by CMACS, the CMA sits
them, which is why it’s so important
concrete industry. Everyone’s benefited
on a workgroup within the SABS which
that precast concrete manufacturers
– the manufacturer, the professional who
ini tia tes new and r e v ises ex isting
have ready access to a reputable and
specifies the product and, of course, the
standards. The workgroup comprises
af fordable cer tification agency,” he
end user, in the knowledge that CMACS
SABS personnel and a broad group of
says. “Judging from the feedback we’ve
certification guarantees performance
professionals, all of whom are involved
received, it appears that CMACS has
across 16 precast concrete SANS
with precast concrete.
boosted conf idence in the pr ecast
specifications. “CMACS was appointed an accredited
concrete industry. Architects, engineers Averting chaos
and other specifiers now know that
certification body by SANAS in terms
When the precast concrete industry re-
ther e’s a r eliable means of r eadily
of Section 22 of the Accreditation for
quires a standard to be updated or a new
sourcing precast concrete products
Conformity, Assessment, Calibration
standard needs to be initiated, a written
with officially sanctioned certification.”
PRECAST | ISSUE ONE | 2019
ICRI AWARD OF EXCELLENCE On 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, which took place in Omaha, Nebraska, USA. The award was presented to Sanika Waterproofing Specialists (a CMA non-producer member) for its professional concrete repair and waterproofing of the Anglo-American coal mine ventilation shaft at Goedehoop Colliery in Mpumalanga. The ICRI is an industry body consisting of world-renowned engineers, architects, manufacturers and contractors who host an annual awards ceremony to honour outstanding projects in the concrete repair industry, with over 50 project entries per year. This was a huge boost for the local concrete repair and rejuvenation market, as it revealed South African companies to be a formidable force in the international concrete repair industry. Approximately 7 000 litres of water were flooding into the shaft per minute through numerous cracks up to 300mm wide, creating a significant safety hazard and possible failure of the structure. An immediate and permanent solution had to be found to remedy this massive ingress of water. Numerous products were tried, but were unable to resist the enormous extent of water pressure which forced itself across the 9m diameter shaft. Not many products or applications in the market are able to be applied on the negative side against such pressures. Sanika’s professional expertise, combined with Kryton’s concrete waterproofing repair and rejuvenation products, successfully waterproofed the cracks and stopped the flooding. Furthermore, the structural integrity of the shaft was maintained, thus improving durability. 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 usable shaft. Kryton crystalline technology can withstand 14 bars (140m) of negative pressure, self-heals cracks up to 0,5mm and drastically decreases water permeability of the concrete. (Top): Brian MacNeil, ICRI’s regional manager: North America, presents director Paul Smit and technical sales director Colte Smit, both of Sanika Waterproofing Specialists, with the Award of Excellence.
PRECAST | ISSUE ONE | 2019
INDUSTRY NEWS 8
TRAINING COURSE TO RAISE PROFESSIONALS ABOVE THE PACK Construction industry professionals need
(Above and left): Concrete at its best.
only devote five days of their time for
(Below): John Roxburgh, senior lecturer at The Concrete Institute’s School of Concrete Technology.
intensive training in concrete technology to boost their own career opportunities
certification, professionals will command
and ensure that the structures they
respect in the construction industry and
design have the sustainability the South
be able to access wide-ranging, career-
African economy vitally requires.
boosting opportunities.
This is the view of John Roxburgh, senior
“Every construction company, cement
lecturer at The Concrete Institute’s
SCT30 Concrete Technology should be
producer, admixture supplier, ready-
School of Concrete Technology, who
their priority. The five-day course with
mixed concrete company, concrete
believes there is an alarming dearth of
laboratory sessions covers important
testing laboratory, precast concrete
civil engineers with sufficient knowledge
aspects such as:
factory, structural consulting firm,
of how concrete really works.
• Properties of concrete in fresh, early,
municipality, government department
“C oncr e te technolog y sk ills ar e
and hardened stages.
dealing with infrastructural development,
extremely scarce in SA, mainly because
• Concrete mix design and production.
architectural and quantity surveying
too many professionals are either not
• Mix design for specialised applications.
business, pr oject development and
prepared to devote time to studying the
• Off-shutter and architectural finishes.
subject or feel that such knowledge is
• Formwork, reinforcement and joints.
not vital in their profession. But with
• Defects, blemishes and repairs.
increasing press reports of structures
• Mixing water and chemical admixtures.
collapsing prematurely all over the world,
• Temperature’s effects on concrete
it is time for consultants to realise
quality.
that they simply cannot do without a
• Placing, compac tion, pr o tec tion
technological knowledge of concrete,”
he says.
and curing. Roxburgh says professionals who
successfully complete the SCT30 training Priority learning
course can increase their concrete skills
Roxburgh declar es that if civil and
with more advanced training, culminating
structural engineers – and architects
in the globally respected Advanced
– have time for only one training course,
Concrete Technology (ACT) certification.
the School of Concrete Technology’s
However, even if armed only with a SCT30
“The education and competencies gained from this course will enable a budding concrete technologist to immediately make valuable contributions.” PRECAST | ISSUE ONE | 2019
technology – and the SCT30 Concrete
technology issues not only for his or her
of a person competent in concrete
Technology course is the launching pad
company, but for the national construc-
technology,” he says.
for such ambitious professionals.
tion industry as a whole.”
“It provides a strong foundation to Ambitious professionals
all important concrete concepts, along
• The minimum entrance requirement
“That list is actually far from exhaustive.
with delving into more advanced con-
for the course is a Grade 12 education.
There are also the exciting and many-
crete mix design, cold and hot weather
For full details about qualification for
faceted fields of decorative concrete
concreting, special mix types and deal-
SCT30, as well as other courses planned
now increasingly emerging to further
ing with heat in mass concrete. The
for Midrand, Cape Town and Durban
illustrate the huge scope for concrete
education and competencies gained
by The School of Concrete Technology
technologists. The scarcity of concrete
from this course will enable a budding
in 2019, tel: (011) 315-0300, e-mail:
technologists is good news for anyone
concrete technologist to immediately
sct@theconcreteinstitute.org.za or
wanting to make a career out of concrete
make valuable contributions to concrete
visit: www.theconcreteinstitute.org.za.
FINDING ECONOMICAL USES FOR COAL ASH Mountains of ash from our coal-burning power stations can be avoided if new
About SACAA
uses can be found to convert it from
SACAA is the umbrella association
waste product to a valuable commodity.
for the producers, marketers,
Already some of the ash is making its
user s, uni v er si ti e s, r e se ar ch
way into the country’s cement products
organisations and individuals playing
to lend str ength and aid curing of
an active role in the promotion of
concrete, as well as having applications
responsible ash utilisation.
in agriculture, ground stabilisation and
Its purpose is to grow the indus-
other uses. But the combined offtake of
try for the development of its mem-
these is below 7% of the ash produced
bers and the benefit of the South
and needs to be boosted considerably
African economy, in compliance with
higher to 18%, if environmental goals are to be met.
the environmental legislation. (Above): Mark Hunter of SACAA.
SACAA is associated to most
For some time now, the SA Coal Ash
as uses in manufacturing, chemical in-
of the world’s Ash Associations
Association (SACAA) has been working
dustries, landscaping and other uses. We
and has had representation at
with government, environmental agencies
need only look at the amazing composition
World Ash Conferences, including
and business to develop solutions to
and structure of different types of ash
the presenting of papers, training
growing ash dumps. Simultaneously, the
produced in each power station, from fine
courses and poster stands.
aim is to alleviate other socio-economic
and potentially valuable fly-ash to coarse
issues affecting the population which, if
bottom ash and everything in between.
successful, can have positive and far-
For further information, contact Mark Hunter on tel: 083 631 0793,
“We simply need to challenge our
e-mail: mehunter22@icloud.com or
technical brains trust to look for applica-
visit: www.coalash.co.za. To con-
tions in their fields of work or study and
tact Aspasa, tel: (011) 791-3327
Take the challenge
to find ways of overcoming problems to
or e-mail: office@aspasa.co.za.
During a recent fact-finding tour of the
integrate ash into their supply chains.
Matimba and new Medupi power station,
And, for those who think this is an im-
SACAA general manager Mark Hunter
possible challenge, it’s worth noting that
revealed that research is underway to
certain countries in developed economies
This proves its worth and shows that
determine the viability of treating the
are using as much as 80% of their ash
with a little willpower and innovation,
scourge of acid mine drainage throughout
produced,” said Hunter.
SA’s powerful business and technical
reaching benefits.
the gold mining areas known as the Reef
superb Maputo Bridge in Mozambique.
sectors have the ability to solve the
with suitable coal ash. Certain building
Valuable elsewhere
growing ash dilemma, while at the same
products made with ash are also being
South African fly-ash and ash products
time using the free resource to over-
tested and reviewed for suitability to
were selected to enhance concrete used
come some of the biggest challenges of
alleviate housing shortages.
to build the world’s then tallest building,
the current generation.
“However, these aren’t new ideas and
the Burj Khalifa, as well as improving
SACAA recently joined forces with
we believe that a myriad of other uses
concrete used to construct the Katse
the large surface mining industry as-
exists for this waste product. There are
Dam, the highest, deepest and one of
sociation, Aspasa, to improve its reach
certainly more uses in civil engineering for
the largest water storage dams in the
to a similar and broader cross-section
roads, concrete structures, etc, as well
country, as well as the architecturally
of industries.
PRECAST | ISSUE ONE | 2019
INDUSTRY NEWS
management firm needs the services
9
INDUSTRY NEWS 10
OBITUARY: JOHN SIMPSON John Simpson died after a sustained ill-
Early days
was not very often. During the 1990s he
ness. He is survived by his wife Penny, his
John joined Anglovaal’s construction
assisted Grinaker Masonry through some
daughter Diane and his son, Bruce. A sec-
arm, Grinaker, as a financial manager in
difficult economic conditions and tight
ond son, Michael, tragically predeceased
1984, working for the supplies and ser-
budget constraints and, thanks to his
John in a motor car accident in 2012.
vices division. Comprising nine companies
input and guidance, the company emerged
John was born in Klerksdorp and, at
(Grinaker Pr ecast and
from that period with a
the age of 11, was sent to boarding school
Grinaker Duraset among
healthy balance sheet.
at St Andrew’s in Bloemfontein, where he
them), it also included a
While still with Gri-
matriculated in 1958. The following year
battery factory in Zimbab-
naker, John joined the
he enrolled for a CIS at Unisa. During his
we and a piling company.
CMA’s management com-
part-time studies, he worked as an arti-
He was promoted to Gri-
mittee in 2000 to run the
cled clerk for Whiteley Bros in Klerksdorp.
naker’s financial services
financial portfolio. In addi-
John and Penny were married in 1965
division in 1992 and a
tion, he participated in the
and in 1967 moved to Benoni, where they
year later, was appointed
association’s strategic
raised their children and established
as its finance director, a
planning and gave valuable
strong ties with the local community.
position he retained until
input regarding its direc-
He joined Anglovaal’s Hartebeesfontein
his retirement in 2003.
tion and development. He
Gold Mine as an accountant in 1966
B e side s b eing ex-
was also instrumental in
and, the following year, was transferred
tr emel y conscien tious
guiding the association’s
to its head office, where he worked for
– he was an early bird
transformation from be-
several Anglovaal subsidiaries, including
and always in the office
ing heavily dependent on
National Bolts. His professionalism and
no later than 7am – John
diligence did not go unnoticed and it was
was gregarious and outgoing. He got on
being largely self-financed, and it was
not long before he was given additional
well with everybody, but was also known
during this period that he was appointed
responsibilities.
to be tough when he needed to be, which
financial director.
the cement producers to
DID YOU KNOW
Sports-lover John had an enquiring mind and many extramural interests. A keen sportsman, he was a provincial water-skier for Western Transvaal. He played hockey for Western Transvaal/Griqualand West
IS AVAILABLE
and continued playing social hockey until he turned 50. He also loved outdoor activities, including gardening and bird-
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ing. He was knowledgeable about the bush and wildlife and, on one occasion, he walked with a herd of elephants for several hours, often being close enough to touch them. He was introduced to fishing – which developed into a passion – by his col-
ISSU
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016
league and good friend John Siebert, 0
R49.0
when they hired a houseboat on Lake Kariba in 1990. John returned the compliment by acquainting JS with the
THE
beneficial properties of whisky. Some
CMA
years later, the two Johns and their
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• 2018
A– E CM
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wives spent a week in Scotland, where
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they visited distilleries and developed a
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deeper understanding and appreciation of the noble spirit. Locally, John was a member of the Whisky Fraternity, an association comprising a dozen or
THE
so professionals who met on the last Thursday of every month to engage in lively conversation and sample some
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single malts and lesser-known whiskies.
• CM A • Cre CS und erta atin kes g sa • Se first fer awa work aud ll pro its plac tects es Stra nd
MA –
John was also a member of Alicats,
THE C
ST IN
TY CA
QUALI
RETE
CONC
an inf ormal trout-f ishing syndicate
which meets at a fishing resort near Dullstroom several times a year. The 12-member group also assembles every Friday for conversation and light refreshment in Johannesburg. Helping hand Last, but not least, John gave very generously of his time and professional expertise to the underprivileged and
VISIT ISSUU.COM AND SEARCH PRECAST MAGAZINE FOR CURRENT AND BACK ISSUES
ls g wal tainin s en re cost wer • Gre rpiece rs lo aste rato ral m tu • Vib itec arch n A •
•W orld beat • 3D ing bl prin ock ted mak • Exc house er ellen ce on disp lay
those in need. He was heavily involved with Paradigm Shift in community work which included counselling, mentoring and helping young entrepreneurs find
rs winne nges Award challe • CMA omic ctures g econ or stru • Easin convey of n utio • Evol
their feet. John is fondly remembered by the CMA and its members. He resigned from the association in 2017 and from then until he passed on, he spent much
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of his time mentoring small businesses and enjoying visits to his bushveld cottage next to the Kruger National Park. Precast and the CMA extend our condolences to Penny and the family on their sad loss.
PRECAST | ISSUE ONE | 2019
CONTACT LINDA MEYER ON MOBILE: 083 626 8814 OR EMAIL: LINDA.PRECAST@GMAIL.COM
CMA
– QU
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Y CA
S
A strong foundation for infrastructure success
NEW PALLETS FOR BRICK MANUFACTURER Cape Brick decided to invest in new production pallets from CMA member PMSA, the official dealer for myWood in SA. U p o n i n v e s t i g a t i o n, t h e supplier r ecommended that they test the new generation of UPadvanced pallets from my Wood. Cape Brick did so and, af ter thorough testing, was satisfied that the pallets’ high flexural strength, durable surface and good performance in a steam-curing system made them most suitable f or its manufacturing requirements. T he UPadvanced pallet is made with a wooden core and a plastic overlay. myWood started the development of this new product in 2014 and was able to get the patent for it in 2015. It was tested for more than three years by European customers of the company before starting sales in 2018. Specially developed “We put all our know-how of more than 30 years of production into this board,” says myWood sales manager Tobias Schmidt. “Using wood with mainly standing annual rings gives more stability to the board. By drying the wood to below 20% humidity, we can reduce the weight of the board and the deflection characteristics. “The elasticity modulus is 12 700N/mm2, which is better than most pallet types available on the market. The plastic covering ensures that the bottom of the bricks is smooth and flat, also enabling customers to produce large-dimension, high-quality products.” Anthony Gracie from Cape Brick is happy with the new myWood UPadvanced pallets. “We were looking for a high-quality pallet at a reasonable price,” he says. “The myWood boards combine the advantages of both plastic and wood. The wooden core makes the board solid and stiff and gives excellent vibration. The plastic covering prevents water from going into the board and gives a nice bottom surface finish to our bricks. By using the new UPadvanced production boards, we’ve succeeded in significantly reducing cycle times.” Cape Brick decided to purchase the UPadvanced with stainless steel C-profiles on the edges of the board and having 45° angles cut
ROCLA is South Africa’s leading manufacturer of pre-cast concrete products. Surpassing 100 years of product excellence, including pipes, culverts, manholes, poles, retaining walls, roadside furniture, sanitation and other related products within infrastructure development and related industries.
on the corners. myWood is offering the pallets in basically all common sizes up to 3m length. (Above): Tobias Schmidt of myWood with Anthony Gracie of Cape Brick and Gerrie Beukes of the PMSA.
About myWood myWood is the worldwide leading producer of wooden pallets. The company has about 270 employees and offers a variety of wooden products for the construction industry. The new UPadvanced is
Visit us on www.rocla.co.za for our nationwide branches
protected by German patent DE 20 2015 102 814. myWood has already been sold more than 50 000 of the new pallets.
PRECAST | ISSUE ONE | 2019
PRODUCTS 13
CONCRETE WITH CRACK-HEALING PROPERTIES
tionally accepted penetration depths are
Brouard says this test has frequently
tightness or impermeability of concrete.
been used in SA to evaluate the ef-
“The test method described in the
fectiveness of crystalline permeability-
European standard EN 12390-8 for
reducing admixtures. He cautions that
testing hardened concrete is arguably
these products do not waterproof con-
the most practical test method available
crete, but rather reduce the concrete’s
in SA,” he says.
An entire concrete structure can be transformed into an internationally
Up to standard
accepted watertight barrier with the
The standard stipulates the depth of
use of the crystalline permeability-
penetration of water under pressure
reducing admixture Chryso CWA 10,
to evaluate the watertightness of con-
from Chryso Southern Africa (a CMA
crete to liquid. A 50mm penetration
non-producer member).
depth is classified as being “imper-
This is according to Brenton Brouard,
meable with respect to potable water”
technical manager: concrete at Chryso
and a 30mm depth as being impermeable
Southern Africa, who says that interna-
w i th r e sp e c t t o w a t er c o n t aining aggressive substances. In some parts of the world, the 30mm depth applied to water containing aggressive sub(Top): An entire concrete structure can be transformed into an internationally accepted watertight barrier with the use of the crystalline permeability-reducing admixture Chryso CWA 10. (Left): Construction chemical specialist Chryso Southern Africa supplied its Chryso CWA 10 integral permeability-reducing admixture to the Temba Waterworks project.
PRECAST | ISSUE ONE | 2019
stances is lowered to 20mm.
used to describe the degree of water-
PRODUCTS 14
level of permeability and watertightness
Brouard highlights that watertight
“When used as recommended, it’s
to the internationally accepted levels;
concrete, also called impermeable con-
compatible with all Portland cements
some penetration of the liquid under
crete, is vital for any structure which
and their commonly associated SCMs,
pressure is still possible.
retains liquid under pressure. “The value
as well as most Chryso admixtures and
On the other hand, waterproofing
of the product is that it can reduce the
abe products,” adds Brouard. “In ad-
of concrete eliminates any penetration
ingress of liquid under pressure to inter-
dition, it doesn’t adversely affect the
of water into the concrete. This is ef-
nationally accepted levels. The concrete
slump, strength, air entrainment or
fected using various 100% waterproof
becomes a watertight barrier, with
workability of the concrete.”
membranes, which are applied in the
lasting, integral permeability-reducing
form of surface coatings of various
properties,” he stresses.
thicknesses. Whether it is positive or
The admixture is non-toxic and can be
negative permeability that needs to be
added to concrete at the time of batch-
reduced, this versatile admixture is ideal
ing, so there are no climatic restraints.
for concrete exposed to harsh condi-
This makes it process-friendly, allowing
tions. By reducing the permeability of
flexibility in construction scheduling.
(Below, from top): The total concrete work on the Temba Water Treatment Works project was 17 000m³, of which 14 000m³ contained Chryso CWA 10 in the mix; the Temba Water Treatment Works site is situated within the northernmost portion of the City of Tshwane Metropolitan Municipality. The Phase 5 extension of the waterworks site comprised the addition of a 30Ml/day module to the existing four phases.
concrete, Chryso CWA 10 protects it against chemicals, chlorides, seawater and corrosive groundwater. Crack repair The permeability of a concrete is directly linked to the continuity of its capillary network. The greater the levels of watertightness effected in concrete using Chryso CWA 10, the greater the level of discontinuity induced in the capillary network. This is because its active ingredients react in the presence of moisture, forming a dendritic crystalline structure throughout the entire concrete’s pore or capillary network. This means less chance of carbonation, alkali-aggregate reaction or corrosion of the concrete and its reinforcing steel. Being protected in this way from waterborne, soluble salts enhances the durability of the concrete and the structure itself. “Given the right conditions, it can even seal hairline cracks up to 0,4mm wide in the concrete,” says Brouard. “This is because its active ingredients react in the presence of moisture.” He adds that, in the absence of moisture, it will lie dormant. However, it will reactivate as soon as it encounters moisture. As long as moisture is present, crystals continue to grow within the concrete. Watertight barrier The dendritic crystalline formations take place within the existing crystalline structure of the concrete, so it is an integral system with no risk of debonding. The reduced permeability, as well as the corresponding improvement in chemicalresistant properties that can be affected by Chryso CWA 10, will remain even if the concrete surface has been damaged.
“Given the right conditions, it can even seal hairline cracks up to 0,4mm wide.” PRECAST | ISSUE ONE | 2019
NEW DESIGN SOFTWARE MAKES CRB WALL CONSTRUCTION EASIER CMA member Terraforce has launched
(inclination) and wall width into account,”
a new software package, Maxiwall Pro,
says Terraforce MD Holger Rust.
for the design of concrete retaining block
Once a design is completed, Maxiwall
(CRB) walls. The software is a privately
Pr o also allows the ex por t o f wall
labelled version of the world’s most
geometries, soil and loading conditions
comprehensive and widely used CRB
to specific global stability sof tware
design software – the Vespa Mechanical
programs.
Stabilised Earth (MSE) design suite.
Rust cautions, however, that Maxiwall
Maxiwall Pro allows designers to
Pro is a professional analysis tool and
easily produce complete wall designs
should only be operated by designers
using Terraforce’s award-winning line of
and engineers well versed in CRB design.
CRB products. With all block and geogrid
“We’ve provided simple, easy-to-follow
information pre-loaded, designers can
design tutorials with Maxiwall Pro. These
select from a wide range of proven
cover the generic version of Vespa MSE
Terraforce systems from easily navigable
design software, but generally apply to
drop-down menus.
Terraforce CRB wall design.
Maxiwall Pro increases design efficiency, improves accuracy and promotes
Free software
a seamless flow of information between
“Our first design software, Maxiforce
design stages and parties. It generates
2000, was launched in 2004, followed
full wall layouts with accurate quantity
closely by Terrasafe, a retaining wall
estimates and comprehensive reports.
design service that provided first-class
In addition, its calculation engine can
engineering, management and specialist
simultaneously run static, seismic and
technical assistance to users of any of
internal compound stability analysis in
the Terraforce products.
accordance with NCMA, AASHTO (LRFD),
“Many complementary publications
Australian Standard, British Standard
per taining to block speci f ica tions,
and local design methodologies.
sustainability, plantability and irrigation, together with at least 250 project
Professional tool
profiles, have been made available by
CAD cross-sections and elevation views
Terraforce over the years,” says Rust.
are automatically generated and ready for import into AutoCAD using a Drawing
Maxiwall Pro is available at no charge to CRB design engineers.
Interchange Format output feature. Users also have the option of buying a copy of the AWall CAD tool, which allows them to accurately present plans and elevation views on grading plans. “AWall can create elevations and generate quantities in a ‘real’ wall footprint and takes variable wall height, wall batter
PRECAST | ISSUE ONE | 2019
“AWall can create elevations and generate quantities in a ‘real’ wall footprint.”
COMPANY NEWS
(Right): The success of this initiative is one to which all AfriSam employees proudly contribute as they take Caleon Garden Creations pupils under their wing.
More pupils at The Gateway School for special education needs in Roodepoort, Johannesburg, were recently empowered
16
in the art of concrete creations. Through a structured mentorship pr ogramme under taken by pr ecast concrete manufacturer Caleon Garden Creations, pupils 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 pupils as they prepare to graduate. The Gateway School’s focus is helping children with special needs realise their full potential by providing excellent educational opportunities and developing each pupil holistically. This includes empowering them with the skills and knowledge they need in the world of work. In doing so, the school of ten collaborates with corporates to expose the youngsters to various skills and has partnered with Caleon Garden Creations for the past four years. Outdoor furniture pleasure to impart skills that these
range of concrete products such as
GATEWAY SCHOOL PUPILS LEARN THE ART OF CONCRETE
tables, benches, pots and water features.
part to make this initiative succeed.”
there were people who understood its
AfriSam recently came on board to support Caleon Garden Creations in this worthy cause. In the programme, batches of three or four pupils at a time are placed under the wing of the company’s management and employees. With a factory in Rietfontein, Caleon Garden Creations manufactures a wide
Its products epitomise creativity and artistry in the use of concrete.
Upon completion of their practical block, a recent batch of pupils were
pupils can use. Hopefully, we’ve inspired them to build on those skills and create their own businesses in the future. With each group who joins us, we’re inspired anew by the commitment from the school.” The school’s occupational therapist, Karen Botha, said it was touched that pupils’ needs and were committed to helping this cause.
For AfriSam, with its commitment to
excited to show of f their creations
“Our continued par tnership with
community upliftment and empowerment,
and exuded confidence in working with
Caleon Garden Creations and now with
this initiative represents a fitting cause.
concr e te. I t was a pr oud momen t
AfriSam gives our pupils opportunities
The company’s own efforts are focused
for all involved as they witnessed the
t o l e a r n n e w s k i l l s,” s a i d B o t h a .
on projects that are sustainable and
achievements of these youngsters and
“More importantly, it helps them build
enable the beneficiaries to become self-
their enthusiasm in showcasing their art.
confidence in their abilities and shows
Speaking at the event, Caleon Garden
them how much more they’re capable
sufficient.
Creations owner Ferdi de Wit said the Teaching skills
initiative was the company’s way of
“We’re very excited to be a part of this
contributing to the upliftment of society.
initiative and are inspired to see the work Caleon Garden Creations has been doing
Kind tradition
with The Gateway School,” says Adele
“For my team and me, working with
Wentzel, sales manager for AfriSam.
The Gateway School is a heartwarming
“Going forward, we’d like to continue in
tradition that we’re proud to carry
this partnership and ensure we do our
through,” said De Wit. “It’s our greatest
of. For that, we’re grateful.”
“Pupils are being given the opportunity to create their own art using concrete.” PRECAST | ISSUE ONE | 2019
COMPANY NEWS
(Right): Adrien Desmarais of Progressive Paving, Revelstone founder and director Andrew Cyprianos, Mike Reynolds of Cape Flora Landscaping and Revelstone managing director Alex Cyprianos at the launch of Revelstone’s new showroom.
17
REVELSTONE LAUNCHES NEW SHOWROOM AND CELEBRATES 25TH YEAR CMA producer member Revelstone, one
Revelstone was founded by Andrew
of the country’s leading manufacturers
Cyprianos in 1993 and initially operated
of cast-stone products, celebrated its
from an underground cellar in Muizenberg.
25th year by launching a new showroom
Its reputation for product development,
in Lansdowne, Cape Town.
innovation and quality personalised
Designed as a landscaping idea hub
service spread rapidly, catapulting the
for architects, landscapers, interior
company to the pre-eminent position it
designers, building contractors and home-
commands today.
owners, the showroom is a visual feast,
Cast-stone products are durable,
showcasing a wide range of Revelstone
recyclable, cost-ef fective, versatile,
paving, cladding and coping for both
energy-efficient and innovative.
outdoor landscaping and various indoor
“Natural stone products are becom-
applications. In addition to a double-
ing more expensive and less environmen-
volume exhibition space, the showroom
tally friendly, and are generally imported,”
boasts a boardroom for meetings and
said Cyprianos. “By contrast, our prod-
demonstrations on a large screen, an
ucts are produced using 95% local raw
outdoor garden area and a coffee bar.
materials located within 100km from our
Speaking at the launch on 13 September, Revelstone managing director
factory. In addition, all our moulds are 100% recyclable.
Alex Cyprianos said the facility is a forum
“Our pr oduc ts ar e almost in-
aimed at inspiring design creativity in the
distinguishable from natural stone and
built environment.
w e u s e t r a d i t i o n a l m a s o n r y sk i l l s
“We’re encouraging all our clients, be
combined with a modern moulding tech-
they home-owners or landscape architects,
nique to painstakingly reproduce an
to use this space to meet and collaborate
original master, which is then used to
in a relaxed atmosphere,” he added.
create a mould.”
PRECAST | ISSUE ONE | 2019
WEAR DEVELOPMENT Moulds are among the most important parts of the concrete manufacturing process as they play a direct role in the overall costs and quality of products produced.
regular maintenance, however, these
abrasive material contributes more to
defects are only found in exceptional
wear than finer-grained aggregates.
cases in most concrete block plants. Upper-edge wear Wear at the upper edge of the mould occurs much more frequently and can similarly be attributed to various causes.
Good moulds produce good products and
A central aspect here is the centering
bad moulds do not. That is the long and
of the mould in the machine. There is
the short of it, according to Chris Hense
no system on the machine side that
of specialist mould manufacturer Kobra
can optimally align the mould and keep
Moulds in the Netherlands. High-quality
it in this position during the production
moulds produce economical and well-
process. Kobra moulds have a gap of
made products that fetch higher prices
four-10ths of a millimetre on all sides
on the market than poorly-made ones. It is essential to use the best-quality
Figure 1: Checking for wear at the lower edge of the mould
moulds possible to ensure the overall quality of products and thus ensure the efficiency and profitability of a plant.
between tamper shoe and stone cavity in order to ensure the smooth plunging of the tamper head into the mould cavities.
Increased wear at the lower edge
However, in order to keep the mould
of the mould can also occur if the
c en tr e d dur ing the manu f ac tur ing
As one of the world’s leading mould
relation between the vibration power
pr ocess, ther e is a distance of at
pr o duc er s, K obr a F or men GmbH
and frequency settings is not balanced in
least 1mm on all sides in the machine,
offers not only the development and
the machine (ie not adjusted to suit the
depending on the make – larger than
manufacture of concrete block moulds,
respective product) and the vibration is
the gap between tamper shoe and
but also their maintenance and repair.
too strong.
stone cavity. The result can be one-
Kobra has compiled a list of typical signs
“Since consistent centering cannot be guaranteed on the part of the machine, this type of wearing should be checked on a regular basis.”
sided loading of the mould, since the
of wear and their causes. “ T he c oncr e t e blo ck mould is a precision tool that combines numerous functions for the manufacture of highquality products,” says Hense. “However, even the best moulds are subject to wear and this may lower the value of end-products if the tool wears to the point where it becomes defective.” He therefore advises manufacturers to look for the following signs of wear:
lateral forces will move the mould and the tamper shoes will therefore make contact with the tops of the cavity walls each time they plunge into the mould during the compaction process. Since consistent centering cannot be guaranteed on the part of the machine, this type of wearing should be checked on a regular basis. One way to reduce such wear is by periodically replacing the plastic strips that assist in keeping the mould bottom centred in the machine.
Lower-edge wear
A further interaction exists between
The experience of Kobra service
the vibration power and the mould
Mould surplus
engineers shows that wear at the lower
contact pressure. This should not be set
One of the internationally observable
edge of the mould only occurs very rarely
too low or the mould will lift up from the
trends in the concrete block manufac-
today. The causes of such wear could be
board and material will flow out. In this
turing process is production with a small
mechanical (ie in the machine itself) or
scenario, the concrete runs underneath
mould surplus. According to Kobra, the
due to various incorrect settings.
the mould, which can wear enormously.
normal mould surplus standard can be
Mechanically related wear can occur,
If, on the other hand, the mould contact
explained by the following example:
due to damaged rubber buffers on the
pressure is too high, the mould will be
A concrete block is to have a height
vibrating table or broken bearings on the
overloaded and the vibration power of the
of 80mm and a shoe chamfer and insert
mould clamps. Cracks in the vibrating
machine absorbed. Therefore a product-
chamfer of 4mm each. The mould height is
table, the machine frame or defective
related co-ordination of vibration power
92mm. Therefore, due to the difference
production boards can also contribute
and contact pressure is necessary.
between the block and mould heights,
to higher wear, since the mould is
Ultimately, the type of materials used
there is an insert depth of 12mm around,
subjected to greater stress. Thanks to
also plays a decisive role. Strongly
which can adequately dissipate the
PRECAST | ISSUE ONE | 2019
GLOBAL VIEW
PRODUCTION TRENDS AND
19
GLOBAL VIEW
forces created from the tamper head to the mould during main compaction. If the block height (including the chamfer and insert chamfer) is the same, but the mould height is now only 88mm, the insert depth is only 8mm high around during main compaction. Wear is
20
increased because less area is available to dissipate the forces.
Figure 4: Heavy wear at the upper edge of the mould
Figure 2: Mould with normal mould surplus
Figure 3: Mould with low mould surplus
upper side of the mould because the
based compulsory centering known as
damage is only minor, then the tamper
Headguide™, which has been successfully
shoes must be separately adapted to the
used for years. Headguide guarantees a
changed dimensions of the stone cavi-
play of two-10ths of a millimetre around so
ties. The tamper shoes are aligned at the
that the tamper shoes and stone cavities
narrowest point in the mould cavity, with
cannot touch each other.
the aforementioned gap of four-10ths of
Thanks to the special design of the
a millimetre around. This results in a sig-
centering bushing, the mould can move
nificantly larger tamper shoe play in the
more freely, compared with solutions
worn areas of the stone cavities, which in
from other manufacturers, but is at the
turn can lead to sharp protruding edges on
same time consistently guided. The wear
the block. The possible replacement of the
of tamper shoes and the upper edge of
tamper shoes by trained technical person-
the mould is greatly minimised, since the
nel should be considered in order to ensure
guide bolts of the compulsory centering
constant quality of the concrete blocks.
ensure precise plunging of the tamper
If the production settings provide
Many of the listed causes of wear
head into the mould cavities. In addition,
for over-filling of the mould, the tamper
in concrete block moulds, which are
metallic abrasion and the so-called
shoes “swim” on the concrete before
precision tools, can be attributed to the
“bloom” formation are avoided.
plunging into the stone cavities when
poor and impermanent centering of the
Nevertheless, regular checking and
the tamper head is lowered during the
mould in the machine; however, this is
correction of the machine settings
compaction process. Characteristic in
important for a high-quality end product.
are important, since Headguide cannot
this case is one-sided wear at the upper
As a result, Kobra developed the mould-
correct improper machine settings.
edge of the mould during main compaction, if the aforementioned centering of the mould in the machine is not ensured. The tamper shoes strike against the stone cavities and damage the chamfers. At this moment, there is no centering or guiding between mould and tamper head. As a result, the wear at the upper edge of the mould may be too much for a repair to be viable. If the wear is as bad (as shown in Fig 5), there is no possibility of performing a repair weld on the upper edge of the mould, since the heat-affected zone around the welding seam is too high and the hardness necessary for long-term production is lost. A repair, which can be very complex and therefore highly expensive, is only of short-term benefit, since heavy wear typically occurs next to the welding seam. In addition, the stresses induced by the heat input during welding can result in an increased risk of cracking. If no repairs are carried out to the
Figure 5: The Kobra Headguide™ forced centering device
PRECAST | ISSUE ONE | 2019
from the material structure by heating.
application of the hardness grades
Economical and sustainable work in the
Through sudden cooling (quenching), the
most suitable for a particular concrete
manufacture of a product is only possible
elements are prevented from remixing.
b l o c k m o u l d, c o m p r e h e n s i v e h i g h
with suitable machines and tools. In the
At this point in the process, the steel is
wear-resistance can be achieved with
production of concrete products using
certainly very hard, but also extremely
significantly extended mould stability.
vibration technology, the mould is subject
brittle, so further processing for mould
to high mechanical stress. A durable tool
construction would be impossible.
is essential for mass production and the demand for the greatest possible wearresistance in the concrete block mould is therefore understandable. The mechanical stress on the mould tool can certainly be reduced by the correct machine settings, but not prevented. Therefore the wear-resistance of the steel material must be increased. Kobra has developed hardening processes matched to the particular mould type.
“The mechanical stress on the mould tool can certainly be reduced by the correct machine settings, but not prevented.”
The basis is different heat treatments
In addition, Kobra has developed a
GLOBAL VIEW
Increasing wear-resistance
system in which all feedback concerning the use of the mould is recorded, enabling conclusions to be drawn regarding possible improvements. Engineers, designers, production technicians and sales employees work closely together in order to offer the customer the best possible service in the after-sales phase and to minimise damage-related production losses. Kobra aims to form partnerships with its customers and offers much more than the manufacture of a tool. Support and transfer of knowledge,
of the material which alter its structure
Record-keeping
from the development and manufacture
by means of a tested temperature-time
The required material properties are
of a concrete block mould up to its
progression that produces the desired
therefore only established in the next
use, ar e principal r equir ements o f
hardness properties.
step of tempering. The steel has a
Kobra’s philosophy, which the company
Optimill Nitro® and Optimill Carbo-
harder surface and a depth of hardness
has successfully applied worldwide for
68Plus® are possible in Kobra’s in-house
that is suitable for use in the machine.
more than 25 years. Kobra produces all
hardening facilities. Basically, both pro-
The core has an optimal toughness for
possible types of moulds for all possible
cedures involve the separation of carbon
further processing. Thanks to standard
types of block machines.
21
TECHNICAL 22
The Civil Engineering Department of the University of Cape Town (UCT) has embarked on a research programme which aims to improve the performance of South African permeable paving in-
UCT RESEARCHES LOCAL
PERMEABLE PAVING PE
stallations. Locally introduced 10 years
or nature-based hydrological cycle.
ago, initial evidence suggests that perm-
“Unlike attenuation ponds, swales
eable paving is not meeting its objectives
or bio-cells, permeable paving doesn’t
of successfully retarding the short-
require additional space. This is why
circuiting of stormwater discharge, nor
it’s being widely used in Cape Town’s
the elimination of contaminants from
urban environment, where the City’s
stormwater run-off.
Management of Urban Stormwater
The research work is being spear-
Impacts Policy (2009) mandates the
headed by Neil Armitage, deputy-director
rate at which water can be released
of Future Water and a professor in
into stormwater infrastructure and
UCT’s Department of Civil Engineering.
the quality or purity of the water.
He is being assisted by a working group
Our data shows that none of Cape
comprised of professionals and some civil
Town’s installations – and, we assume,
engineering students.
permeable paving installations in other
“Our research effort is twin-pronged:
par ts of the country as well – are
gathering field data from permeable
functioning at any where near their
paving sites throughout the country,
current practice in SA is to simply copy
while simultaneously conducting
overseas design guides in the hope
optimal design parameters. “Blockage is the chief inhibitor of
laboratory experiments,” says Armitage.
that they work, without due regard to
permeable pav ing per f ormance and
“Our fieldwork focuses on the rate
differing environmental conditions. Our
all the systems we’ve tested exhibit
of stormwater infiltration, while our
prime objective is to devise a system
it, some more than others. Blocking
lab work deals with the removal of
or systems which work best under local
has several causes, including wind-
contaminants.
conditions and to then provide evidence-
blown sand (especially in Cape Town),
“As yet, there’s no national standard
based guidelines aimed at ensuring
vegetable matter, litter and cigarette
f o r t h e d e s i g n, c o n s t r u c t i o n a n d
much-improved systems which mimic, a
butts. It’s also caused by an internal
maintenance of permeable paving. The
closely as possible, the pre-development
build-up of sludge due to accumulated
PRECAST | ISSUE ONE | 2019
our team has been involved is right here on
(Left): Washing the aggregate in the UCT laboratory.
area which was constructed outside
(Below): The SWIFT test bucket.
the New Engineering Building [NEB] six
campus. It’s a permeable paving parking
years ago. Using the SWIFT method, a sand-infested bedding grit which was
Master’s student examined the water
then replaced with clean grit. Once this
infiltration capacity of 60 locations
operation had taken place, the paved
situated within 13 sections. Her tests
surface remained blocked. The removal
revealed five unblocked, two semi-blocked
of a few paving blocks then revealed that
and six fully blocked sections. The worst
some of the dirt had been blown into,
blocking took place on the perimeter of
rather than out of, the installation and
the parking area, which was subject to
was wedged between the pavers and the
the incursion of vegetable matter from
geotextile membrane,” explains Armitage.
the adjacent flower beds and trees.
“ W h a t d o e sn’t h e l p u s i s t h a t
Hardly surprisingly, the best or least
some countries have got away with no
blocked section was in the centre of the
maintenance for a long time. For example,
parking lot, furthest from the vegetation.
an installation over 20 years old in
“Given that it’s very hard to measure
Hamburg, Germany, has apparently never
the quality of water that passes through
been maintained and is still functioning,
a permeable paving system, we had
albeit only partially. However, the area in
three sumps built for water sampling
question is very large and is situated in a
dur ing c o n s t r u c t i o n o f t h e NE B’s
soggy regular rainfall environment, with no
parking lot. The first simply receives
wind-blown sand. And because permeable
contaminated r oo f r un-o f f without
paving has a design safety factor of 10
any filtration. The second is fed with
[ie 10 times anticipated run-on], one can
stormwater after infiltrating through a
theoretically have 90% blockage before
geotextile membrane and three layers
failure occurs. By contrast, most South
of aggregate. The layout for the last
African installations tend to be much
sump was the same as for the second,
smaller and, besides being subject to
except that we removed the geotextile.
wind-blown sand, are often situated close
In theory, the water in sumps two and
to vegetation and trees. This means that
three should be relatively clean. That’s
contaminants, especially in installations
a 90% blockage can occur in six months.
the theory, but the practice turned out
in which geofabric membrane has been
In fact, if landscaping soil is dumped on
to be somewhat different.
laid as a filtering mechanism below the
a permeable paving surface, a blockage
bedding course.
can occur instantly.
ERFORMANCE
“During construction of the NEB’s parking area, we replicated the test
“Unwashed aggregate is another
“There are various methods of test-
sections feeding through sumps two
cause for concern and is one of the
ing the infiltration rate of permeable
and three using exactly the same design
major reasons permeable paving systems
paving. We’ve found the international
and materials in the laborator y so
aren’t removing contaminants as they’re
and A merican standar d to be ver y
that we could run tests in a controlled
designed to do. In fact, our recent
onerous and slow. They involve sealing
environment. Then we built two further,
laboratory experiments have shown
the outside of a permeameter ring with
completely different designs.
tha t unwashed aggr ega te ac tuall y
a special putty and recording the time
“Our testing on all f our layouts
exacerbates water quality.
it takes for water to infiltrate. It’s
involved simulating Cape Town’s average
“Regular maintenance/cleaning is the
almost impossible to get it to function
annual rainfall of 20 storms of 5mm
only way of combating blocking. However,
properly because there are always gaps
and above. And although we used clean
very little is being done in SA, even
through which the water leaks.
tap water, what we got out was full of
though it’s stipulated in all the guidelines.
“Instead, we’re using a simpler test
contaminants. Even after several cycles,
Cleaning is complicated and, as yet,
– the SWIFT method, devised in Queens-
we only achieved marginal improvement.
there’s no fail-safe methodology. Various
land, Australia. It uses a wooden frame
Then we started doing projections and
systems are employed such as sweeping,
and a bucket which releases six litres
regression analysis to work out how
vacuuming, blowing with compressed air
of water through a 14mm hole onto the
long it would take before the water was
and spraying with water, all with limited
paved surface. It’s a very quick test and
squeaky-clean. Our projections indicated
degrees of success, or no success at all.
uses much less water than the American
that this could take well over 10 years.
“For instance, we recently witnessed
one. It works on the basis of water im-
In the end, we got tired of the process
a cleaning operation at Steen Villa, a
print on the paved surface. The smaller
and told the student to flood and flush
residential complex in Cape Town, where
the imprint, the better the infiltration
out test samples. He did that and things
compressed air was used to remove
rate and vice versa,” says Armitage.
started to improve.
PRECAST | ISSUE ONE | 2019
TECHNICAL
“One of the field test sites with which
(Far left): Prof Neil Armitage and civil engineering and permeable paving research student Kimberly Liu pose next to the 10 experimental permeable paving cells at UCT’s civil engineering laboratory.
23
TECHNICAL 24
“Then we stripped all four installa-
free. It was only after we’d brushed all
systems for North Carolina’s government.
tions and found a thick sludge layer at
the surfaces that the aggregate was
When I returned, we began experimenting
the bottom of each base course, which
clean. Thereafter, when we poured in clean
with some of the things he was doing.
was clearly going to be there forever.
water, we got out clean water. We then
For example, not using geotextiles and,
That’s when we became aware that the
reconstructed our test bins using prop-
instead, using sumps at the bottom of
aggregate wasn’t clean, even though the
erly cleaned aggregate,” says Armitage.
permeable paving installations to create
suppliers claimed it had been washed. We
“At that stage, I visited Prof Bill
aerobic zones – the theory being that
tried different cleaning methods using
Hunt of the USA’s North Carolina State
one can’t stop the ingress of dirt, so one
water hoses, but after letting it dry for
University, who’s conducting research
should rather let it settle at the bottom
two days, it still wasn’t contaminant-
into low-impact sustainable drainage
and take out the treated water from there. This is in contrast to the British AQUApave® system, which treats the water just under the bedding course. Of course, there are downsides to both systems. One gets blocked geotextile at the top and the other needs a storage facility, which uses more stone. “The quality of stormwater and level of contaminants varies greatly. But it would appear that nitrates and phosphates are the major culprits, because they’re widely used in garden fertilisers. One of our research students identified a commercially available fertiliser with a ratio of nitrates to phosphates which allows us to dilute it to the typical concentrations one finds in stormwater. T hat’s now our proxy for mimicking polluted stormwater.
(Above): The NEB parking lot blocked up with tree foliage and wind-blown soil.
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than to our conditions, which are hot and
with some field experience: consultants,
dry. Hence the American idea of using
contractors, suppliers, etc who’r e
nutrient-enriched tap water, measuring
a sump seems more suitable for local
prepared to share information about
the difference in results with untreated
conditions because a permanent pool of
their particular installations and designs,
tap water in 10 experimental cells in our
water provides a much better chance of
even if it’s just anecdotal. The more
laboratory using the same rainfall and
creating a permanent bacteria culture
feedback we receive, the more likely we
contamination regimes. Three cells in-
to handle the incoming food load. Even if
are to find a pattern. We should then be
clude a geotextile and some have missing
it’s just ticking over, it’s ready – at least,
able to begin building a permeable paving
stone layers. Each uses a different type
that’s our current thinking – and we’re
design guideline based on experiences
of paving and stone support system. The
willing to try it as a more effective way
across SA,” says Armitage.
bottom of each layout is perforated so
of improving water quality.
that we can remove sampling material. “Unfortunately, we don’t have the lux-
“We’re also eager to try other ideas. I’m particularly interested in people
(Left): Water samples for testing. (Below): The unblocked middle section of the NEB parking lot.
ury of changing one parameter at a time. So, in trying to hone down very quickly
UCT calls for help with
which systems are and aren’t working,
permeable paving research
we’ve had to take a shotgun approach.
Neil Armitage, deputy-director of
“One of the areas we’re investigating
Future Water and a professor in
is what happens during dry periods – for
the Department of Civil Engineering
example, when the geotextile dries out
at the University of Cape Town, has
and bacterial activity ceases. When
initiated a working group comprised
it rains again, it has to re-seed, much
of professionals and civil engineering
like a septic tank does. It’s therefore
students to conduct research into
possible that the use of a geotextile is
how to improve the performance of
better suited to soggy British weather
permeable paving systems and the quality of stormwater in a South African context. Armitage is seeking data and feedback from anyone involved with permeable paving, either in the supply of materials or its design and installation aspects, as well as its maintenance and upkeep. He is particularly interested in people in the field – ie consultants, contractors and suppliers – who are willing to share some details about their particular installations. He can be reached on tel: (021) 650 2589 or, preferably, via email at: Neil.Armitage@uct.ac.za
Permeable paving seminars set for May
Town (27 May), Durban (29 May) and
cleaning mechanisms for permeable
Ryan Winston, an assistant professor
Bloemfontein (30 May). They will be
paving installations, is widely published
at the USA’s Ohio State University,
organised by UCT’s Prof Neil Armitage
in technical and academic journals,
will be staging seven seminars
and are being funded by the Water
and has lectured at numerous
based on his research in the design,
Resear ch Commission. Delegates
conferences, workshops and seminars
construction and maintenance of
qualif y for continuing professional
in the USA and internationally. He
permeable pavements in that country.
development points.
received his MS and PhD at North
The seminars are free and are aimed
Winston is an internationally
Carolina State University studying
at civil engineers, landscape archi-
recognised exper t on sustainable
under Dr Bill Hunt and also worked as a
tects, town planners, paving con-
solutions for urban water problems
research engineer for him, overseeing
tractors and permeable paving
a n d, b e s i d e s c o l l a b o r a t i n g w i t h
construction of and research into
material suppliers. They are being held
Armitage in SA, shares information
urban stormwater control measures.
in Johannesburg (21 May), Pretoria
with colleagues in Sweden, France and
For seminar reservations, e-mail
(22 May), Knysna (23 May), Cape
Australia. He has researched several
Kim Liu at: LXXBOD001@myuct.ac.za.
PRECAST | ISSUE ONE | 2019
TECHNICAL
“This means we can now repeat the typical Cape Town rainy season using
25
TECHNICAL 26
AIR-PURIFYING CONCRETE CAN REDUCE
ATMOSPHERIC POLLUTION The use of air-purifying concrete in both
ing the prospect of lining tunnels with
pavements and surrounding structures
air-purifying concrete tiles combined
can play a major role in the reduction of
with conventional lighting,” says Perrie.
atmospheric pollution in urban areas, says Bryan Perrie, MD of The Concrete
Slow process
Institute.
As far as carbon dioxide uptake by con-
Perrie says air pollution is a steadily
crete is concerned, the process is gener-
increasing problem in densely populated
ally very slow, but can be deleterious to
areas and towns, with the most signifi-
concrete in that it can promote the cor-
cant pollution caused by fine particulate
rosion of steel reinforcement. This is not a
matter, volatile organic compounds
problem for concrete pavements because:
(VOCs) and nitrous oxides.
• Jointed plain concrete is not rein-
“When nitrous oxides are present
forced and carbonation is therefore
concurrently with VOCs, they lead to
fect in the laboratory. In these tests,
ozone formation and amplify the impact
the conversion of nitrogen dioxide as
• In continuously reinforced concrete,
of the fine articulate matter. It’s impor-
the result of a single contact between
the reinforcement lies at a depth of
tant to limit traffic emis-
the air and the photo-
60mm or more, depending on the
sions as much as possible,
ca tal y tic ma ter ial was
design. “This is sufficient to ensure
primarily by limiting the
determined: reductions of
that the reinforcement zone remains
traffic and therefore the
30-95% were measured.
untouched by the carbonation front
emissions. This is where
Efficiency in real-life ap-
during the lifetime of a pavement,”
concrete pavements and
plications aren’t entirely
says Perrie.
concrete structures in
dependent on the efficiency
He adds that pavement concrete is of
the immediate vicinity of
of the photocatalytic ma-
an exceptionally high quality and dense,
the pavements can assist
terial itself, but also on the
with few pores. The carbonation depth –
in reducing the effect of
contact quantity of air and
which is proportional to the square root
contact time between the
of the duration of the exposure – is only
air and the surface, the
likely to be 5-10mm after a period of 40
effect by using titanium dioxide on the
light intensity, relative humidity and the
years. In addition, because of the supe-
pavement and/or the structure’s sur-
amount and type of pollution present in
rior quality of pavement concrete, its
face,” he explains.
the air,” Perrie explains.
uptake of carbon dioxide is limited. How-
Neutralising effect
Testing continues
the absorption of carbon dioxide from the
When exposed to ultra-violet light,
He says the use of photocatalytic mate-
atmosphere increases significantly when
titanium dioxide acts as a catalyst
rials in the surface layer of a twin-layer
the concrete is demolished or crushed.
converting harmful compounds such as
concrete pavement or in thin concrete
nitrogen monoxide and nitrogen dioxide
overlays were tested at the Porte de
Slow leaching
into nitrates. These nitrates settle on
Vanves in Paris. Two 300m sections of
“Research from the Nordic Innovation
the surface and are washed away by
a busy street used by 13 000 vehicles a
Centre has indicated that as much as
rainfall. The nitrogen dioxide – which can
day were repaved as follows:
57% of the carbon dioxide emitted due to
lead to ozone formation, acid rain and
• One section with conventional con-
the calcination process in the manufac-
the emissions. It’s possible
(Above): Bryan Perrie, MD of The Concrete Institute.
to achieve an air-purifying
not harmful.
ever, the concrete will still carbonate and
the formation of particulate matter – is captured from the air. Photocataly tic materials such as titanium dioxide can also capture harmful
crete paving. • Another section with an experimental
thin concrete overlay using cement
with a photocatalytic action.
ture of cement will be reabsorbed by the concrete over 100 years,” says Perrie. As far as hazardous leaching products are concerned, tests have shown that
organic compounds from the air by caus-
“Measurements of the air quality and
the leaching behaviour of pavement con-
ing it to dissociate. The titanium dioxide
the surface water run-off were carried
crete – including both pavement-quality
is added separately to the concrete
out over the course of a year. It was then
and lean concrete – is totally harmless
mix. Alternatively, specially formulated
found that nitrogen dioxide contamina-
to the environment. “In fact, the quanti-
cements can be used which contain nano-
tion was cut by about 20%. Research
ties of heavy metals leached out turned
particles of titanium dioxide.
also revealed that the photocatalytic
out to be lower than the quantities that
“Various research projects have
reaction took place in ordinary visible
occur naturally in the mineral water sold
demonstrated the photocatalytic ef-
light, not only in ultra-violet light, open-
in stores,” he adds.
PRECAST | ISSUE ONE | 2019
PROJECTS
Permeable paving has been used in combination with asphalt paving to extend the parking capacity at Checkers Langverwacht Plein, a shopping mall on Langverwacht Rd in Kuils River, Cape Town. Completed during November 2018, the new parking area was required to provide additional bays f or building
27
extensions to the mall. PermeaLock paving blocks, supplied by CMA producer member CEL Paving Products, were used for the permeable surface. Designed by KLS Consulting Engineers, the installation complies with Cape Town’s City’s Management of Urban Stormwater Impacts Policy, which aims to reduce the negative impact of impermeable surfaces on aquatic eco-systems. K L S C o nsul ting E ngin e er s ga v e Checkers the option of installing either a small retention dam or a permeable paving system. The retailer opted for the latter, primarily because it did not require additional space. Instead, it forms an integral part of the parking lot, unlike attenuation ponds, which use up valuable space that might otherwise be used for parking or building purposes. Retaining water KLS associate engineer Carien Visser says permeable paving effectively retains a high percentage of stormwater on site and ensures that any water not infiltrated into the ground under the paving is released into the council’s stormwater system in a controlled manner via fin drains. “Moreover, the system’s layered sub-base structure of stones and locally manufactured geotextile membranes filters out most of the pollutants, including hydrocarbons, phosphorus, nitrogen and heavy metals. Our design was based on the assumption that 30% of the sub-base volume would comprise voids in which water is stored prior to dispersion into the ground or stormwater system,” she says.
PERMEABLE PAVING SYSTEM ADDS PARKING SPACE FOR SHOPPING MALL
The new parking area is situated on a
area revealed ugly oil stains on the
Asphalting. Starting from the bottom,
2 050m² site on Kloof Ave opposite the
parking bay surfaces. Therefore the
the permeable layered structure com-
main retail complex. The surface area of
parking bays were paved with asphalt to
prises a compacted sub-grade, a layer
the permeable paving is 830m², repre-
prevent oil from entering the permeable
of geotextile, a layer of 543mm clean
senting 40% of the total catchment area.
paving system and to minimise the impact
crushed stone, a layer of 19mm clean
of oil stains. The asphalt parking bay
crushed stone, a second layer of geotex-
Preventing oil ingress
sections fall towards and drain into the
tile, a layer of 6mm clean stone bedding
“Initially, the intention had been to cover
driveways which comprise the permeable
and screeding grit installed under and be-
the parking bays with the permeable
paving section,” adds Visser.
tween the PermeaLock paving blocks.
paving and the driveways with asphalt.
The sub-base layers were installed by
However, this application was reversed
Umzali Civils, the asphalt by ATS and the
after an inspection of the main parking
paving was done by Greystone Paving &
PRECAST | ISSUE ONE | 2019
(Above): The Checkers Langverwacht Plein permeable paving parking extension during construction.
PROJECTS 28
PRECAST CONCRETE PANELS FOR V&A Precast concrete panels have been used
sterdam Battery, which was built by the
This versatility, whether structural
to clad a structure at the V&A Water-
Dutch in 1784. This provided both a chal-
or decorative, provided an end-product
front urban park development, Battery
lenge and an opportunity for the design
that shows off exceptionally detailed
Park. Dubbed the Interpretation Pavilion,
and construction teams – paying homage
and finished concrete elements. It also
the concrete-clad structure references
to a historic landmark, while providing
references the robust nature of the
the site’s historical significance and links
leisure and parking spaces.
original Amsterdam Battery and the
the park, piazza and four-storey parkade via internal elevators.
The material palette includes a selec-
precast elements allowed for off-site
tion of hardy materials such as steel,
production and quality control. Cast in
Designed by dhk Architects to provide
an attractive light grey/off-white, the
new pedestrian routes and engage with
precast cladding for the Interpretation
the greater Cape Town community, Bat-
Pavilion was designed by dhk to create
tery Park includes an elevated park and
a façade in harmony with the other
lower-level piazza that effectively conceal
architectural themes at Battery Park.
a 1 206-bay parking facility. Situated along Dock Rd, a prominent entry point
Complex casting
to the V&A from Cape Town’s CBD, the
N u m b e r i n g 12 3, t h e p a n e l s w e r e
urban park plays a vitally important role
produced by CMA producer member
in terms of pedestrian traffic and con-
C oncr e te Units. T hey co ver ed f i ve
nects various V&A districts to the city
ex ternal elevations, as well as the
centre. In addition, the development fa-
internal walls of two elevator lobbies.
cilitates various recreational activities,
They also lined three splayed rectangular
including open-air events, skateboarding,
gun ports in the upper elevator lobby to
basketball, mini-football, swimming and
accommodate defunct cannons, much as
SUP rowing.
they would have done in an old fort or a
As the City of Cape Town no longer
man-’o-war.
promotes the vision of stand-alone
The smooth-bore muzzle-loading rel-
parking structures, the V&A required
ics date back to the 18th century and
a design that would utilise the upper
were discovered during site excavations
and lower “lef tover” spaces of the
at the V&A. Eighty percent of the panels
parkade. The need for a parking facility
had to be custom-made, with the re-
coincided with the proposal for a new urban park that would serve as a nucleus for a larger urban vision. dhk addressed these r equir ements by designing a
(Above, from top): The upper-level community park which effectively conceals the parkade below; the canal-facing piazza and behind it, a well-disguised parkade.
maining standard-sized units measuring 2 550 x 650 x 120mm. “Each panel required a full set of shop drawings and we used adjustable
publicly accessible park above the park-
stone and concrete, which suit the robust
moulds with large sof fits to accom-
ing facility and a piazza with space for
nature of the park. Concrete was chosen
modate the various shapes and sizes,”
shops and restaurants facing onto the
as “the material of our time”, since it is
says Concrete Units manager Brian
Roggebaai Canal.
clearly distinguishable from the historic
Cook. “Every unit was drawn in 3D and
elements. Both in situ and precast, the
our boilermakers had to take particular
Historical site
concrete used throughout the urban park
care in producing high-quality moulds.
The site also contains remnants of one
was of a high quality and included a variety
Avoiding casting lines and shutter joints,
of the city’s oldest structures, the Am-
of finishes and inventive applications.
the moulds also yielded crisp corners.
PRECAST | ISSUE ONE | 2019
tower crane. “Built with steel girders and measuring 4 400 x 1 145mm, the placement beam gave us not only finer vertical and horizontal adjustment, but also the required
PROJECTS
beam, which we suspended from the
reach for installing panels inside the two elevator foyers. Nevertheless, where possible and for sake of simplicity and speed, some of the external panelling was installed using a normal spreader beam. “And again, unlike the panel installation at Silo No 1, where a combination of corbels and dowels was the primary
A URBAN PARK
“This left us with no alternative but to
attachment mechanism, the panels at
use the main contractor’s tower crane.
Battery Park were bolted onto a galva-
Moreover, we had no access inside the
nised steel frame.
Heavy lifting
building, which meant that these panels
“We also supplied three-sided C panel-
“However, our biggest challenge on this
were also installed using the tower crane.
ling, which was attached to some of the
project was panel installation. Each
external beams at the entrance to the
weighed between 200kg and 1 500kg, the
Panel placement
upper-level elevator foyer, which used
latter being the maximum carrying capac-
“However, there was a problem with this
grouted dowels,” adds Cook.
ity of the main contractor’s tower crane.
solution. The tower crane only catered
“Whereas we used our own crane for
f or coar se adjustments of r oughly
the installation of the panelling at the
100mm increments and we were working
V&A’s No 1 Silo, we weren’t able to do so
with 15mm gaps between panels, which
at Battery Park because the perimeter of
of course required finer adjustment.
the structure resembled a five-sided poly-
T he solution involved designing and
gon, which required multiple crane set-ups.
assembling our own panel placement
(Top, from left): Precast concrete cladding supplied by Concrete Units was designed by dhk Architects to create a façade in harmony with the other Battery Park architectural themes; the upper section of the Interpretation Pavilion. It includes lined wall cavities for display purposes and gun ports for two muzzle-loaders, 18th-century rusted relics from the original Amsterdam Battery.
29
PROJECTS 30
CARBON FIBRE PLATES STRENGTHEN GATEWAY ROOF SLABS The conversion of a roof parking area
a leading position in the development
sidiaries in 100 countries around the
at Umhlanga’s Gateway Mall into ad-
and production of systems and products
world and manufactures in over 200
ditional shops and a hotel meant that
for bonding, sealing, damping, reinforcing
f a c t o r i e s . I t s m o r e t h a n 18 0 0 0
concrete beams and roof slabs had to
and protecting in the building sector
employees generated annual sales of
be strengthened to take the additional
and automotive industry. It has sub-
CHF6,25 billion in 2017.
loading which the conversion entailed. This was achieved by bonding Sika Carbodur carbon fibre plate, S1014 (7 300m) to the beams and roof slab soffits using Sikadur-30. Sika Carbodur plates are pultruded carbon fibrereinforced polymer laminates designed for strengthening concrete, masonry and steel structures. Sikadur-30 is a primerless structural epoxy adhesive which bonds Sika Carbodur to concrete, masonry and steel. The high strength and excellent durability of the Sika Carbodur made it the ideal choice for this application. Challenging time constraints (contractor Amsteele Systems was given only six weeks to complete the project) meant that the correct products needed to be applied effectively and quickly. Sika (a CMA non-producer member) is a specialty chemicals company with
(Above): The partially completed roof reinforcing at Gateway Mall using Sika Carbodur.
A NAME TRULY CAST IN CONCRETE
GAUTENG | KZN | WESTERN CAPE
PRECAST CONSTRUCTION SOLUTIONS HEAD OFFICE: (011) 589 8800 WWW.ECHO.CO.ZA
PROJECTS 31 In addition to the precast concrete cladding used on the Interpretation Pavilion at Battery Park, several other precast concrete elements were specified by dhk Architects for the construction of this urban park and parking facility development. These included concrete plinths to support the two historic cannons mounted inside the elevator foyer, a precast staircase with seat treads which leads from the piazza to the upper-level recreation area and precast concrete benches, as well as precast concrete paving on the upper-level park and recreation area which was supplied by CMA producer member Revelstone. The central concrete staircase and the steps adjacent to the canal were finished with off-shutter precast concrete treads, while some sections of the upperlevel park were paved with Revelstone’s Jura Cobble and Jura Paver pavers. Approximately 40 concrete moulds were used for the precast concrete stair treads and seats and 10 moulds were required for the precast benches in the piazza. All the moulds were adjusted by
FURTHER PRECAST ELEMENTS ENHANCE BATTERY PARK PRECINCT the insertion of loose stop-ends which
with an acrylic compound. The polishing
were made of either timber or concrete.
was done with wall-mounted table-top
The cannon bases and corner bench slabs
machines and hand-held machines.
were cast in timber moulds. The bench
Recycled course aggregate, Philippi
slabs were cast on a concrete table, each
sand and OPC were used for the bench
one measured to suit.
casting. No curing agent was used in
The treads were made using OPC and
either the precast benches or the treads
quarry dust from Afrimat’s Palmiet quar-
due to the possibility of colour variation.
ry, which had enough fines to preclude
They were simply cured for longer.
the need for additional sand. The tread mixture also included exposed aggregate for a non-slip surface and SIKA Lite for water-resistance and additional surface enhancement. After initial curing, the treads were washed, polished and sealed
PRECAST | ISSUE ONE | 2019
(Above, left): The precast concrete seat staircase and seat treads. (Above): Revelstone’s Jura Cobbles provide some of the hard landscaping on one of the Battery Park walkways. (Left): Jura Paver stepping stones lead onto the mini-soccer pitch at Battery Park.
PROJETCS 32
HERITAGE AND FUTURE
that it glows for up to eight hours during
Concrete has been synonymous with durable infrastructure – and thus civilisation itself – since the earliest times. Thanks to ongoing R&D, it looks set to be the building material of the future as well.
power consumption. Perhaps we are not
darkness – a great boon for lighting up walkways and the like, thereby reducing far off concrete embedded with sensors that provide data to building managers. One thing is certain: innovation will
Any civilisation is all about its struc-
new qualities, such as plasticity and the
not stop and will ensure that concrete
tures – not only palaces, temples and
ability to flow easily, as well as the crea-
remains not only one of the most de-
government buildings, but also public
tion of new types of surface and colour.
pendable and durable building materials,
spaces and the homes o f or dinar y
Concrete has gone from being seen
but also one that increasingly allows
citizens. A successful civilisation must
as a relatively utilitarian building mate-
us to create whatever we can imagine.
also be able to build infrastructure to
rial to one that can achieve spectacular
facilitate the movement of people and goods, and bring water to urban dwellers. Concrete has been, and remains, one of the key building materials for all of this vital infrastructure. Daniel van der Merwe, innovation architect at PPC Group Services, says that whereas Middle Eastern builders traditionally used a paste of burnt limestone to protect their clay buildings, in today’s high-rise structures, concrete has changed construction
“Concrete has gone from being seen as a relatively utilitarian building material to one that can achieve spectacular aesthetic effects.”
Improving society Concr ete is mor e than an integral enabler of the infrastructure a civilisation needs – it can also be used to create structures and spaces which are intended to realise ideals. Thus while roads, dams and office blocks, etc, are critical pieces of infrastructure, they basically support the status quo. However, other types of structure have a purpose which is further-reaching and helps transform society. It is this type of transformative in-
methods beyond all recognition, thanks to intensive and continuous research
aesthetic effects: one has only to think
frastructure that grabs PPC’s collective
and development by scientists and the
of the famous “sails” of the Sydney Op-
imagination and underlies some of the
major suppliers themselves.
era House. Indeed, nowadays concrete is
exciting projects we are involved in as
even being used successfully to fashion
part of our corporate social investment
sculptures and jewellery.
initiatives. They showcase not only con-
Better product As a result, not only is concrete more
In similar vein, we are also seeing
crete’s versatility as a building material,
durable and easier to work with, but a
concrete with added aluminium silica
but also its ability to support new ideas
bewildering array of additives have added
which absorbs light during the day so
in the real world.
PRECAST | ISSUE ONE | 2019
being imposed on it. The project is
Conceived by artist Erhardt Thiel, the
ongoing and plans to repair and expand
iMadiba project aims to create public
1to1 – Agency of Engagement at Slovo
the community hall are advanced. This
spaces across SA that encourage dia-
Park, south of Soweto. The idea was
new initiative aims to empower the
logue between all citizens by providing
born out of a student project and aimed
local youth forum both by doing the work
a place to sit and have conversations.
to change the way this politically sensi-
and then using the hall to undertake
tive informal settlement was regarded,
various projects.
Three installations have been unveiled (Robben Island Gateway, the V&A Wa-
to create a common space that would
Slovo Park is a pilot for a larger
terfront and outside the Johannesburg
have the buy-in of the community, thus
programme aiming to start 25 such
Stock Exchange (JSE)) and more are
providing a foundation for development.
projects by 2020. Like this one, they all
planned. Concrete truly is the material
aim to realise PPC’s purpose of helping
not only of the past and present, but
everybody enjoy a better quality of life.
also – as these examples show – for
Community input
PROJECTS
One example is the collaboration between PPC and non-profit organisation
A n impor tant r ealisation was that
Another initiative centred on re-
architectural design and planning could
imagining how public space could be used
and should be done in collaboration
was inaugurated to celebrate the legacy
(Far left): Concrete structure at the JSE.
with the local community, rather than
of former President Nelson Mandela.
(Below): Workers transform spaces with concrete.
33
shaping our collective future.
We are there when you need support
Need help with your concrete? We offer a free advisory service for general concrete queries. Perfect concrete with us.
www.theconcreteinstitute.org.za +27 11 315 0300
PROJECTS 34
FIRST GREEN HOUSING SOLUTION IN PRETORIA CMA producer member Technicrete
the project managers to have hands-on
was selected to supply its Enviro-Wall
exposure to the benefits of the retaining
retaining wall blocks, base blocks and
wall technology in creating multiple ter-
keystone paving for the eco-friendly
races with ease. For over 18 months we
and energy-efficient Greenhill Estate, a
collaborated in order to supply a product
residential estate on top of Waterkloof
with which the engineers and develop-
Hill in Tshwane.
ers were completely satisfied – not only
Greenhill, developed by the Green
in terms of its performance, but also
Housing Company, comprises 39 ex-
in terms of the final appearance of the
clusively designed units. The develop-
retaining wall, which we supplied in the
ment star ted in August 2017 and
required tan colouring.
Technicrete’s Enviro-Wall retaining wall
retaining wall system. Opening or closing
technology was specified by the project
Complex site
the spacing between the blocks enables
consulting engineers. Construction was
“Once the Greenhill Estate entered the
the Enviro-Wall structure configuration
carried out by Piet Bok Construction.
construction phase, it was important
to be altered so that in the open arrange-
“The benefits gained from Enviro-
for me to ensure that the system was
ment, cavities between adjacent blocks
Wall’s technology were par ticularly
installed according to specifications in
can be filled with soil, promoting plant
relevant to the Greenhill project due to
order to maximise its overall effective-
growth. It can also be installed as a solid
each stand being developed at different
ness. To this end, I regularly inspected
engineering structure.
levels, thereby requiring good, sturdy and
the site. Situated at the top of a koppie,
attractive retaining wall installations,
the project has been the most complex
Multi-purpose
with no risk of soil erosion,” says Piet
site I’ve ever seen from a platform per-
“The blocks are suitable for supporting a
Pretorius of Piet Bok Construction.
spective, with almost all of the 39 stands
wide range of embankment heights and
being at completely different levels.
the wall can accommodate both concave
“This required many walls at different
and convex alignments down to a small
Technicrete’s Justin Kretzmar explains:
levels, weaving in all directions and tying
radius of 2m. With the custom-designed
“We worked on the designs of these
into each other as and where required.
Base Block, the angle of the inclination
walls with the engineers on the Greenhill
We opted for a wall design reinforced with
of the wall is easily set out at 700, but
Estate project long before commence-
horizontal structural geogrids and to this
can be varied if site conditions require
ment of bulk earthworks to show how
end, the Enviro-Wall block – due to its
something different,” says Kretzmar.
the Enviro-Wall technology offered the
shape and interlocking pattern – offers
He adds that Technicrete’s Keystone
best retaining wall solution to this multi-
the best ‘key’ to secure the geogrids
paving was utilised for all the estate’s
levelled project. Wall heights ranged from
from pull-out.
main roads. The pavers combine two dis-
Close collaboration
1-6m, requiring a single design philosophy
“This is possible due to the wall, which
tinctive shapes into one unit, making it an
that could be used across the board,
is constructed from dry stacked inter-
attractive option for driveways, parking
keeping it simple while still remaining
locking, precast blocks. The simplicity of
areas and access roads.
cost-effective and within budget.
the blocks’ design enables them to be
“We provided factory samples for
easily and quickly laid to form an effective
(Top and above): A retaining wall under construction at Greenhill Estate in Tshwane.
PRECAST | ISSUE ONE | 2019
A little bit of magic is to be found just
been applied throughout the estate. The
outside Polokwane in the form of The
DZZs from Technicrete have given The
Aloes Lifestyle Estate, which – since its
Aloes a very upmarket and aestheti-
inception nine years ago – has continued
cally pleasing, yet practical finish. We
to expand its upmarket residential and
utilised Rocla’s [a CMA poducer member]
retirement living concept. The tranquil and
stormwater pipes and sewer manholes
exclusively designed estate contracted
during the Phase One and Phase Three
CMA producer members Technicrete and
expansions for water run-off from the
Rocla for its paving, kerbs, pipes, culverts
roads into kerb inlets.”
and manhole requirements. “The entire Aloes Lifestyle Estate
(Above): Extensive paving inside The Aloes residential and retirement living concept.
Stormwater management
project, from Phase One in 2010 to
“Our manhole components at The Aloes
Phase Five in 2018, has chosen and
have been utilised f or stormwater
installed Technicrete paving and kerbs.
applications at the estate, but are also
Good quality, longevity and affordability
used in sewer applications,” says Robert
are among the factors which made Tech-
Hill from Rocla.
nicrete a preferred choice of supplier,”
Technicrete’s range of DZZ interlock-
says Leon Labuschagne, site agent for
ing pavers form a hard-wearing surface
Oscon Electrical & Civil Contractors.
overlay which is perfect for application
“Near l y 7 000 ker bs o f v ar ious
in lifestyle estates, as well as for petrol
dimensions and 15 700m 2 of Double
forecourts, municipal parking areas,
Zig-Zag [DZZ] 60mm grey pavers have
commercial developments and heavy-
PROJECTS
PAVING POLOKWANE RESIDENTIAL AREA
35
RPOJECTS
duty industrial areas. The pavers form a herringbone pattern, once installed. Rocla’s precast concrete manhole comprises an interlocking joint profile which makes installation quick and effective. When required, a sealant can be utilised between sections to ensure
36
the chamber remains watertight. The manholes are a maintenance-free, highquality solution. Avoiding theft Compared with cast-iron manhole lids, Rocla’s precast concrete lids offer no
“The tranquil and exclusively designed estate contracted CMA members Technicrete and Rocla for its paving, kerbs, pipes, culverts and manhole requirements.”
The pipes are manufactured in 2,44m and 1,22m, but can be manufactured in special lengths to customer specification. The standard strength classes f or these pipes ar e 50D, 75D and 100D (refer to SABS 677). Special intermediate strengths or heavier loading requirements can be designed and manufactured. These are subject to various material constraints, but can be evaluated by Rocla engineers as required. Form and function “Lifestyle estates such as The Aloes
resale value and are less likely to be re-
depend heavily on the functionality and
moved from site. The manhole sections
appearance of products that are finally
are supplied in lengths of 1 000mm,
installed at such upmarket developments.
500mm and 250mm and are available
The products selected from Technicrete by
in diameters of 750mm, 1 000mm,
Oscon Electrical & Civil Contractors are of
1 250mm, 1 500mm and 1 800mm. Spe-
a high quality and provide a lifespan suited
cial sizes can also be accommodated.
to the traffic requirements of the estate,”
Although Rocla’s stormwater pipe
says Mishack Mdhlululi, Technicrete’s sales
is primarily designed for use in a non-
consultant for the Polokwane region.
watertight pipeline, rubber collars can be
“A combination of mountable and semi-
supplied to facilitate a measure of water-
mountable precast kerbs was selected
tightness. These can be used in instances
which gave a superior edge restraint
where ingress of groundwater needs to
finish. We were delighted to have been
be avoided, making the more expensive rubber ring joint pipe unnecessary.
(Above): A Rocla manhole installed at The Aloes Lifestyle Estate in Polokwane.
involved in the development and expansion of The Aloes Lifestyle Estate.”
PROJECTS 37
METRORAIL SAFETY WALL BUILT WITH ECHO PANELS Pre-stressed concrete panels supplied
discourage people from tunnelling under
vantages to this type of walling, speed
by the Echo Group (a CMA producer
the wall. This panel rests on two rein-
of construction and cost being major
member) have been used for a safety
forced concrete footings at each end of
considerations.
wall which has been built adjacent to
an installation bay and supports the two
a railway line in Tembisa, Gauteng. The
slabs above it.
“Eight to 10 bays, or 48-60 linear metres, were completed daily (eight hours).
construction of the wall is the first of
The footings measured 1m x 1,8m x
A conventional masonry wall would have
what will probably be several building
400mm (depth) and were cast on 450mm
taken two or three times as long, with
phases which, when completed, will see
re-compacted, cement-stabilised soil.
no advantage gained in strength or
walling erected on both sides of the
The beam sections were delivered to
durability. In fact, because our panels
30km Metrorail link between Tembisa
site with base plates and flanges already
have a compressive strength of 50MPa,
and Germiston.
attached. After being bolted onto the
they’re virtually indestructible,” says
footings, laser levelling was used for
Esterhuizen.
The project is being undertaken on behalf of the Ekurhuleni Metropolitan
vertical alignment.
Byron Haarhoff, managing director
Municipality and PRASA, principally to
of BKH Construction, adds that Echo’s
prevent pedestrians (especially school
panels come with smooth soffits and do
children) from crossing or walking along
not require maintenance. “They also have
the track, endangering life and limb.
a tongue-and-groove jointing system to
Several fatalities have occurred among
ensure that adjoining panels form a tight
children and adults unaware of oncom-
seal. Moreover, Echo cut out 200mm
ing trains.
x 200mm sections at each end of the
The Phase 1 component is 1,8km
anti-trenching panels to ensure a snug
long. It was designed and built by BKH
fit over the steel flanges, which provide
Construction as a sub-contractor to civil
additional support for the steel uprights.
contractor, Pamodia Projects. The design
“Before actual site work commenced,
was approved by Aurecon Consulting
Thereafter the panels were slotted
we worked hand-in-hand with local
Engineers, based on an analysis of the
between the beam sections by truck-
businesses and community members,
area’s prevailing geotechnical conditions.
mounted crane. Each panel was 120mm
apprising them of what the work would
In addition, two pedestrian subways were
thick, as opposed to the I-section chan-
entail and gaining their assistance in the
constructed by Pamodia Projects under
nels, which were 150mm wide. This left
recruitment of local labour. We use local
the section flanked by the wall, using
a gap of 30mm which was filled with non-
community members in all our projects
precast concrete culverts.
shrinking grout. Wooden wedges were
and in this instance, we upskilled locals in
used to hold the panels flush against one
concrete compaction, the drilling of bolt
Simple solution
of the inner sides of the beam sections
holes, bolting, grouting and the type of
The wall was built simply by sandwich-
to facilitate the grouting process. After
steel we were using for the uprights,”
ing three 6m-long panels between two
three days, the grouting had cured suf-
says Haarhoff.
3m-high galvanised steel beam sections.
ficiently for the wedges to be removed
Two of the panels were 120cm wide and
and the remaining gaps caulked.
were positioned above natural ground level, yielding a wall height of 2,4m. The
Compressive strength
third or anti-trenching panel was 600mm
Echo Group marketing director Melinda
wide and was installed below ground to
Esterhuizen says there are several ad-
PRECAST | ISSUE ONE | 2019
(Top, from left): A partially completed section of the wall in which Echo’s smooth soffits and the close-fitting tongue-and-groove jointing are seen to good effect; a completed section of the wall. (Above): Byron Haarhoff (left) with some of the Tembisa residents who assisted with the construction of the wall.
PROJECTS
LOCAL WINE PRODUCERS SWITCH TO CONCRETE FERMENTATION TANKS Several South African wine producers are following a global trend of fermenting wine
38
in concrete tanks. It might surprise some to know that fermentation in concrete actually has a long history in European vineyards and is used across France in the Rhône Valley, Burgundy and Bandol. Accor ding to well-k nown Fr ench wine master, Christophe Baron, “you can’t have a great wine without great mouth feel – and concrete is all about mouth feel”. “Concrete allows for the gradual oxygenation of the wine, similar to oak barrels, but without the purchased flavours of oak barrels,” says James Mantone of Syncline Wine Cellars in Washington State, USA. “This gives
During the 2018/19 wine season, Ikapa
a truer taste of the vineyard without
Concrete contracted CMA producer
oak aromas or sweetness to cover up
member Concrete Units to produce
deficiencies in the fruit.”
approximately 30 of the egg-shaped
(Above): The Concrete Units factory where eggshaped wine tanks await delivery. (Below): A rectangular wine tank nears completion at the Concrete Units factory.
tanks, in addition to some larger, cubeClever design
shaped units. The ovate tanks have a
On the local front, the development of the
1 520l capacity, while the rectangular
concrete wine tank has been conceptu-
tanks come in four sizes: 2 550l, 6 000l,
alised and pioneered by Ikapa Concrete.
8 000l and 10 000l. Moreover, Concrete
The company’s owner, Dougie Atter-
Units has also made Ikapa’s Petite, an
bury, says that after many years of using
egg-shaped tank, which – as its name
large, epoxy-coated concrete wine tanks,
suggests – is the baby of the bunch, with
new advances in concrete technology
a capacity of only 36l.
have heralded the launch of an uncoated, egg-shaped range of tanks which not only
Egg tanks
finding favour with concrete wine tanks,
breathe, but enhance the quality of the
Concrete Units manager Brian Cook says
including Eikendal Wines, Elgin Ridge Wine
final product.
the manufacture of concrete wine tanks
Estate, Joostenberg Wines, Laibach
required very specific concrete mixes.
Wines, Zevenwacht Wine Estate, Steen-
“Besides precise mix quantities, the
berg Wines and Waterkloof Wine Estate.
water had to be chlorine-free and the
Af ter the wine production period
epoxy, which was used to attach various
from December to February ended,
stainless steel components to the tank,
Ikapa commissioned Concrete Units to
had to be food grade. We used fibreglass
manufacture concrete water storage
moulds and fibre-reinforced concrete
and conservancy (sewerage) tanks during
for the egg tanks and this required
the course of 2019.
maintaining a fine balance between slump
“Some local governments in the
and vibration. We also used a high-quality
Western Cape don’t permit underground
aggregate which took the form of washed
plastic water and conservancy tanks due
granite, sourced in Malmesbury, some
to the fact that they’re prone to rise out
considerable distance from our factory.
of the ground in areas with high and rising
“Casting the egg tanks in fibreglass
water tables. Overstrand, which includes
moulds was very challenging and we had
Hermanus, Betty’s Bay, Kleinmond and
to work very hard to achieve smooth,
Gansbaai, is one such area. Moreover,
blowhole-free finishes,” says Cook.
rising groundwater has seen plastic tanks ‘popping’ in Stellenbosch and
(Above): The 36l Petite.
Growing trend
they’ve been replaced with concrete
Numerous South African producers are
tanks,” says Cook.
PRECAST | ISSUE ONE | 2019
CAST-STONE PAVERS SELECTED
FOR CAPE HOUSING
Kent cobble and Ravine pavers have been used for the paving of driveways and pathways at Sunningdale, a Garden Cities middle-income housing project adjacent to the recently completed Tableview Mall on Cape Town’s Western Seaboard. The cast-stone pavers were produced by
Stuttaford. The inspiration for Garden
CMA producer member Revelstone, which
Cities came from the revolutionary Brit-
also supplied its Ravine pavers for paths
ish Garden City movement started by
and patios in the residential precinct. In
Ebenezer Howard, whose objective was
addition, Revelstone has supplied another
to build entire new towns and improve
Garden Cities development, Pinehurst in
the poor living conditions in parts of
Durbanville, with Kent cobbles and Ravine
Britain during the late 19th and early
pavers for similar applications.
20th centuries.
Founded in 1919, Garden Cities is a
Revelstone has been producing cus-
non-profit organisation which develops
tomised cast-stone products since 1993
entire suburbs. The company says its
for both the domestic and commercial
main purpose is “to provide better
markets. Family-owned, the company
housing and social conditions for the
uses traditional masonry skills combined
people, the latter to be construed in its
with modern moulding techniques to pain-
widest sense”.
stakingly produce master moulds from
In addition to constructing high-quality
original stone. This hands-on approach
houses and public buildings, Garden
allows the creation of custom-made
Cities fosters equality in education by
products, enabling Revelstone to supply
providing school halls to redress decades
pavers and cladding uniquely tailored to
of disadvantage.
its clients’ specific requirements.
The current chairman, Sean Stuttaford, is the great-grandson of the founder, Cape Town businessman, Richard
PRECAST | ISSUE ONE | 2019
(Above): Revelstone’s Ravine pavers (pathway) and Kent cobble (driveway) make for an attractive combination at Sunningdale.
PROJECTS 40
THE JBCC ON DEALING WITH CONFLICTS OF INTEREST IN SITE CLAIMS Disputes and consequent claims on building sites are nothing new and resolving such situations invariably calls for time, patience and skills. But the problem is sometimes exacerbated when a conflict of interest unexpectedly crops ups, says Uwe Putlitz, CEO of the Joint Building Contracts Committee (JBCC).
with a claim from the contractor for
with execution criteria within stipulated
additional costs and/or an extended con-
time periods and along agreed proce-
struction period – and then finds that the
dures must be followed,” he adds.
cause for the claim is non-performance or
Putlitz adds that because the causes
incompetence by an individual employed
of conflict on building sites are so var-
by his very own firm. “It could actually be
ied, it is essential that the client at the
far worse: not only could the culprit be
outset determines an effective com-
working for the same firm of consultants,
munication strategy involving all project
but he or she could even be the principal
participants throughout the design and
agent or the project manager.”
construction phases, together with the
Putlitz says that in such cases, only
delegated levels of authority of team
two solutions are available:
members. “This procedure would simplify
• The principal agent must immediately
the avenues to follow when disputes of
notify his or her company’s profes-
any type arise,” he advises.
sional indemnity insurer and then,
collectively, the client as well to make
a fair determination of the claim in
consultation with the insurer – and
accept responsibility for the costs
thereof; or
• Appoint another agent to deal with the claim in question – and immediately notify his or her professional indem-
The JBCC is a non-profit company which
nity insurer to resolve the degree of
represents building-owners and develop-
liability and costs thereof.
ers, professional consultants, and gen-
“Sweeping the issue under the pro-
eral and specialist contractors who all
verbial carpet definitely isn’t a solution.
provide input for the compilation of JBCC
A n unknown writer once obser ved:
agreements (contracts) that portray
‘Contracts are there to allocate blame.’
the consensus view of the committee’s
Indeed, standard forms of construction
constituent members.
contract have been drafted to be ‘just’
Putlitz says difficulties may arise
and ‘fair’ to both parties – but to achieve
(Top): The JBCC building site.
when a project’s team leader must deal
this, the provisions of the clauses dealing
(Above): Uwe Putlitz, CEO of the JBCC.
PRECAST | ISSUE ONE | 2019
DRONES MAY BE THE ANSWER TO RESOLVING DISPUTES Drones hovering over and transmitting photos from building sites could in future play an important role in resolving disputes in construction contracts, says Uwe Putlitz, CEO of the Joint Building Contracts Committee (JBCC). T he JBC C is a non-pr o f it company
safely used in the location of a project,
which represents building-owners and
according to legal stipulations – can show
developers, professional consultants,
“hidden” aspects of the works by flying
and general and specialist contractors
over relatively inaccessible areas on site.
who all provide input for the compilation
The drones can even inspect adjacent
of JBCC agreements (contracts) that
properties to ensure that no building
por tray the consensus view of the
materials have accidentally been dropped
committee’s constituent members.
on them from cranes. “Dispute resolution
Putlitz says the advent of digital
almost inevitably involves prolonged post-
photography and incorporation of cameras
incident meetings, with unproven claims
in mobile phones in the past decade have
delaying finalisation. Now, with drones in
already helped tremendously to show
attendance, parties involved could table
progress or identify potential problems
photographic evidence from an ‘eye in
on building sites. “The new smartphones
the sky’. Drones open up totally new
have enabled parties involved with a
dimensions to validate claims.
building contract to obtain instant
“In addi tion to a dr one’s abili t y
photo or video recordings, incorporating
to measure building progress or
the date and time – essential information
spot defective work, the auto-pilot
in dealing with disputes. But hand-
systems could help health and safety
held or fixed cameras – however
officers timeously identify unsafe work
strategically positioned – can show only
procedures – an urgently needed tool
a pre-selected portion of a project and
to improve safety on site, which has
their use is also open to manipulation. The
already reached alarming low levels in
development of remotely piloted aircraft
SA,” Putlitz adds.
systems – so-called drones – has totally removed all these limitations.” Putlitz says drones – provided they’re
PRECAST | ISSUE ONE | 2019
(Below): The JBCC predicts that drones taking aerial photos of building sites could in future provide proof to speed up the resolution of many disputes.
PROJECTS 42
LOCAL MOULD MANUFACTURER
CRAFTS WINNING FORMULA Precast concrete mould producer Nigel Brown Moulds (NBM) is a success story which deserves to be heard, especially by aspirant entrepreneurs. NBM supplies thousands of moulds to 45 African countries annually. It also has customers as far afield as
We also do a lot of Vibracrete moulds.
If visiting customers are not convinced as
the UK and Australia. Fifty percent of
“Our fibreglass moulds generally
to the strength of these moulds, Brown
the company’s output is exported, while
last around five years, but the beauty
twists a 10-year-old rubber mould inside
the rest is supplied on the local market,
of fibreglass is that if it’s chipped or
out, stands on it and then smashes it
of which 90% is sold in Gauteng. NBM
damaged, it can easily be repaired. Our
with a hammer. When customers see
works in fibreglass, polyurethane (rubber)
customers are more than happy to repair
that no harm has been done to the mould,
and steel. Steel moulds were introduced
their own moulds. All it requires is some
they invariably buy the product.
in April 2018.
grinding, filler material and then sanding,
“We used to sub-contract orders for
and within half an hour, the repair’s done.”
steel moulds, but last year I invested
Founder and managing director Nigel Brown says he first began producing
in an imported steel CNC guillotine and
moulds for concrete products in Port
Durable solution
Elizabeth (PE) 18 years ago.
NBM’s rubber moulds, which are mainly used for the production of flagstone
Filling a gap
pavers, are extremely durable and are
“At the time, I was working for a nursery
generally good for 10 years’ production.
(Top, from left): Maltreating a rubber mould to demonstrate its durability and longevity; steel moulds to be used for kerb production. (Below): Nigel Brown Moulds’ recently-imported steel CNC guillotine and bending brake machine.
and our customers made r epeated requests for concrete products we didn’t stock. So I decided to make them myself. Initially I outsourced the moulds, but I soon realised that if I produced them myself, I’d make a better product. I then started selling the moulds and it wasn’t long before I became a specialist mould producer. I sold the PE business in 2001 and moved to George, where I founded Nigel Brown Moulds,” says Brown. “Fibreglass moulds produced by NBM are used for a diverse range of products, including concrete balls for driveways, building columns, flower pots, bird baths, benches, edging and other applications.
PRECAST | ISSUE ONE | 2019
give us the accuracy to produce identical m o u l d s f o r r e p e a t o r d e r s . We’r e currently making thousands of moulds for kerbs and are also producing moulds for retaining wall blocks. “In addition, last year we started manufacturing small vibration tables and concrete mixers branded as Outeniqua
“I spent the last week of November 2018 in Malawi after the client ordered a truckload of moulds.”
Rust Concrete Machinery. This required
“Part of the service we provide is free
us to expand into new factory premises.
training. For example, I spent the last
Our philosophy is to keep the weight of
week of November 2018 in Malawi after
our tables, which use electric motors
the client had visited us in George and
imported from Italy, down to no more
had ordered a truckload of moulds. His
than 110kg so that they can be lifted
company makes hundreds and thousands
by five men,” explains Brown.
of bricks and blocks each day and he
PROJECTS
bending brake machine. These machines
43
wanted to start producing flower pots, Global venture
tables and benches, bird baths, etc.
“Most of our exporting is done via road
“I trained 10 people in that company
freight, with only a small portion going
in mixing the concrete for those ap-
by sea. Moulds are big and bulky, which
plications and lubricating the moulds.
“Our business in Africa doubled during
makes air freight very costly. We’ve
I showed them everything and when I
2018 and one of our first orders for 2019
found that the further north we go, the
left, they were producing a range of
was for 50 moulds which were sent to
greater the competition from European
concrete products. While I was there,
Brazzaville in the Republic of the Congo,”
companies. This is because north of
we also damaged a fibreglass mould on
says Brown.
the Equator, their transport costs are
purpose so I could show them how to do
cheaper than ours.
the repair work.
(Above): Nigel Brown and some of his fibreglass concrete moulds prior to shipping.
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MEMBER LIST 44
PRODUCER MEMBERS A FICK SEMENT WERKE BK TEL: (022) 913 1921 PROVINCE/COUNTRY: WC PILLAR: PB AVENG INFRASET (PTY) LTD TEL: (011) 876 5500/872 1713 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI
ECHO FLOORS (PTY) LTD TEL: (011) 668 1900 PROVINCE/COUNTRY: GAUT ECHO PRESTRESS DURBAN (PTY) LTD TEL: (032) 947 3067 PROVINCE/COUNTRY: KZN HORIZON BRICK & CONCRETE TEL: (012) 943 3701 PROVINCE/COUNTRY: N/W PILLAR: PB
BANZI TRADE 31 (PTY) LTD T/A BRICKIT TEL: (011) 023 6708 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI
LATEGAN CEMENT WORKS (PTY) LTD TEL: (021) 873 1154 PROVINCE/COUNTRY: WC PILLAR: PB/PI
BETA TILES (PVT LTD TEL: (263) 4333735 PROVINCE/COUNTRY: ZIM PILLAR: PB
MARLEY ROOFING (PTY) LTD TEL: (011) 316 2121 PROVINCE/COUNTRY: GAUT PILLAR: PB
BOSUN BRICK BRITS (PTY) LTD TEL: (012) 250 1711 PROVINCE/COUNTRY: NW
MOBICAST (PTY) LTD TEL: 086 111 2346 PROVINCE/COUNTRY: WC PILLAR: PB/PI
BOSUN BRICK MIDRAND (PTY) LTD TEL: (011) 310 1176 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI BOSUN BRICK PORT ELIZABETH (PTY) LTD TEL: (041) 405 0100 PROVINCE/COUNTRY: EC C.E.L. PAVING PRODUCTS (PTY) LTD TEL: (021) 905 5998 PROVINCE/COUNTRY: WC PILLAR: PI CEMBLOCKS (PTY) LTD TEL: (014) 538 0311 PROVINCE/COUNTRY: NW PILLAR: PB/PI CEM BRICK MANUFACTURERS (PTY) LTD TEL: (051) 433 4479 PROVINCE/COUNTRY: F/STATE PILLAR: PB/PI CIVILWORKS (PTY) LTD REAL TIME INVESTMENTS TEL: (011) 903 7023 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI CONCRETE UNITS (PTY) LTD TEL: (021) 386 1923/ (016) 362 2236 PROVINCE/COUNTRY: WC/GAUT PILLAR: PB/PI CONFRAMAT (PTY) LTD TEL: (0861) 33 5599 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI
MONIER COVERLAND (PTY) LTD TEL: (011) 222 7300/7334 PROVINCE/COUNTRY: GAUT PILLAR: PB MVA BRICKS CC TEL: (012) 386 0050 PROVINCE/COUNTRY: GAUT PILLAR: PI PANDA (PTY) LTD TEL: (00267) 244 2107/8 PROVINCE/COUNTRY: BOTS PILLAR: PB/PI PORTLAND HOLLOWCORE SLABS (PTY) LTD TEL: (021) 972 1111 PROVINCE/COUNTRY: WC PILLAR: PI REMACON PRODUCTS CC TEL: (011) 393 5504 PROVINCE/COUNTRY: GAUT PILLAR: PI REVELSTONE (CAPE) (PTY) LTD TEL: (0861) 173 835/(021) 761 9737 PROVINCE/COUNTRY WC PILLAR: PI ROCLA (PTY) LTD TEL: (011) 670 7600 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI SHUKUMA BRICKS (PTY) LTD TEL: (041) 372 1013 PROVINCE/COUNTRY: EC PILLAR: PB
VANSTONE PRECAST (PTY) LTD TEL: (012) 541 2056/1808 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI VIBRO BRICKS AND PAVING (PTY) LTD TEL: (012) 374 5533 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI WEST END CEMENT BRICKS (PTY) LTD TEL: (011) 851 1005 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI NON-PRODUCER MEMBERS ABEL EQUIPMENT CC TEL: (044) 874 1876 PROVINCE/COUNTRY: EC BASF CONSTRUCTION CHEMICALS SOUTH AFRICA (PT Y) LTD TEL: (011) 203 2400 PROVINCE/COUNTRY: GAUT BIRKENMAYER H (PT Y) LTD TEL: (011) 970 3880 PROVINCE/COUNTRY: GAUT CHRYSO SOUTHERN AFRICA (PT Y) LTD TEL: (011) 395 9700/ (031) 564 0325/(021) 928 1660 PROVINCE/COUNTRY: GAUT/ KZN/ WC DICK KING LAB SUPPLIES (PT Y) LTD TEL: (011) 499 9400/ (031) 700 2551 PROVINCE/COUNTRY: GAUT/DBN FIBERTEX SOUTH AFRICA (PT Y) LTD TEL: (031) 736 7100 PROVINCE/COUNTRY: KZN HAWKEYEPEDERSHAAB TEL: 00 459645 4193 PROVINCE/COUNTRY: DENMARK KERNEOS SOUTH AFRICA (PT Y) LTD TEL: (011) 444 3090 PROVINCE/COUNTRY: GAUT KOBRA MOULDS B.V. TEL: 003111 356 2460 PROVINCE/COUNTRY: NETHERLANDS MANITOU SA (PT Y) LTD TEL: (011) 975 7770 PROVINCE/COUNTRY: JHB PAN MIXERS SA (PT Y) LTD TEL: (011) 578 8700/8600 PROVINCE/COUNTRY: JHB QUANGONG MACHINES CO LTD TEL: +865 958 679 9557 PROVINCE/COUNTRY: CHINA SIKA SOUTH AFRICA (PT Y) LTD TEL: (031) 792 6500 PROVINCE/COUNTRY: KZN
CORESLAB (PTY) LTD TEL: (087) 232 2462 PROVINCE/COUNTRY: LIMPOPO PILLAR: PB/PI
SHUKUMA FLOORING SYSTEMS T/A ZITTLAU EIENDOMME (PTY) LTD TEL: (041) 372 1933 PROVINCE/COUNTRY: EC PILLAR: PB
COROBRIK (PTY) LTD TEL: (031) 560 3252 PROVINCE/COUNTRY: KZN PILLAR: PI
SILVERTON PRECAST (PTY) LTD TEL: (012) 804 4525 PROVINCE/COUNTRY: GAUT PILLAR: PI
DERANCO PRECAST (PTY) LTD TEL: (041) 463 3338 PROVINCE/COUNTRY: EC PILLAR: PB/PI
SMARTSTONE (PTY) LTD TEL: (011) 310 1161 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI
EAGLE ROOF TILES (PTY) LTD TEL: (044) 874 0290 PROVINCE/COUNTRY: WC PILLAR: PB
TECHNICRETE (PTY) LTD TEL: (011) 672 1425/670 7600 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI
ASPASA TEL: (011) 791 3327 PROVINCE/COUNTRY: JHB
ECHO PRESTRESS (PTY) LTD TEL: (011) 589 8800/8899 PROVINCE/COUNTRY: GAUT PILLAR: PB
TOPFLOOR CONCRETE (PTY) LTD TEL: (021) 951 7700 PROVINCE/COUNTRY: WC PILLAR: PB
BRITISH PRECAST CONCRETE FEDERATION TEL: +(44) 116 232 5170 PROVINCE/COUNTRY: UK
TECHMATIK S.A. TEL: (0048) 608 422 300 PROVINCE/COUNTRY: POLAND TERRAFORCE (PT Y) LTD TEL: (021) 465 1907 PROVINCE/COUNTRY: WC
CIVILPRO ENGINEERING SOLUTIONS (PT Y) LTD PROVINCE/COUNTRY: JHB CONCRETE SOCIET Y OF SOUTHERN AFRICA TEL: (012) 348 5305 PROVINCE/COUNTRY: PTA CPI CONCRETE PLANT INTERNATIONAL TEL: (02236) 962390 PROVINCE/COUNTRY: GERMANY ILIFA AFRICA ENGINEERS (PT Y) LTD TEL: (012) 941 1616 PROVINCE/COUNTRY: PTA JC PAVING CONSULTING TEL: (011) 431 0727 PROVINCE/COUNTRY: JHB SARMA TEL: (011) 315 0300 PROVINCE/COUNTRY: JHB SEKHUKHUNE & ASSOCIATES TEL: (012) 346 1945 PROVINCE/COUNTRY: PTA TACO VOOGT CONSULTING ENGINEER TEL: (012) 669 0125 PROVINCE/COUNTRY: PTA YOUNG & SATHARIA CONSULTING CIVIL ENGINEERS TEL: (031) 207 7252 PROVINCE/COUNTRY: KZN CONTRACTOR MEMBERS BUFFALO RETAINING WALLS CC TEL: (016) 366 1801 PROVINCE/COUNTRY: GAUT DECORTON RETAINING SYSTEMS (PT Y) LTD TEL: (021) 875 5155 PROVINCE/COUNTRY: WC FRICTION RETAINING STRUCTURES (PT Y) LTD TEL: (011) 608 4321 PROVINCE/COUNTRY: GAUT POWERGATE CONSTRUCTION CC TEL: 071 603 5070 PROVINCE/COUNTRY: GAUT VALCAL INTERNATIONAL EXPORT CC TEL: (011) 867 2471 PROVINCE/COUNTRY: GAUT CEMENT MEMBERS AFRISAM SOUTH AFRICA (PT Y) LTD TEL: (011) 670 5500/5752 PROVINCE/COUNTRY: GAUT PPC LTD TEL: (011) 386 9000/909/626 3150 PROVINCE/COUNTRY: GAUT SEPHAKU CEMENT (PT Y) LTD TEL: (012) 684 6300 PROVINCE/COUNTRY: GAUT
ASSOCIATE MEMBERS AF CONSULTING ENGINEERS & ASSOCIATES (PT Y) LTD PROVINCE/COUNTRY: JHB
PI – Precast Infrastructure PB – Precast Building
PLEASE NOTE: The above member list was correct at the time of going to print. If your details have changed, please contact Rita at the CMA offices on tel: (011) 805 6742.
PRECAST | ISSUE ONE | 2019