PRECAST VOLUME Seven ISSUE 3 • 2013
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the cma – QUALITY CAST IN CONCRETE
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• Mammoth culverts for stacker tunnels
iatio
• Precast concrete panels add lustre to green building
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• Blue Route Mall – responsible urban development
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contents
1
precast contents THE CONCRETE INSTITUTE
2
TECHMATIK SETS SIGHTS ON AFRICA
2
LIFETIME ACHIEVEMENT AWARD FOR
GÜNTER KOCH 3 EZETHU LOGISTICS SECURES
AFRISAM DELIVERY CONTRACT
4
MUCH-MALIGNED CONCRETE HAS
EXCELLENT ECOLOGICAL PROFILE 4
TOTALLY CONCRETE expo 2014
4
CMA HOSTS BFT INTERNATIONAL
CHEMICAL ADMIXTURES
27 ECO-TILE® EXTRUSION FOR A BRIGHT
HOUSING FUTURE
27 Greater MOISTURE
MEASUREMENT ACCURACY
PRECAST VOLUME SEVEN ISSUE 3 • 2013
The cement silos (left) and ash silos at Sephaku Cement’s 155 ton-per-hour cement milling plant, currently under construction south west of Delmas in Mpumalanga. The project incorporates the latest environmentally-friendly technology with particular emphasis on high efficiencies and reduced power consumption. Production is scheduled to begin in the early part of 2014.
7
BLUE ROUTE mall PERMEABLE
PAVING PROJECT
a
nu
facturer
s
n
• Mammoth culverts for stacker tunnels
iatio
• Blue Route Mall – responsible urban development
• Precast concrete panels add lustre to green building
ARTICLES
ON THE COVER
THE CMA – QUALITY CAST IN CONCRETE
soc
LAFARGE QUARRY HOSTS KNYSNA RETIREES
26 AFRISAM ADVISES ON
as
5
CONTROL CONTRACT
m
ncrete
2 EXCEPTIONAL SUPPORT FOR
26 ACTOM EXECUTES FAST-TRACK DUST
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NEWS
Q
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cast in conc
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10 PRECAST CONCRETE PANELS ADD LUSTRE
TO WATERFRONT OFFICE DEVELOPMENT
Precast is the official journal of the Concrete Manufacturers Association (CMA)
14 PRECAST CONCRETE PREDOMINATES
16 Horn Street, Chloorkop, Kempton Park, 1620
PostNet Suite 8612, Private Bag X32, Kempton Park, 1620
AT ‘THE WILLIAM’
16 CONCRETE BLOCK PAVING CHOSEN
FOR PIETERMARITZBURG URBAN
RENEWAL PROJECT
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
18 SWAZILAND OPTS FOR PATENTED
PO Box 651793, Benmore, 2010, South Africa
Tel: +27 11 883 4627, Fax: +27 11 883 4627
PRECAST CONCRETE BARRIER SYSTEM
20 MAMMOTH PRECAST CONCRETE
CULVERTS CHOSEN FOR TWeeFONTEIN
STACKER TUNNELS
22 CMA WELCOMES NEW MEMBERS
Website: www.isikhova.co.za Publisher: Andrew Meyer Tel: +27 11 883 4627, Cell 082 456 5175 E-mail: andrewm@isikhova.co.za Editor: David Beer Tel: +27 11 478 0239, Fax: +27 11 678 0254
COVER STORY 12 NEW SEPHAKU PLANT ON TRACK
E-mail: bigsky@ibi.co.za Advertising: Andrea Latham Tel: +27 11 883 4627 E-mail: communications@isikhova.co.za Design, layout and production: Joanne Brook
advertorial 21 pmsa confident of further growth
APPLICATIONS 25 ECHO PRESTRESS builds HIGH
Tel: +27 11 883 4627 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 he, 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.
STRENGH SECURIT Y WALL
PRECAST VOLUME 7 • ISSUE 3 • 2013
2
NEWS
EXCEPTIONAL SUPPORT FOR THE CONCRETE INSTITUTE The exceptionally high level of support
centre, says sales of publications have also
for, and interest in, the operations of The
been running at very high levels.
For more information about the School training programme, contact eldenem@
Concrete Institute has shown how much
“The marketplace seems relieved that
theconcreteinstitute.org.za and for gen-
the construction industry appreciates the
T he Concr ete Institute is continuing
eral inquiries about publications, contact
Institute’s preservation of the services
to sell all the publications previously
info@theconcreteinstitute.org.za, phone
previously rendered by the now defunct
published by the C&CI. When we exhibited
011 315 0300, or visit www.theconcrete-
Cement & Concrete Institute.
at the recent Totally Concrete expo at the
institute.org.za
Managing dir e c t or, Br y an P er r ie,
Sandton Convention Centre, sales of our
says the volume of inquiries calling for
publications were so high that we had to
advice on concrete technology matters
fetch new stock.”
has not abated, student numbers at the
Battison says the support for the Infor-
Institute’s School of Concrete Technology
mation Centre has come from construction
continue to be high, and demand for the
and building industry members at all levels.
services of the Information Centre has
“We’ve provided reference material for the
been a revelation.
research work of students and top academ-
“It’s been back-to-business almost
ics since re-opening on May 2,” she said.
from the day we announced that AfriSam,
The School of Concrete Technology’s
Lafarge and Sephaku had stepped in to fund
2013 Education Programme has just been
the institute,” Perrie stated.
published and the second edition of the
Mar tha de Jager who, with Susan Battison, manages the CI’s information
‘Concrete Projects for the Garden’ is also now available.
The Concrete Institute stand at the Totally Concrete expo in Sandton.
TECHMATIK SETS SIGHTS ON AFRICA September saw CMA member and precast
approach has realised impressive reduc-
concrete machinery specialist, Techmatik
tions in production costs, with savings of
SA, announce its commitment to an African
up to 40% in power consumption and 20%
marketing initiative at bauma Africa 2013,
in cement usage, in comparison to other
the first such exhibition and conference to
leading precast concrete block-making
be held on the continent.
machinery manufacturers.
This highly successful Polish company
“We have installed over 40 plants in
has been manufacturing plant for the
Europe and Asia since 2007 alone and we
production of various types of vibro-
believe that the potential for our concrete
pressed interlocking paving blocks, kerbs,
casting machinery in Africa is huge.
watercourses, bricks, blocks and other
Techmatik international sales manager, Marcin Nowakowski (left), and sales and marketing specialist, Magdalena Piliszek, seen here with CMA executive director, Wally Armstrong at the Techmatik stand at bauma Africa 2013.
others, this extremely efficient plant is
“Our African breakthrough came this
the largest of its kind in North Africa and
year when we installed a plant in Tripoli,
we anticipate the installation of several
International sales manager, Marcin
Libya. Producing several products including
similar-sized plants in southern Africa,”
Nowakowski, says the company’s innovative
paver s, masonr y blocks, kerbing and
says Nowakowski.
concrete products, since 1989.
Lifetime achievement award presented to GÜnter Koch Long-standing masonry consultant, Günter Koch,
Housing Foundation. T he award recognised
has been presented with a Lifetime Achievement
Koch’s 45 years of passion, vision and pro-
Award by the Minister of Human Settlements,
fessionalism in the promotion of housing built
Provincial Government of the Western Cape, Mr
with cement and concrete products, and his
Bonginkosi Madikizela.
tireless engagement with all sectors of the
The presentation took place on 17 September at an annual gathering of the Southern African
PRECAST VOLUME 7 • ISSUE 3 • 2013
housing industry in striving for the provision of quality affordable housing.
Günter Koch.
NEWS
3
Ezethu Logistics secures AfriSam delivery contract Ezethu Logistics, the empowerment partner of JSE-listed supply chain specialists Cargo Carriers, has been awarded the contract to transport cement from AfriSam’s Ulco operation near Kimberley to the company’s readymix facilities in the Western Cape. Ezethu Logistics has dedicated eight powder tankers to the contract, which will deliver bulk cement to plants in Bellville, Cape Town City and Philippi. Andre Jansen van Vuuren, Cargo Carriers divisional director of marketing, believes three factors gave Ezethu Logistics the edge: a reputation for reliable, cost-effective supply chain logistics in fuels, chemicals and powders; certified compliance with the best safety, health, environment and quality (SHEQ) standards; and a B-BBEE compliance rating of Level 2. Service providers’ B-BBEE ratings are an important factor in the awarding of contracts by AfriSam. Ezethu’s Level 2 rating allows AfriSam to claim more than 100% compliance in terms of its procurement charter. This rating, complemented by Ezethu’s competitive pricing, played a significant role in the company securing the contract. Since 2003, Cargo Carriers and Ezethu Logistics have pioneered the concept of owner-drivers, providing training and support to allow drivers to become stakeholders in the industry. The result is genuine empowerment, backed by Cargo Carriers’ financial muscle, stringent health and safety standards and a 57-year old reputation for business reliability. Six of the eight tankers are driver-owned and each vehicle will cover 21 500km per month. Computerized logistics and vehicle tracking facilitate strict shift times and reduced delivery costs without compromising reliability or driver safety. “We’re really ‘sweating the assets’,” says Jansen van Vuuren. “We stay strictly within industry standards for driving times and shift times, but our logistics give us the edge in turnaround times and load monitoring”. Ezethu’s growth in the fuels, chemicals and powders sector is testimony to the company’s attention to SHEQ standards, as demonstrated by its ISO 14001, OHSAS 18001 and ISO 9001 certification.
Two Cargo Carriers tankers which will transport bulk cement for AfriSam.
PRECAST VOLUME 7 • ISSUE 3 • 2013
4
NEWS
MUCH-MALIGNED CONCRETE HAS EXCELLENT ECOLOGICAL PROFILE Concrete and cement are often unfairly
use of extenders such as blast furnace
“Concrete has an excellent ecological
blamed for unacceptably high carbon-
slag, fly ash, limestone and other similar
profile compared to other construction
dioxide emissions, comments Bryan Perrie,
materials which would end up in landfills
materials and its social contribution cannot
MD of The Concrete Institute.
if not used by the cement and concrete
be overestimated. It is the second most
Perrie says the current average world-
industry. Another industry contribution
used resource in the world after water, and
wide consumption of concrete is about
towards sustainability is the sourcing
contributes significantly to our standard
a ton per year for every living person.
of synthetic gypsum from industrial by-
of living.
“Notwithstanding this extensive use, the
products from the fertiliser and sulphuric
global cement industry still accounts for
acid industries.”
Perrie believes using concrete makes environmental sense because properties
only about 5% of man-made carbon-dioxide
Perrie says when selecting aggregates
such as economy, thermal mass, fire
emissions. Approximately 40% of this
for sustainable concrete production, it
resistance and water-tightness all add
comes from burning coal and 60% from the
is important not to choose the cheapest
to the sustainability of concrete in the
calcination of limestone. It should also be
sand as this may result in more expensive
built environment. “Concrete structures
remembered that structures are not con-
concrete with a significantly higher carbon-
have optimal energy performance with
structed out of cement but from concrete
dioxide footprint. The use of recycled
associated positive effects on whole-life
- of which cement is but one ingredient.”
concrete as an aggregate will further
energy usage,” he concludes.
T he aver age international level o f
reduce the carbon-dioxide emissions of
carbon-dioxide emissions is about 1 000kg
concrete while simultaneously preserving
per ton of pure cement.
natural resources and eliminating the need
“This value is being reduced by new
for dumping old concrete at landfill sites.
technology and the use of alternative
“Although the proportion of admixtures
fuels in cement kilns, including the burning
in a concrete mix is relatively small, recent
of waste tyres. The primary method of
developments in admixture technology mean
significantly reducing the emissions is to
that admixtures can have a major positive
lower the clinker factor in cement by the
effect on sustainability,” he explains.
Sustainable and striking structures can be achieved with concrete, the second-most used resource in the world.
TOTALLY CONCRETE EXPO 2014 Totally Concrete Expo 2014 will run from
ated with the concrete and construction
economic factors and the global trends
26-28 May at the Sandton Convention
industries. Green initiatives, the entry of
which influence Africa’s construction
Centre in Johannesburg. Totally Concrete is
new and foreign cement manufacturers,
industry will also be highlighted, as will
Africa’s definitive educational and network-
internationalisation, and the significant new
some tools and solutions which assist
ing platform for insights into the latest
opportunities of fered by cross-border
the management of large infrastructural
developments and technologies associ-
deals are on the agenda for 2014. Macro-
projects. View www.totallyconcrete.co.za.
CMA HOSTS BFT INTERNATIONAL BF T IN T E RN AT ION A L e di t or -in - chie f
covered manufacturers of concrete and
Christian Jahn (centre), in discussion with
precast concrete products in addition
CMA executive director, Wally Armstrong
to companies which specialise in precast
(right), and Silvio Ferarris, CEO of ReMaCon
construction. Aimed at construction-
Products. Jahn’s mid-September visit
industry executives and distributed world-
coincided with bauma AFRICA 2013, and
wide, this highly regarded publication forges
besides representing BFT INTERNATIONAL
a link between building materials machinery/
at the exhibition, he also visited some of
suppliers and precast plants, and provides
the CMA’s producer member companies.
a platform for the international exchange
BFT INTERNATIONAL is a trade journal which, for more than seven decades, has
PRECAST VOLUME 7 • ISSUE 3 • 2013
of scientific discoveries and innovative concrete-related technology.
NEWS
5
Lafarge’s Witfontein Quarry hosts Knysna retirees Lafarge South Africa’s Witfontein Quarry
construction of housing that is more
hosted a group of visitors from the Knysna
compact, durable and beautiful, in cities
branch of the University of the Third
that are better connected by road, rail
Age (U3A) on 23 August. U3A is an active
and air. This same expertise will also
group of retirees which has been running
improve the development of rural towns
a series of monthly geology lectures
and villages.
in conjunction with f ield excur sions.
An early Arbour Day celebration was
Witfontein Quarry is of particular geo-
combined with the U3A visit and involved
logical interest and the visitors were keen
the plan ting o f indigenous tr e e s a t
to examine its rock formations.
the quarry entrance. In addition, as a
L a f ar ge South A f rica is the local
donation towards the local Graaff-Reinet
subsidiary of the international Lafarge
and Districts Cancer Association’s ‘Pink
Group, a world leader in building materials
Trees for Pauline’ initiative, the Quarry
and an industry leader in sustainable
purchased 50 metres of pink fabric to
development. All of the Group’s quarries
wrap around the trees.
have active rehabilitation and biodiversity
“We were delighted to give something
conser vation programmes. It was
back to the senior members of our lo-
explained to the visitors how the quarry
cal community,” says Lafarge’s Stewart
p la y s a k e y r o l e in L a f ar g e’s gl ob al
Chislett, Witfontein Quarry Manager. “The
drive to provide solutions for Building
enthusiastic interest of the visitors con-
Better Cities, solutions that help the
tributed to an enjoyable day for everyone.”
Lafarge’s Witfontein Quarry, where Knysna’s U3A branch assisted wrapping trees in pink fabric to support the local CANSA ‘Pink Trees for Pauline’ initiative.
ARTICLE
7
BLUE ROUTE mall – a green guide for responsible urban development South Africa’s largest sustainable urban drainage system (SUDS) and permeable paving project to date was completed in August at Blue Route Mall, a new shopping centre in Tokai, Cape Town. Spanning some 45 000m² of combined parking and drainage area, the development complies with the City’s Management of Urban Stormwater Impacts Policy which aims to reduce the negative impact of impermeable surfaces on aquatic eco systems. These measures are referred to in the Policy
but upsets the delicate balance of aquatic
as Best Management Practices (BMPs)
eco systems in natural water courses
and they fall into two groups, structural
such as rivers, streams and vleis, and
controls and non-structural controls.
unless remedial action is taken to reverse
The top layer of Inbitex® sheeting is laid at Blue Route Mall.
According to Martin Thompson, Cape
this process, the absorption, attenuation
Town’s head of Stormwater Catchment
and quality improvement associated with
Planning (South Peninsula), the primary
natural run-off are lost. Permeable paving
reason for the deterioration of urban water
is one of the structural controls we employ
is the disruption of the natural water cycle.
to maintain or mimic these natural flow
“Over the past decade Cape Town has
systems and prevent the wash-of f of
12- 18 month environmental analysis and
experienced unprecedented development
urban pollutants into receiving waters,”
Blue Route’s developers, Fountainhead
both in greenfield areas and in existing
says Thompson.
Trust, were not able to wait that long.
Some of the completed paved surfaces at Blue Route Mall which clearly show the voids between the pavers.
developed/ brownfield areas. Urban
Other structural controls such as green
In the end permeable paving proved the
surfaces, such as roads, pavements, parking
roofs, sand filters, swales, soak-aways
most cost-effective option, in achieving a
lots and roofing have been traditionally
and retention ponds could have been used
functional sustainable stormwater system.
impermeable and these surfaces increase
to treat water-borne pollutants and to
“One o f the gr e a t ad v an t age s o f
the volume of stormwater run-off and the
control egress into the city’s stormwater
permeable paving is that it uses the
accumulation of pollutants in rain water.
drainage system at Blue Route Mall.
same space as open parking areas, unlike
Impermeable surfaces also increase the
According to sustainable stormwater
swales and attenuation ponds which
systems consultant, Peter Wium, swales
require a dedicated single-purpose space.
“Increasing urbanisation not only places
were considered as an alternative solution
And besides controlling water flows into
pressure on existing stormwater drainage
but this option would have required a
stormwater drainage and rivers, in this
likelihood of flooding during heavy rainfall.
PRECAST VOLUME 7 • ISSUE 3 • 2013
8
ARTICLE
case the Keysers River north of the Mall,
Formpave Aquaflow Permeable Paving SUDS
indents so that when they are laid, voids
permeable paving reservoirs also remove
system which has been used successfully
of ±8mm are created between the pavers.
pollutants from the water,” says Wium.
for the past 20 years and is officially
These gaps allow large volumes of water
A full geotechnical investigation was
recognised by the City of Cape Town. The
to infiltrate into the permeable paving res-
under taken by consulting engineer s,
City Council insisted that the permeable
ervoir. This means that even during heavy
Aurecon, to determine the permeability of
paving surface be designed with low spots
downpours there is no puddle formation.
the soil and which permeable paving option
so that if water ponding occurred in these
Blue Route Mall’s permeable paving res-
would be the most suitable. It entailed
areas it would indicate clogged joints which
ervoir was designed to have an absorption
measuring the level of the water table -
needed cleaning. Moreover, part of the
of 4 500mm per square metre per hour
which should be at least 400mm below
Council’s SUDS policy requirement was an
after 10 years, however, the rate was
the lowest stone layer for a successful
80% reduction of suspended solids and a
double that immediately after installation.
permeable paving installation - as well
45% reduction of total phosphorus. The
as establishing the ratio of permeable to
Aquaflow system easily achieves this.
The paving blocks were manufactured locally under license to Formpave which
impermeable surfaces. In the end a ratio
“This is where the Formpave permeable
of 2.5 non-permeable surfaces to one
paving system is very reliable as its water
permeable surface was adopted.
purifying attributes are well established. It
The paver used at Blue Route Mall is
A s an ticip a t e d, a dual sy st em o f
is not only tried and tested in the United
the Aquaflow 200 x 100 x 80 standard
infiltration and egress proved to be the
Kingdom, but has been used successfully
rectangular concrete block in two colours.
most viable permeable paving solution for
on all 43 permeable paving installations in
Rated at 45MPa wet crushing strength, it
the Blue Route development. It involves
the Western Cape,” says Wium.
complies with SANS 1058 : 2010 Concrete
manufactures the blocks for permeable paving SUDS applications in the UK.
some drainage into the ground and the
Permeable paving systems comprise
Paving Blocks. SANS 1083 :2006 Aggre-
discharge of residual water through small
several layers of aggregate which are
gates from Natural Sources is the stand-
diameter pipes into a small tributary of the
topped with concrete block pavers (CBP)
ard specification for the aggregates used.
Keyser’s River.
either for vehicle or pedestrian traffic.
The reservoir or sub-paving material at
The project’s non-permeable surfaces
However, unlike conventional pavers which
Blue Route Mall is optimised to satisfy the
include the Mall’s roof and the immediate
are designed to prevent water infiltrating
Council’s Policy and comprises the following
perimeter of the building, including the
beneath the paved surface, permeable
(see diagram): a layer of Inbitex® geotex-
p ar k ing and pedestr ian ar eas abo v e
paving is designed to do just the opposite.
tile sheeting on the sub-grade; 250mm of
the parking basements. A por tion of
The paving blocks are cast with lateral
clean 53-19mm single-sized crushed stone;
the non-permeable run-off is channelled
100mm of clean single-sized 19-9.5mm
into the permeable paving reservoir and
crushed stone; a second layer of Inbitex®;
the remainder drains into the municipal
a 50mm course of 6mm bedding aggregate;
stormwater drainage via a water channel.
the pavers; and finally a 2,36mm (nominal
Using this method, neither the reservoir
size) crushed stone grit for surface dressing.
nor the stormwater drainage system will
The sub-grade was excavated to provide
be overloaded.
a minimum fall of 1:1000 to fin drain outlets
The design of the Blue Route permeable paving system was also handled by Aurecon, with Wium’s input. It was based on the UK’s
and was compacted as necessary to A close-up view of the permeable paving surface at Blue Route Mall
achieve a G7 Selected Sub Grade layer with a minimum Californian Bearing Ratio (CBR) of 15%. All soft areas were removed and filled with suitable replacement material to provide a stable sub-grade. The lower layer of sub-base material was installed in two separate layers. Each was compacted with a roller until aggregate ‘lock-up’ was achieved. The role played by the Inbitex® sheeting is to filter out or ‘devour’ pollutants using microbes which establish themselves soon after installation. The microbes prevent the Inbitex® from clogging up with pollutants. Blue Route Mall’s Inbitex® was laid with 300mm overlapping joints using double– sided tape to ensure that all the water is
An aerial view of the 45 000m² permeable paving SUDS site at Cape Town’s Blue Route Mall.
PRECAST VOLUME 7 • ISSUE 3 • 2013
filtered by the Inbitex®.
ARTICLE
9
Wium says one of the biggest challenges
the upper voids, the bedding stone and
or expensive and if undertaken regularly, will
with any permeable paving SUDS system
top layer of Inbitex® sheeting may be
certainly extend the system’s functional
is maintenance.
clogged. In such instances a more radical
life,” concludes Wium.
“The site is being inspected frequently
maintenance process, such as replacing
Civil contractors, Martin and East,
to ensur e its pr oper f unc tion, a
the Inbitex® and some of the bedding
were responsible for the earthworks and
process which began immediately after
aggregate, would be required.
the construction of the permeable paving
construction. Par ticular attention is
Generally, maintenance is not onerous
being paid to open the channels and the down-pipes discharging onto the paved surface, as sand, which is easily carried in suspension, can clog the gaps between the pavers. This occurs in the top 1cm of the grit dressing and regular hard brushing is required to ensure that water can get through. “B e si d e s r e g u l a r b r u sh i n g, m o r e vigorous cleaning will take place twice a year. This will involve conventional street sweepers with vacuum cleaners, brushes, water, and low-pressure hosing where necessary. And we have recommended the removal of pavers for inspection every five years in areas we identify as being more clog-prone. In the worst case scenario,
Blue Route Mall’s permeable paving layers.
installation.
10
ARTICLE
Textured concrete panelling graces the western core of No.1 Silo.
Some of No.1 Silo’s textured panelling clearly demonstrating the aesthetic attributes of precast concrete.
This photo demonstrates how the corbels rest on the ledges. The dowels which lock the corbels into position can be clearly seen protruding from the ledge in the foreground. And next to them the HDPE shims which are used to align the panels are also visible.
PRECAST CONCRETE PANELS ADD LUSTRE TO GREEN WATERFRONT OFFICE DEVELOPMENT Over 1 000m² of precast concrete panelling has been used to clad a section of the external façade of No.1 Silo, South Africa’s latest and largest green office building. Completed in September at Cape Town’s V&A Waterfront and spanning 18 000m², it is also one of Africa’s most advanced sustainable buildings.
Services and Rational Fire Engineers) Col-
Incorporating numerous green-design
(CMA) member, Concrete Units.
laboration (Interiors Architects) Most of the development was clad with double glazing, automatically controlled blinds which track the sun, and an external single-glazed skin. The blinds prevent unwanted heat gain and control solar glare
Smooth-face concrete panelling on the western aspect of No.1 Silo nears completion.
and the double-glazing prevents radiant heat loss or gain and maximises views and natural light throughout the building. The panelling was supplied and installed by Concrete Manufacturers Association
attributes, recycled waste and heat, the
According to architect Karien Trengove,
use of seawater in the cooling plant, and
of VDMMA, the panelling was specified to
a roof garden, to name a few, it is one of
dress 280mm masonry cavity walls on the
only two buildings to have been awarded a
building’s two service cores and western
six-star design rating by the Green Building
façade, and to distinguish them from the
Council of South Africa.
glazed façade of the atrium and office
Developed by the V& A Waterfront,
floors. Both textured and flat panels were
No.1 Silo’s architectural team comprised
specified for aesthetic reasons and to give
Van der Merwe Miszewski Architects
different functions unique identities.
A textured concrete panel is lowered carefully into position on the northern aspect of No.1 Silo.
± 128m² and the west core 738m². They
(VDMMA) in association with Rick Brown
One hundred and eighty concrete panel
were manufactured in 17 dimensions, the
& Associates. Other members of the
sections, 120mm thick, were supplied by
smallest spanning 1 590 x 1 750mm and
consulting team included Mace (Project
Concrete Units, 132 with textured (Reckli
the largest extending to 1 705 x 4 295mm.
Managers), MLC (Quantity Surveyors),
Tigris) façades and 48 in flat smooth-face
The smooth-face panels were supplied in
Sutherland Consulting Engineers (Struc-
finishes. The former were used on the
eight sizes and clad a ± 320m² directional
tural Engineers), ARUP (Façade, Wet
service cores - the east core measuring
wall on the western façade. The largest
PRECAST VOLUME 7 • ISSUE 3 • 2013
ARTICLE
11
measured 2 650 x 3 760mm and weighed
panel. Designed to be epoxied into the
lock the corbels permanently into position
3.4 tons. Smaller smooth panels were also
guides of the panels below they provided
after the grouting had been completed
used at the base of the west core to create
a vertical connection between each panel
and they also acted as guiding pins during
a plinth line at ground level.
and facilitated continuity through the panel
installation. High density polyethylene
joints, thereby transferring wind loads to
(HDPE) shims, wedged between the floor
the corbels at each level.
ledge and the corbels, were used to ensure
Structural engineer, Justin Arendse, of Sutherland Consulting Engineers, said a combination of steel sub-frames, corbels
Two further dowels, 20mm in diameter
and dowels were used to anchor the individu-
and also galvanised, were cast into the
al panels to either the façade sub-structure
supporting ledge and epoxied into the
Trengove added that in keeping with the
or the protruding concrete slab edges.
panel corbels. Their prime function was to
design ethos of the building, the overall
that the panels were perfectly aligned before grouting took place.
“Each panel was lowered from the roof
carbon footprints of the panels were re-
into position using a purpose-made six ton
duced through the manufacturing process.
crane and a four-man cage. The reason for
“They were produced using recycled
this was that the project’s tower crane
reinforcing and a slag-waste cement
had a maximum lifting capacity of only one
extender sourced from the Saldanha steel
ton at the end of its reach. Lifting and
mills. Once the moulds were stripped the
then lowering the sections into position
panels were tilted into a vertical position
required meticulous care and coordination
and then stored on an A-frame steel rack
between the cage team and the crane
before delivery to site.
operator and on average only three panels
“Far from being dull and boring this
could be installed each working day,” com-
panelling demonstrates how, when cor-
mented Arendse.
rectly designed and applied, concrete
Two 12mm galvanised steel dowels were cast into the bottom end of each
The six-ton crane, which was purpose-made by Concrete Units to lift the panels into position.
facades can be extremely attractive,” says Trengove.
12
COVER STORY
The pre-heater tower and raw-meal silo at Agangang.
Sephaku’s clinker silos at Delmas.
NEW SEPHAKU PLANT ON TRACK The construction of Sephaku Cement’s 155 ton-per-hour cement milling plant, located to the south west of Delmas in Mpumalanga, is on track to begin production in early 2014. Sephaku engineering project manager, Heinrich de Beer, reports that 90% of the structural steel work which first broke ground in June 2011, has been completed and that the installation of mechanical and electrical equipment is in progress. “This project incorporates the latest
as planned,” explains de Beer.
Non-production buildings currently in progress at the Sephaku Delmas plant include a clinic, fire station, petrol station, administration building, canteen and guard house. Referring to the construction of Sephaku Cement’s flagship plant in Lichtenburg, Aganang, de Beer said that a recent highlight was the turning of the kiln for the
environmentally-friendly technology with
Blowers and compressors have been in-
particular emphasis on high efficiencies and
stalled at the fly ash offloading yard and the
first time through the drive unit. “To date 393 306m³ of earth has been
reduced power consumption,” says de Beer.
extraction system, aeration equipment and
excavated and 72 762m³ of concrete has
Concr ete totalling 35 452m3 and
air slides inside the silos have been installed.
been poured at Aganang. Moreover, 7 700
3 500 tons of reinforcing steel have been
Commenting on the plant’s non-turnkey
tons of reinforcing steel has been used,
used to date. Some of the turnkey project
projects, de Beer says one of the major
15km of earthing cable placed, and 12km
milestones include the completion of a
milestones is the comple tion o f the
of cable trays installed.
30 000 ton clinker silo and the space frame
electrical switch yard and the cabling which
for its roof. Gantry structures, which
runs between it and the main substation.
include sheeting, cabling and lighting, have
“Another is the space-frame structure
been built and so have the stacker and
for the packing warehouse which has also
gypsum store space-frame.
been built. This impressive structure is
“The assembly and installation of the
similar to the roof structure at Beijing’s
Loesche cement mill and classifier, which
airport. The sheeting, which illustrates the
is the heart of the plant, is 90% complete.
size of the warehouse, is almost done and
In addition, electrical cabling throughout
the sheeting which covers the packing plant
the plant is well advanced and proceeding
is likewise close to completion,” he says.
PRECAST VOLUME 7 • ISSUE 3 • 2013
The cement proportioning plant at Delmas.
WE DIDN’T LIST HIS COMPANY ON THE STOCK EXCHANGE We didn’t double his business in the first year We didn’t find him trustworthy employees We didn’t teach him how to build solid structures
WE DID MAKE THE CEMENT HE BUILT HIS REPUTATION ON CREATING POSSIBILITIES
With the planet as one of our core values, we assess the carbon footprint of each and every one of our operations and products while actively striving to drive down our impact on the environment.
www.afrisam.com
14
ARTICLE
with a smooth soffit which can be painted.” S u p p l i e d b y C M A m e m b e r, E c h o Prestress, the hollow-core slabs in use at The William vary between 3.5m and 6m in length and are supplied in three depths, 120mm, 150mm and 170mm. These were specified at the outset by the structural engineers, based on loading requirements. “We are using a conventional precast concrete brick at The William which is supplied by CMA member, Savanna Bricks and Paving. Savanna maintains strict quality controls and delivers an extremely reliable product. We work to a minimum strength rating of 10MPa on our developments and we are averaging 12/13MPa with Savanna. “What we like in particular is that the Savanna bricks don’t vary in size. This means they are easy to lay and plaster.
Prestressed hollow-core slabs supplied by Echo Prestress.
PRECAST CONCRETE PREDOMINATES AT ‘THE WILLIAM’
Some of the other brick suppliers we have used in the past have given us a product which varies in size and strength ratings. “We are also realising substantial time and cost savings on precast concrete staircases which are being supplied to us by Specialist Precast Erections (SPE). The concrete block pavers, which include a 60mm interlocking block and a 60mm bevelled block are being supplied by CMA member, Cast Industries. The latter are being used for the paths and decorative road edgings and the interlockers are being
Concrete bricks, prestressed hollow-core slabs and concrete staircases are some of the precast concrete elements being used to construct 110 eight-unit apartment blocks at The William, a middle-income high-density residential development currently under construction in northern Johannesburg. Other precast concrete products being used include paving blocks, retaining wall blocks, L beams and lintels.
deployed on the roadways,” added Gray.
Each apartment block comprises four
the budget and to ultimately ensure the
(internal electrical); and Rawlins Wales and
storeys which include two three-bedroom
financial viability of the project.
Partners (external electrical).
ground floor units, two two-bedroom units
“Using precast concrete elements
on the first and second floors, and three
assists us with this process in several
one bedroom units on the third floor. The
ways, but maintaining the programme
smallest one covers 40m² and the three-
and ensuring quality are key factors. Take
bedroomed units are 110m² each.
precast hollow-core flooring slabs by way
“Precast concrete is what makes this type
of example; they offer fantastic quality and
of development viable for us,” says Rodney
high standards of finish, and far outweigh
Gray,managing director of Balwin Properties.
in-situ or beam-and-block flooring, which
“We operate in a very competitive
and the entire development is due for completion at the end o f 2015. T he professional team includes: Cimato Moroldo Architects Inc.; Kantey and Templer, civil and structural engineers; Topack Electrical
take weeks to complete.
environment and from the moment we
“Slabs, by contrast, require only a
move on site the clock starts ticking.
matter of hours to install. Thereafter,
It is imperative that we maintain our
grouting and masonry work can begin
programme to ensure we don’t overrun
almost immediately. Moreover, slabs come
PRECAST VOLUME 7 • ISSUE 3 • 2013
The William is being built in six main phases. Construction began in May 2012
One of hundreds of precast staircases supplied by SPE.
16
ARTICLE
CONCRETE BLOCK PAVING CHOSEN FOR PIETERMARITZBURG URBAN RENEWAL PROJECT The City of Pietermaritzburg specified concrete block paving (CBP) as a crucial element in its urban renewal project (PURP) in and around its city hall and other historic structures. The upgrade formed part of an initiative to mark the city’s 175th year . Financed by the Department of Corporate
determinant in the choice of CBP. “Besides their superior load carrying capacity, concrete pavers were chosen
pavers were tested to ensure that they met long-term (20-year) performance and endurance criteria.
because their life cycle and replacement
In addition to supplying the paving blocks,
costs were not only considerably lower
Brickcast in association with Cristatus
than the other materials surveyed, but
Investments, was also responsible for the
were much easier to replace. Loading was
earthworks, the laying of the sub-base, the
important because Chief Albert Luthuli and
new curbing and new pavements.
Burger Streets, which run parallel to each
The sub-base material comprised: two
other, form alternative routes to the N3 in
150mm layers of G7 aggregate: 150mm of
the event of temporary closure.
stabilised C4 aggregate; 150mm of C2 sta-
G o v e r n a n c e a n d Tr a d i t i o n a l A f f a i r s
“CBP requires far less maintenance
(COGTA), the first phase of the renewal
than asphalt and we’ve also installed
Rossouw says the installation of the
project entailed paving ± 2 400m² of
additional cable ducts for electricity and
new paved sections was complicated by
road comprising: a section of Chief Albert
fibre optics so that the pavers won’t have
the fact that several of the underground
Luthuli Street (formerly Commissioner St)
to be lifted for some considerable time.”
service pipes and cable had to be relocated.
bilised sub-base; and 20mm of bedding sand.
which runs between Church Street and
The road-surfacing pavers selected for
The paved section of Chief Albert Luthuli
Langalibalele Street (formerly Longmarket
the project were 80mm Roadliners cast
Street was earmarked by City officials as
St); the intersection of Chief Albert Luthuli
with a 5mm red topping material to blend
a public gathering place and some of the
and Langalibalele Streets; and a section of
with the red brick of the City Hall and the
175 -year celebrations will be staged there
Langalibalele Street.
Tatham Art Gallery. Rated at 38MPa,
during November.
PURP also entailed the installation
they were manufactured by CMA member,
of new street lighting, new pavements,
Brickcast Industries. However, before
concrete curbing and pavement furniture,
they were specified by Hatch Goba, the
as well as the upgrading of other sections of roads in the precinct. Moreover, parking and new signage initiatives were rolled out in tandem with the paving project. Iyer Urban Design and Architects was appointed by the City to examine various street scapes and the company identified enhancement materials which would match the city environment and integrate with a proposed bus rapid transport system (BRT). Iyer and consulting engineers, Hatch Goba, also r esear ched various r oadsurfacing options including clay pavers and coloured asphalt before opting for concrete block pavers. According to PURP project manager, Gaillard Rossouw, of Hatch Goba, life-cycle costs, aesthetics and loading were of particular concern, the latter proving a key
PRECAST VOLUME 7 • ISSUE 3 • 2013
The partially completed sub-base at Albert Luthuli Street, Pietermaritzburg, prior to the laying of 80mm concrete block pavers.
18
ARTICLE
SWAZILAND OPTS FOR PATENTED PRECAST CONCRETE BARRIER SYSTEM
A worker smooths the concrete in a barrier mould.
Safer roads, prevention of cross-over accidents, a system which meets local and international safety standards with an H2 containment level, plus the long-term benefits of reduced maintenance issues and costs - some of the reasons why the Swazi Government chose the internationally patented Delta Bloc vehicle restraint system for a 13.5km stretch of dual carriageway currently under construction between Manzini and the Kingdom’s new Sikhuphe international airport. Together with donor consulting f irm
casting. Delta Bloc South Africa monitors
Sadeem al Kuwait from Kuwait, local
the quality of manufacture daily to ensure
designers, Swaziland Consulting Engineers
compliance with DBI’s standards.
(SCE), specified DB100S barriers designed
Steel reinforced, the barriers attain
by Austria’s Delta Bloc International (DBI)
a strength of 30MPa when cured. The
to meet the international median barrier
correct spacing between the rebar and
standards required for the project. DBI
the mould walls is achieved by the insertion
subsidiary and Concrete Manufacturing
of cover blocks. Four cubic metres of
Association member, Delta Bloc South
concrete is poured into the moulds which
Africa, is supplying the barriers.
are inverted for the pouring process.
Manufacturing is taking place in Swa-
During pouring, which takes place in two
ziland under a project license agreement
stages, the moulds are vibrated to avoid
between Delta Bloc South Africa and
honeycombing.
A void former is removed before the mould is turned upright.
Inyatsi Construction. The barriers, with
After the first stage, void-formers are
a containment level of H2, meet both the
inserted into the moulds to create three
local SANS 51317 and European EN1317
lateral rain water drainage channels as well
Completed barriers prior to installation.
vehicle restraint system standards.
as a central channel which runs the full
to release the concrete elements as it
To be awarded the European standard,
length of each barrier. The latter has no
reduces the possibility of damage to the
barriers have to be physically crash-tested
other function other than weight reduction.
still green concrete.
in a road research laboratory. The test
This is achieved without any reduction in
involves a 13 ton truck or bus travelling at
strength or performance.
Installation of the barriers will begin in late 2013 and will be completed in early
a speed of 70km impacting the barrier sys-
After curing overnight, the barriers
tem at an angle of 20 degrees. The amount
reach a strength of approximately 7MPa.
the barrier system deflects whilst contain-
This is suf ficient to remove the void-
Delta Bloc South Af rica managing
ing the errant vehicle is then measured,
formers and to turn the moulds 180º
director, Garth Strong, says that precast
giving the working width of the system.
2014 once the construction of the road surface has been finalised.
into the upright position. The barriers
concrete barriers perform a vital road-
DB100S barriers are six metres long,
can then be separated from the moulds
safety function. “They prevent high-speed
1m high and weigh 4.5 tons. Eight steel
using hydraulic jacks and special press-out
head-on collisions and pay for themselves
D el t a Blo c moulds manu f ac tur e d by
components placed inside the moulds. This
many times over by limiting injury, fatalities
Formquip in Midrand are being used for the
is preferable to shock loading the moulds
and extensive damage to vehicles.”
PRECAST VOLUME 7 • ISSUE 3 • 2013
20
ARTICLE
MAMMOTH PRECAST CONCRETE CULVERTS CHOSEN FOR TWEEFONTEIN STACKER TUNNELS Eight hundred giant precast concrete culverts, three-and-half metres high and just over five metres wide, are being used for the construction of two coal-buffer (stockpile) tunnels at Glencore’s Tweefontein Optimisation Project near Witbank.
transportation by road. To make up the shortfall, the foundations include elevated uprights measuring 500mm. Once in place the joints between the culverts are sealed with bitumastic sealant on the outside and grout on the inner joints. “Given the culver ts’ non-standard dimensions, six custom-made steel moulds are being used for the casting, which is done horizontally. The moulds were designed and supplied by local steel fabricating company, Mario Meano Engineering. During casting, seven steel 200 x 200mm utility plates are inserted into the inner walls of each culvert. These are being used as attachment points for channelling electrical cabling and piping through the tunnels. Once cured, the culverts are loaded horizontally onto low-bed trucks, each truck carrying two culverts. “The simple and safe handling of the culverts, both at the Brakpan plant and at the colliery also required some additional engineering. Steel lifting beams were designed by Groenewald. Rather than using
In ter na tional c onsul ting engine er ing
engineer, A r thur Oosthuizen, r ecent
additional machinery to shift the culverts
c o n c e r n, D R A M i n e r a l P r o j e c t s, i s
durability and maintenance concerns with
into a vertical position on site, Groenewald
responsible for the engineering, project
steel tunnels and time constraints with
adopted an innovative approach by using
management and construction work. DRA
in-situ concrete construction prompted
the force of gravity. This is done by at-
is also handling the design of the system
the decision to opt for precast concrete.
taching a steel beam to the top end of
in collaboration with civil and structural
“Although the precast concrete approach
the culvert and then by simply lifting this
consulting engineering company, Holley and
is as yet untested in this type of application,
end with a crane, the culvert swings into
Associates. Wilson Bailey Holmes is the
we believe it will become our default choice on
a vertical position. It is then easily raised
main civil and earthworks subcontractor.
future projects,” says Oosthuizen.
and placed into position on the foundation.
This is the first time DRA has used
Weighing 12.8 tons each, these are some
concr ete cul ver ts f or coal stock pile
of the largest culverts ever made in South
tunnels. Steel and in-situ concrete were
Africa and could well be the largest single
also considered. According to DRA project
culvert order ever. Manufactured by Concrete Manufacturers Association (CMA), member, Aveng Manufacturing Infraset, and designed by technical marketing manager, Coenraad Groenewald, they were produced at its Brakpan manufacturing facility. “The units are comprised of solid steelreinforced concrete and are designed to handle well in excess of the maximum 20 ton loading they are likely to encounter at the Tweefontein buffer zones,” says Groenewald. “Each contains 600kg of reinf orced steel and measures 3.5m (height) x 5.3m (width) x 1m (depth). The walls are tapered, measuring 350mm at
A 12.8 ton culvert is moved into position prior to installation on one of the four buffer tunnels at Tweefontein Optimisation Project.
PRECAST VOLUME 7 • ISSUE 3 • 2013
the upper end and 300mm at the base.” The initial requirement was for a height of 4.7m but this proved too large for
Partially completed buffer tunnels.
advertorial
21
PMSA confident of further growth following successful bauma campaign Pan Mixers South Africa (PMSA) has consolidated its reputation as the largest supplier of concrete brick, block and paving-making machinery and technology in Africa - following a highly successful display at bauma AFRICA 2013.
names in the African construction and mining sectors. “The event provided PMSA management an opportunity of networking with new and existing clients in an informal yet professional environment.” Booysen noted further that the global trend of automation is taking hold in South Africa.
PMSA marketing and sales manager Quintin
“Our ongoing labour unrest and rising
Booysen says the company’s indoor and
labour costs make automation an increas-
outdoor displays at bauma, showcased a
ingly attractive option,” he says.
comprehensive concrete technology and
L o ok ing ahe ad B o oy sen said tha t
solutions offering, which was well-received
PMSA’s strategic imperatives in 2014
by thousands of visitors.
would include monthly industry-specific
“Outdoor exhibits included a Fiori
open training and workshop sessions at
self-loading concrete batching vehicle,
PMSA’s showroom and sales facility in Jet
automated RE600 concrete brick and
Park, Boksburg.
block making machines, a wide range of HTC
“These sessions will include input from
floor grinding and polishing machinery and
concrete industry experts drawn from
accessories, and live polishing and grinding
Africa and Europe,” he concluded.
demonstrations,” he explains. PMSA hosted 15 of its international and local suppliers at the event including five
Call 011 578 8700 or email Quintin@ panmixers.co.za for more information on the 2014 training and workshop sessions.
new suppliers. Their representatives were on-hand at PMSA’s indoor stand throughout the exhibition. The new suppliers included: • IMER: An international leader in concrete
batching and mixing equipment
• RAMPF: A specialist in precision block,
brick and paving making moulds
• ABECE: An expert manufacturer of
concrete roof tiling systems
• Turbosol: A pumping technology provider
for the building industry
• Pavatile: An award winning wet-cast
simulated stone mould manufacturer
and supplier Booysen revealed that bauma enabled
PMSA to achieve significant brand building awareness with some of the leading
PRECAST VOLUME 7 • ISSUE 3 • 2013
22
ARTICLE
CMA WELCOMES NEW MEMBERS Since welcoming eight new members in our last issue a further seven members have joined the Association. They are: ASPASA (Aggregate and Sand Producers Association of South Africa); Afrisam; British Precast Concrete Federatrion; The Concrete Society; Dick King Labs; SARMA (South African Readymix Association); and Savanna Bricks and Paving.
associate members, partners, companies and other bodies. It is dedicated to improving the business environment, both short and long term, for the concrete products industry in Great Britain and Northern Ireland. Members’ interests are continually developed by a committed team with extensive connections in the UK and worldwide. BPCF works in several areas, including h e a l t h & s a f e t y, p o l i t i c a l l o b b y i n g, sustainability & environment, training, and marketing & events. As well as exhibiting at external events, it also holds its own national expo and conference annually to showcase members products and services. Our Best Practice Awards celebrate the
Outlined below are brief profiles on some of the new members:
best of industry each year with categories in projects, innovation, health & safety, sustainability, and creativity. Executive director of British Precast,
AfriSam Black-controlled AfriSam is one of the
Andrew Minson, says: “With over 100
most widely spread cement, aggregate
organisational members at BPCF, broad-
and readymix groups in the southern
ranging alliances, and a knowledgeable team
African region, with operations in South
of professionals, we offer a strong and
Africa, Botswana, Lesotho, Swaziland and Tanzania. The company is a proud Level 2
powerful voice within the whole construction A sand quarry which is run by an ASPASA member.
Broad Based Black Economic Empowerment
industry - both nationally and internationally. We are pleased to be a part of South Africa’s
(B-BBEE) contributor and has a 62.5
ASPASA
Concrete Manufacturers Association, and
percent interest in Tanzania-based and
T he A ggr ega t e and S and P r o duc er s
hope to build a long and mutually beneficial
listed Tanga Cement Company Limited.
Association of Southern Africa (ASPASA)
partnership together.”
Founded in 1934, AfriSam employs more
is a voluntary membership, private sector,
than 2 000 staff members and has an
producers association. It is run through
annual cement production capacity of
an executive council and managed by a
5.8 million tons, produced from seven
management committee which supports
production facilities and distributed to
and guides a full-time executive director.
customers through strategically-located cement depots.
Although a member of the Chamber of Mines, ASPASA is an independent organisation which represents producers of aggregate and sand. The Association lobbies national and provincial governments on behalf of its members and liaises with other policymaking and opinion-forming entities and associations, both locally and overseas.
The British Precast pavilion at Ecobuild, the world’s biggest event for sustainable design and construction.
The Concrete Society
Members benefit from a wide range of
The Concrete Society of Southern Africa
services through working committees,
NPC is a non-profit ‘community’ of individuals
especially where individual companies have
(some through their companies) who seek
insufficient resources.
to keep themselves up-to-date with the latest technology and thinking in concrete
The placement of 45t precast antifers on a breakwater at Durban Harbour. AfriSam cement was used for these precast antifers.
PRECAST VOLUME 7 • ISSUE 3 • 2013
British Precast Concrete Federation
an d c o n c r e t e - r e l a t e d m a t t e r s . T h e
British Precast Concrete Federation
Society, through its national and regional
(BPCF) is an industry federation comprising
network, offers seminars, site visits, CPD
concrete product producers and product
accreditation for engineers, publications,
associations, together with a wide range of
student support, excellence awards, and
ARTICLE
creates business opportunities for its individual and corporate members.
23
The company is associated with Moisson Instrumentation which is SANAS ac-
In this way the Society achieves its
credited for handling calibrations in force
overall mission of promoting excellence and
compression, and besides the CMA, Dick
innovation in the design and use of concrete,
King Lab Supplies enjoys membership in
providing a forum for networking and
the following associations: BSI (British
technology transfer between its members
Standards Institution); N.L.A (National
and local and international affiliates.
Laboratory Association); SAFCEC (South African Federation of Civil Engineering Contractors); Sabita (South African Bitumen Association); and the Johannesburg Chamber of Commerce and Industry. SARMA SARMA (The Southern African Ready-mix Association) is a national body which represents South Africa’s reputable ready-mix companies. It advances premix technology through research and participation, is responsible for promoting the ready-mix industry, and promotes ready-mix as the preferred construction material. It disseminates information on the
The De Hoop dam under construction.
current and prospective use of ready-mix concrete to its members and interacts
Dick King Lab Supplies
with authorities, suppliers, customers,
Dick King Lab Supplies has been supplying
specifiers and regulators.
ci v il e ngin e e r ing l ab o r a t o r y t e s ting equipment to local and international concerns for approximately 35 years. Based in South Africa, the company markets its equipment under the Kingtest brand name and manufactures container labs for site use under the brand name Contain-A-Lab. The company also manages several agencies, including: Matest; IPC; Baty; and Proceq Instruments. A readymix delivery.
It also sets standards and guidelines with regard to environmental, safety and quality issues and SARMA membership requires that these stringent policies are met and adhered to. In addition, members are regularly audited against
m
best-practice standards.
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A Kingtest concrete cube press.
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PRECAST VOLUME 7 • ISSUE 3 • 2013
OUR DOOR
IS OPEN BECOME PART OF THE FUTURE
WE INVITE ALL PRECAST CONCRETE MANUFACTURERS TO JOIN US *
m
* TERMS AND CONDITIONS APPLY
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CONCRETE MANUFACTURERS ASSOCIATION 16 Horn Street, Kempton Park, 1620 PostNet Suite 8612, Private Bag X32, Kempton Park, 1620 Tel +27 11 805 6742 • Fax +27 86 524 9216 • E-mail: admin@cma.org.za
www.cma.org.za
APPLICATIONS
25
ECHO PRESTRESS builds HIGH-STRENGTH SECURITY WALL CMA member, Echo Prestress has erec-
Easterhuizen advises that soil condi-
ted a security wall built with its own
tions determine the type of foundation re-
prestressed hollow-core concrete slabs
quired for this type of walling and whether
at its prestressed hollow-core factory in
the slab placement should be horizontal
Chloorkop, Gauteng. Constructed in two
or vertical.
sections, the wall is 275m long and 5,4m
“Clay, collapsible soils, high water tables
high at its highest point. A 0,6m section
and so on require horizontal installations,
of the wall is buried below ground.
whereas better soil conditions are best
The walls comprise five tiers of inter-
suited to vertical applications. Some hori-
locking slabs measuring 6m (length) x 1.2m
zontal placements may also require piling.
(width) x150mm (depth). They were placed
“Wind resistance and stormwater
horizontally and secured into position be-
drainage are other design considerations
tween vertical steel columns.
and so is impact resistance which deter-
Echo Prestress marketing director,
mines maximum wall height and slab depth.
Melinda Esterhuizen, says ther e ar e
Stormwater drainage must be properly
several advantages to this type of wall,
engineered and weep holes, generally 100m
speed of construction, being one of the
in diameter, should be placed strategically
major considerations, cost being another.
for good drainage.
“The current cost of building a security wall using prestressed hollow-core slabs,
Esterhuizen added that precast security walls also have some green attributes.
is approximately half that of an in-situ wall
“The concrete slabs and steel support
offering the same properties; an in-situ
columns are both 100% recyclable and
wall would take two to three times as long
reusable. The wall itself has a very long life
with no advantage gained in strength or
span, is maintenance free, and other than
durability. Moreover, precast walling has
occasional cleaning, no other maintenance
no requirement for shuttering or propping,
is required. However, the steel columns do
onsite curing, formwork or grouting, and
need rust protection.”
the construction rate is approximately 50
Esterhuizen concluded by saying that
linear metres per day (eight hours).” says
a key to the success in constructing
Esterhuizen.
this type of security wall is a very close
T he Echo wall comprises 50MPa
working relationship between the design,
concrete which means even jack hammers
engineering and construction professionals.
would struggle to break through it.
Echo offers design solutions for both
“Intruders cannot scale it, dig under it
precast flooring and security walling
or break through it without making a great
applications. Contact Melinda Esterhuizen
deal of noise and taking a very long time.”
on (011) 589 8800 or 083 605 0077.
A section of recently completed prestressed hollow-core slab walling at the Echo Prestress factory in Chloorkop.
PRECAST VOLUME 7 • ISSUE 3 • 2013
26
APPLICATIONS
AC T0M Air Pollution Control recently completed a turnkey contract for the design, manufacture and commissioning of three high-efficiency bag filters at PPC Cement Slurry’s factory near Mafikeng,
ACTOM executes fast-track dust control contract
North West Province. The installation was
steel and concrete structure, and the
“The short shutdown schedule meant
completed on schedule at the end of April
installation of new bag filters for two new
that the site had to be shared with the
this year with no safety related incidents.
separators. Furthermore, all three filters
other contractors involved in the upgrade,”
The multi-million rand contract, awarded
and associated ducting had to be insulated
Hopkins said.
in May last year, involved the supply of a
and clad during the shutdown phase.
76 000 Am3/hour reverse pulse bag filter to
The main mill bag filter was designed to handle higher dust volumes and all bag filters
replace an electrostatic precipitator (ESP)
were designed to reduce dust emission lev-
at PPC Cement Slurry’s Finishing Mill 4.
els in accordance with the newly legislated
In addition, two bag filters, each with an
2015 environmental emission target of
air moving capacity of 16 000 Am3/hour,
30 mg/Nm3 at high temperatures.
were supplied to de-dust two new high-
Dipeen Dama, PPC’s senior project
efficiency separators that were installed
manager, said ACTOM Air Pollution Control
as part of the upgrade.
implemented all stages of the contract effi-
“One of our challenges was to install
ciently, from design through to installation.
all three bag filters during an eight-week
“Per f ormance testing of the mill-
shutdown period,” said Raymond Hopkins,
bag filter was completed early in July
ACT0M Air Pollution Control’s project
2013. The results of the isokinetic dust
manager on the contract.
sampling measurements confirmed that
“T his involved the dismantling and removing the existing ESP, the installation of a new mill bag filter on the original
the performance of the new mill bag filter The completed 76 000 Am3/hour reverse pulse bag filter at PPC Cement Slurry’s finishing mill 4 near Mafikeng.
met the contractual guarantee of less than 30 mg/Nm3,” he commented.
AFRISAM ADVISES ON CHEMICAL ADMIXTURES In order to ensure concrete blends which
extender content,” says Di Nardo.
which will also attract two points,” com-
are not comprimised in strength or integ-
Cement extenders are finding increasing
rity, AfriSam supplies several chemical
favour from an environmental perspective
In addition to its environmental benefits,
admixture technologies.
as their use results in a large reduction in
cement produced with ‘green’ extenders
the generation of carbon dioxide.
has no negative effect on concrete quality
According to AfriSam’s Furio Di Nardo, one needs to be aware of the challenges associ-
“AfriSam’s ‘green’ cement utilises ex-
ments Di Nardo.
or workability, durability and density.
tenders such as slagment, fly ash and lime-
“In fact, it enhances the workability of
“Some structures, such as concrete
stone to reduce the amount of clinker needed
fresh concrete and makes the end product
bases, allow for increases in the extender
in the cement. The use of these extender
more durable and impermeable. AfriSam
blend of up to 50% replacement proportions.
materials is a classic example of recycling at
will continue to drive research in the use
However, we caution that with more intri-
its best, since most of the material would
of secondary products in green cement
cate structures like floors, surface beds or
end up in landfills,” says Di Nardo.
mixtures as a catalyst for environmental
ated with increasing the extender content.
pavements, one should reduce the extender
The Green Building Council of South
blend to minimise the potential for cracking
A f r ic a (GB C S A ) r ecen tl y r e f ined i ts
and curling. In these instances, an advanced
three-point requirements in lowering
knowledge of curing is a prerequisite.”
concrete’s environmental impact in building
As pressure increases for the construc-
construction. To this end AfriSam has paid
tion industry to reduce carbon footprints,
close attention to the ingredients used in
it is critical that the limitations of concrete
concrete on various building projects.
with added extenders be reviewed carefully.
“An example is Standard Bank’s cus-
“AfriSam has invested substantially in
tomer service office in Rosebank, Johan-
researching the performance of extenders
nesburg, which qualified for two GBCSA
and we are now in a strong position to offer
points in the concrete category. We also
concrete mixes with the same properties
designed custom mixes for Nedbank’s
and performance as concrete with less
new Lakeview development in Roodepoort,
PRECAST VOLUME 7 • ISSUE 3 • 2013
stewardship,” Di Nardo concludes.
AfriSam’s ‘green’ cement utilises extenders such as slagment, fly ash and limestone to reduce the amount of clinker needed in the cement.
APPLICATIONS
27
Eco-Tile® Extrusion for a bright housing future A new concrete roof tile extrusion machine, the Eco-Tile Extruder®, manufactured by Jessop & Associates (Pty) Ltd, was exhibited in September at bauma Africa 2013. According to Grahame Jessop, the founder and managing director of Jessop and Associates, the new machine is capable of producing the same high-quality Double Roman tiles that are made on faster PROTILE® high-speed extrusion plants.
The Eco-Tile Extruder® manufactured by Jessop & Associates.
tile plants and related equipment for nearly
“This means that precision extruded
30 years, having supplied and installed over
concrete roof tiles can now be produced
50 tile plants in 18 African countries and
on a much broader geographic footprint,
many more elsewhere in the world, making
and at a very favourable cost. The Eco-Tile
us Africa’s very own global equipment
Extruder® is capable of extruding tiles
supplier,” said Jessop.
based on the thinner, more cost-effective
The Eco-Tile Extruder® concept drew
range of the SABS quality requirements
much attention at Jessop & Associates’
i.e. 11.0mm thick, and weighing 4.2kg per
bauma Africa 2013 stand. Many CMA
tile or 42kg/m2 roof installed. Normally
members visited the stand, some of whom
low capacity machines struggle to achieve
have been customers for many years. “We also exhibit regularly at BAUMA in
this quality. “Our entire range of equipment was
Germany - the largest machinery show of
born and bred right here in South Africa.
this kind in the world - and it has assisted
We have been manufacturing concrete roof
us in growing our PROTILE® brand globally.
Swiss watch technology inspires greater moisture measurement accuracy
The Hydro-Mix VII.
Leading process en-
chutes and holding hoppers, and copes
gineering firm, Birk-
very well with fluctuations in temperature
enmayer, has intro-
without compromising results.
duced the state-of-
With a measurement rate of 25 times
the-ar t Hydr o-Mix
per second and a choice of measurement
VII moisture sensor,
modes for optimised sensor performance
which measures to 0.1% accuracy and is
in a range of applications and material
ideal for the concrete industry. Made by
types, the Hydro-Mix VII is essential for
British moisture measurement technology
accurately controlling water addition
manufacturer, Hydronix, the Hydro-Mix
during the mixing and drying processes.
VII was inspired by the bimetallic strip on
It inter f aces with the Hydr o-Com
mechanical Swiss watches, which remain
software from Hydronix for continuous
indifferent to temperature changes.
monitoring via USB or Ethernet, and is
Building on the success of the existing
extensively supported by Birkenmayer in
Hydronix’ range of moisture measurement
South Africa, as well as by Hydronix’s
devices which is also available locally
global exchange programme.
through Birkenmayer, the Hydro-Mix VII can be fitted flush onto screw conveyors,
For more information on the Hydro-Mix VII, call Birkenmayer at 011 970 3880.
PRECAST VOLUME 7 • ISSUE 3 • 2013
28
CMA MEMBERS
Producer members company name
telephone
PROVINCE
Pillar
A Fick Sementwerke
(022) 913 2370
WC
PB
Aveng Manufacturing Infraset
(011) 876 5500
JHB
PB/PI
Bass Beams
(031) 784 1920
KZN
PB
Bay Brick
(035) 792 5218
KZN
PB
Beta Tiles
002634 2925303
ZIM
PB
Boland Concrete
(021) 875 5365
WC
PB
Bosun Brick Midrand
(011) 310 1176
JHB
PB
Brickbuild t/a Panda
0026 244 2107/8
BOTS
PB/PI
Brickcast Industries cc
(031) 507 5525
KZN
PI
Vaka Concrete (Pty) Ltd
C.E.L. Paving Products
(021) 905 5998
WC
PI
Vanstone Precast (Pty) Ltd
Cast Industries
(011) 316 2375
JHB
PB/PI
Colonial Stone
(011) 794 9737
JHB
PB/PI
Concrete Units
(021) 386 1923 (016) 362 2236
WC/JHB
PB/PI
Conframat
(0861) 33 5599
JHB
PB/PI
Corobrik (Pty) Ltd
(031) 560 3111
KZN
PI
company name
telephone
PROVINCE
Pillar
Rocla
(011) 670 7600
JHB
PB/PI
Savanna Bricks & Paving (Pty) Ltd
(012) 809 1197 086 559 28744
JHB
PB/PI
Shukuma Flooring
(041) 372 1933
EC
PB
Southern Pipeline Contractors
(011) 914 8500
JHB
PB/PI
087 941 3889
JHB
PB/PI
Technicrete
(011) 674 6900
JHB
PB/PI
Topfloor
(021) 951 7700
WC
PB
00263 8644 08100
ZIM
PB/PI
(012) 541 2056/1808
JHB
PI
(011) 851 1098
JHB
PI
Style Decor Design & Manufacturers
West End Cement Bricks
PI - Precast Infrastructure PB - Precast Building
Associate Members telephone
PROVINCE
ASPASA
(011) 791 3327
JHB
ARQ Consulting Engineers
(012) 348 6668
JHB
0044 116 253 6161
UK
company name
Deranco Precast Deranco Blocks Deranco Paving (Pty) Ltd
(041) 933 2755
EC
PB/PI
Eagle Roof Tiles (Pty) Ltd
(044) 874 0290
EC
PB
British Precast Concrete Federation
Echo Prestress (Pty) Ltd
(011) 589 8800/8899
JHB
PB
Concrete Society
(012) 348 5305
JHB
Fastdeck (Pty) Ltd
0026737 71321528
BOTS
PB
ILIFA Africa Engineers (Pty) Ltd
(016) 981 0591
JHB
Inca Concrete Products
(021) 904 1620
WC
PB/PI
JC Paving Consulting
(011) 431 0727
JHB
Inca Masonry (Garden Architecture)
(043) 745 1215
EC
PB/PI
Pipeline Installation Professional Engineering
(012) 644 0043
JHB
082 850 3512 082 442 2082
JHB
PI
Sekhukhune & Associates
(012) 993 4776
JHB
Kwena Concrete Products
00267 3922850
BOTS
PB/PI
SNA Civil & Structural Eng
(012) 842 0000
JHB
Lategan Cement Works
(021) 873 1154
WC
PB
SARMA
(011) 791 3327 086 647 7967
JHB
Marley Roofing
(011) 316 2121
JHB
PB
Terraforce (Pty) Ltd
(021) 465 1907
WC
Mobicast
(044) 874 2268
WC
PB/PI
Tjeka Training Matters
(011) 665 2777
JHB
(011) 222 7300/7408
JHB
PB
Young & Satharia Consulting Civil Engineers
(031) 207 7252
KZN
(012) 386 0050
JHB
PI
Namib Roof Tile Com/t/as Swakop Tiles cc
0061 222 965
NAM
PB
ReMaCon Products cc
011 393 5504
JHB
PI
Revelstone
(0861) 173 835
WC
PB
Reya Pele Bricks Ltd
(016) 363 0340
JHB
PB
Keystone Walling
Monier Roofing South Africa MVA Bricks
PRECAST VOLUME 7 • ISSUE 3 • 2013
cement members telephone
PROVINCE
AfriSam South Africa (Pty) Ltd
(011) 670 5500
JHB
PPC Ltd
(011) 386 9000
JHB
company name
CMA members
29
non-producer members telephone
PROVINCE
Abel Equipment
(044) 874 1876
EC
Ash Resources (Pty) Ltd
(011) 886 6200
Birkenmayer H (Pty) Ltd
telephone
PROVINCE
Manitou SA (Pty) Ltd
(011) 975 7770
JHB
JHB
Mapei SA (Pty) Ltd
(011) 552 8476
JHB
(011) 970 3880
JHB
Pan Mixers SA (Pty) Ltd
(011) 397 3754
JHB
BASF Construction Chemicals South Africa (Pty) Ltd
(011) 203 2400
JHB
Sika South Africa (Pty) Ltd
(031) 792 6500
KZN
Smartstone (Pty) Ltd
(011) 310 1161
JHB
Chryso Southern Africa (Pty) Ltd
(011) 395 9700
JHB
0048 480 369 0811
POL
Delta Bloc South Africa (Pty) Ltd
(011) 024 4604
JHB
(021) 535 4455
WC
Dick King Lab Supplies
(011) 499 9400
JHB
00264 61 213 632
NAM
Kaytech
(031) 717 2300
KZN
Kerneos Aluminate Technologies
(011) 444 3090
JHB
003111 356 2460
NETH
company name
Kavango Block Brick
company name
Techmatik SA Technical Finishes
CONTRACTOR members company name
Kobra Moulds B.V.
telephone
PROVINCE
Decorton Retaining System
(021) 875 5155
WC
Friction Retaining Structures (Pty) Ltd
(011) 608 4321
JHB
PYW Paving
(031) 903 1736
KZN