PRECAST VOLUME Seven ISSUE 1 • 2013
the cma – QUALITY CAST IN CONCRETE
• A push for wider precast concrete usage • PPC – a true South African success story • CBP used extensively in Klapmuts
contents
1
precast contents message from the executive director 2 calling for new members
NEWS
22 armorflex lining protects embankments at silica mine 23 chryso products ideal for precast concrete wind turbines 25 lafarge’s cem ii aimed at precast concrete producers
3 sika sets up new
27 retaining walls offer varied
concrete laboratory
form and function
3 cma appoints new executive director
PRECAST VOLUME SEVEN ISSUE 1 • 2013
ON THE COVER
A cross-sectional view of the Isibonelo Colliery bunker under construction showing cast in-situ vertical columns, sloping precast concrete beams, precast panelling, and a cast insitu bunker floor, approximately one metre thick. See page seven for details of this case study which illustrates the advantages and flexibility of hybrid concrete technology. THE CMA – QUALITY CAST IN CONCRETE
4 BRIAN shackel – an obituary 4 sephaku cement builds integrated clinker/cement plant
• A push for wider precast concrete usage
• PPC – a true South African success story • CBP used extensively in Klapmuts
5
C&CI to close
5 afrisam regrets c&ci closure
ARTICLES 7 engineers push for wider precast concrete usage
Precast is the official journal of the Concrete Manufacturers Association (CMA) 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, Website: www.cma.org.za
10 ppc: a true south african
Publishers
success story
Isikhova Publishing & Communications
16 concrete block paving and
PO Box 651793, Benmore, 2010, South Africa Tel: +27 11 883 4627, Fax: +27 11 883 4627 Website: www.isikhova.co.za
precast concrete used extensively
in klapmuts housing project
Publisher: Andrew Meyer Tel: +27 11 883 4627, Cell 082 456 5175 E-mail: andrewm@isikhova.co.za Editor: David Beer
APPLICATIONS
Tel: +27 11 478 0239, Fax: +27 11 678 0254 E-mail: bigsky@ibi.co.za Advertising: Marni du Toit
18 safer scaffolding needed – MBA 18 afrisam re-engineers cement portfolio
Tel: +27 11 883 4627, Cell: 084 941 2469, E-mail: communications@isikhova.co.za Design, layout and production: Joanne Brook The views and statements expressed in this publication are not necessarily those of the editor or the publishers and neither he/
21 chatsworth precast concrete pavers going strong
48 years on
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.
PRECAST VOLUME 7 • ISSUE 1 • 2013
2
MESSAGE FROM THE EXECUTIVE DIRECTOR
CALLING FOR NEW MEMBERS • A quality assurance system is in place
Material published by an association on
• Occupational, health and safety (OHS)
the other hand comes across as being
authoritati ve, application-dri ven and
procedures are in use
• Technical and engineering competence • Financial stability • Environmental compliance.
therefore influential. “Moreover, the CMA is the voice of the precast concrete industry. We are known to and engage with national and local
CMA Executive Director Wally Armstrong.
Benefits of CMA membership
governments in lobbying for the greater
• Being part of an association brand
use of precast concrete.
which is widely recognised and respected
“O u r s e m i n a r s, w h i c h a r e o f t e n
f or setting and maintaining best-
presented by overseas experts, are highly
practice standards
regarded by construction professionals
• Access to industry-specific statistical
and local authorities. The focus is on
information
providing practical and technical advice
• Posting CMA logo on company stationery,
which can be readily applied.”
website, packaging and products
A nother bene f it o f CM A member -
The Concrete Manufacturers Association
• Participation in the prestigious Awards
ship is the promotion of high-quality
(CMA) has broadened its membership base.
precast concrete in the technical press.
Unlike in the past when membership was
• Listing on the CMA website
The CMA runs a very successful public
dependent on certain product categories,
• Inclusion on the CMA mailing list
relations programme on precast concrete
membership is now open to any precast
• Membership discounts on seminars and
and its application, enjoying widespread
manufacturer providing certain conditions
editorial coverage across most of the
are met.
• Participation in setting national stand-
country’s construction-related media.
Moreover, it publishes its own magazine,
C M A e x e c u t i v e d i r e c t o r, W a l l y
for Excellence competition
educational courses ards for the industry
Armstrong, says the CMA promotes the
• Access to best-product design and
Precast, which is exclusively devoted to
widespread use of precast concrete and
precast concrete.
lobbies for best-practice standards in its
• Access to a pool of experts
manufacture and application.
• Access to technical literature
pursued by us than individual companies,”
• Opportunities to feature innovative
concludes Armstrong.
“We collaborate with the South African
manufacturing processes
“Again, these activities are more easily
Bur e au o f S t andar ds in in tr o ducing
pr ecast concr ete pr ojec ts in the
and revising industry standards, stage
CMA’s magazine, Precast
seminars, and publish technical literature
• Client referrals
of one’s pr of essional colleagues and
on precast concrete applications. Over
• Networking opportunities
the exchange of ideas. Participation in
the past 10 years we have been active
• Participation in and product displays
our prestigious Awards for Excellence
in promoting skills development and job
at exhibitions.
competition, held every second year, is
creation, and our producer members have
Like the SABS mark, the CMA logo is
yet another.
introduced several innovative precast
a widely recognised and respected brand,
The CMA has done much to grow the
concr e te pr oduc ts w hich ha v e been
a badge of quality if you will, and many
pr ecast concr ete industr y since our
used to enhance quality-of-life across all
construction professionals in the private
inception 40 years ago. We also know that
spectrums of society.”
and government sectors insist on CMA
the future potential for growth is huge.
members’ products.
We intend unlocking this potential over
Armstrong says that for CMA member-
Other benefits of CMA membership include access to the technical expertise
the coming years and we hope you’ll join
ship purposes, precast concrete is defined
“O n e b en e f i t o f asso cia ti ons like
as a concrete product cast in a re-usable
the CMA is that we are able to pro-
mould or form, cured in a controlled
mote precast concrete far more effec-
For f ur ther inf ormation contact
environment, transported to site and
ti v e l y th an in di v i du als th em s e l v e s,”
Pam Zukor on (011) 805-6742 or admin@
lifted into position.
comments Armstrong.
cma.org.za. P
Membership is granted on the basis of
handbooks could be and sometimes are
the following:
published by individual companies. The
• Production takes place in a purpose-
disadvantage is that company literature
is generally regarded as a hard sell.
“For example, technical manuals and
built manufacturing facility
PRECAST VOLUME 7 • ISSUE 1 • 2013
in this process.
NEWS
3
SIKA SETS UP NEW CONCRETE LABORATORY Sika has opened a concrete laboratory in
water-cementitious binder contents,
Gauteng, offering high-quality technical
while maintaining concrete workability and
support in the optimisation of concrete
strength development.
mixes f or semi-dry pavers, wet-cast
Fully functional, with brand-new equip-
precasters, RMC (ready mix concrete)
ment and skilled technologists on hand,
producers, and for testing shotcrete
Sika’s concrete lab is ready for business.
materials used in tunnelling and mining.
This additional laboratory means that
Mixes can be designed and tested
tests can be conducted more efficiently
for maximum per formance at the
and customer s ar e o f f er ed a v alue-
laboratory. Sika admixtures can reduce
added service.
Sika’s new laboratory in Gauteng.
CMA APPOINTS NEW EXECUTIVE DIRECTOR Wally Armstrong has been appointed
as vice president until 2005, and was then
last 10 as marketing director – where,
executive director of the Concrete Manu-
appointed president of the Association.
among other notable construction-related
facturers Association (CMA). Armstrong
Armstrong also heads a marketing
achievements, he established a separate
has had a long and mutually beneficial
consultancy, AMA Marketing, which he
division for precast concrete poles and
relationship with the CMA. He co-founded
established in 2005. During the previous
introduced an entrepreneurship training
the P.I.P.E.S. Division in 2001, which he led
21 year s he worked f or Rocla - the
academy for the previously disadvantaged.
Not all kerbs are the same... Introducing the Bosun Castle Bottom Kerb.
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4
NEWS
Brian Shackel – an obituary World renowned paving engineer, Australia’s
Part of his local research involved
Dr Brian Shackel, lost his battle with cancer
ex tensi v e testing on the shape and
on 18 November last year. He was known
thickness of local concrete paving blocks,
Brian taught pavement engineering
to and well liked by many in the precast
on the quality of bedding sand and how it
at the University of New South Wales at
concrete paving industry, especially to
affected paving installations. His work had
both undergraduate and post-graduate
members of the South African Concrete
a profoundly positive impact
levels f or more than 35
Manufacturers Association (CMA ), to
on the local paving industry,
years and was well known
whom he was both friend and mentor.
transforming it into a world
to international audiences,
leader in Concrete Block
having travelled and
Paving (CBP) technology.
lectured extensively in 24
A former professor of the University of New South Wales, Brian visited this country
Olympics won him a further award from the CIA in 2001.
regularly, his last stopover was in 2010
Brian published three
countries, which besides
when he ran a series of seminars on perme-
books on CBP and his work
South Africa, included the
able concrete block paving (PCBP) systems.
on paving design software,
USA, Canada and many
However, his ties with South Africa
L ock Pa v e, won him an
European destinations.
stretch back to the early eighties when,
Award for Excellence from
In addition to his academic
over two years, he conducted accelerated
the Concrete Institute of
pursuits, Brian also worked
testing of local roads and airport paving
Australia (CI A ). He also
in Pretoria for the CSIR’s National Insti-
co-authored PermPave, custom-made
tute for Transport and Road Research.
software for South African permeable
on many projects worldwide. He was
There was no official paving block standard
paving installations.
especially celebrated for his contribution
Dr Brian Shackel
as a consultant for asphalt,
block paving and rigid concrete pavements
back then and Brian’s research provided
He published more than 100 research
to heavy duty pavements, including those
the basis for subsequent SABS stand-
papers dealing with geomechanics and
for ports, container handling facilities and
ards in the manufacture and application of
pavement engineering, and his involvement
airports, and he was a recognised authority
paving blocks.
as paving coordinator for the Sydney
on ecological and permeable paving systems.
SEPHAKU CEMENT BUILDS INTEGRATED CLINKER/ CEMENT PLANT IN NORTH WEST PROVINCE Sephaku Cement is erecting an integrated
will produce 6 000 tons of clinker a day and
most of the construction components on
clinker and cement plant, Aganang, in North
1.2 million tons of cement a year. It will also
site included:
West Province. At a cost of R2,8 billion, it
compete head-on with other major cement
• An eight-week site preparation in which
is also one of the country’s largest capital
producers and will go to market with the
some some 128 000m 3 of cut and
projects currently under construction.
same grades.
155 000m3 of fill were processed
Aganang will utilise the limestone
Heinrich de Beer, Sephaku Cement
deposits of the Stiglingspan and Verdwaal
engineering project manager, comments
farms situated some seven kilometres
that with a storage volume of 56 000 tons,
• T he 15m (height) x 8m (diameter)
south west of Ltoseng and 25km west of
its clinker silo will be one of the largest of
concrete cone in the raw-meal silo
Lichtenburg. When commissioned at the
its kind in South Africa.
was completed in just 10 days
end of the year, the state-of-the-art plant
“Its kiln too will be the country’s largest and longest burning. The plant’s raw meal
The Sephaku cement/clinker plant under construction.
PRECAST VOLUME 7 • ISSUE 1 • 2013
• Slip-forming at 4m lifts every 24 hours, a rate exceeding the industry average
• Brick-laying teams laid between 1 000
and 1 200 bricks per layer, per day.
silo capacity will be 20 000 tons and its
Sephaku Cement was founded in 2006
finished-cement storage capacity will be
and Aganang is the first clinker factory to
approximately 22 000 tons. Some 13 000
be built in South Africa since 1934. The
tons of rebar was used in its construction
company is a 64% owned subsidiary of
and standar dised shu t ter sizes and
Dangote Cement Plc and is an associate
uniform foundations have led to impressive
of JSE-listed Sephaku Holdings limited.
construction speeds.”
Dangote has invested more than R1 billion
De Beer said that some of the
in the venture, representing the largest
efficiencies achieved through using small
investment in a South African enterprise
structured teams as well as manufacturing
by an African company to date.
NEWS
5
C&CI to close After 75 years of serving the construction
T he pr ocess r equir ed to gi ve e f f ect
and the services normally provided by the
industry in South Africa, the Cement &
to this decision will commence with
Institute will be severely curtailed.
Concrete Institute will be closing down.
immediate effect (27 Feb 2013) and is
More detailed announcements will be
This decision was reluctantly taken by
expected to take two to three months
made in this regard as soon as information
the C&CI board following the resignation
to complete in its entirety. During this
is available.For further information, contact
of the Institute’s main funding members.
period the closure will be the main focus
Bryan Perrie, C&CI MD on Tel 011 315 0300.
Afrisam regrets C&CI closure It is with regret that AfriSam confirms that
from the Cement and Concrete Institute.
products to suit particular specifications
the Cement and Concrete Institute will be
As part of the closure process, AfriSam
and applications. AfriSam’s Centre of
closing down. This follows the withdrawal
will participate in the steering committee
Product Excellence supports customers by
of funding from some of the key funding
meetings and will play an active role to
providing scientific and technical expertise
members. AfriSam believes in the value that
ensure that this process is conducted in a
as well as innovative technical solutions.
the Cement and Concrete Institute offered
professional, fair and responsible manner.
AfriSam would like to use this opportunity
the construction industry and explored
AfriSam is regarded as one of the
to thank the Cement and Concrete Institute
various other options in an effort to sustain
preferred technical centres in the country
for the valuable role it has played in promoting
this industry body. Unfortunately, no
and its product development team in
the interest and general advancement of the
solution could be found. As a result, AfriSam
Roodepoort, Johannesburg work closely
cement and concrete industries as a whole
had no choice but to tender its resignation
with customers to develop and test
in southern Africa over the past 75 years.
PAVING DOESN’T HAVE TO BE BRICKS.
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Natural Beauty Yet Engineered Quality
ARTICLE
engineers PUSH FOR WIDER PRECAST CONCRETE USAGE A special task group comprising consult ing engineers, specialist precast concrete contractors, main cont ractors, academ ics and an architect, has been formed to promote the greater use of precast concrete construction in South Africa.
“Not that long ago it was far more widely
7
or precast in a factory environment. All of these techniques can be combined in a single project. Moreover, individual c oncr e t e elemen t s c an b e de signe d and built combining in-situ and precast concrete in what is known as hybrid concrete,” Theodosiou explains. “Hybrid concrete takes full advantage of the inherent qualities of both forms of casting. The accuracy, speed and highquality finish of precast components can be combined with the economy and flexibility of cast in-situ concrete.
used. For example, half the Sandton City
“For instance, hybrid concrete con-
retail, commercial and hotel development
struction simplifies the more complex
in Gauteng, as well as buildings in Sand-
connection details sometimes associated
ton’s business precinct were built using
w i th n o r m al p r e c as t c on cr e t e c on -
precast concrete elements; so was much
struction. It also allows engineers to
of Sun City.”
design structures or elements with full
Theodosiou believes structural precast
continuity, similar to that found in in-situ
concrete contractors could do much more
construction, as opposed to pin-joint
to market their products and expertise
designs which are sometimes associated
One of its members, structural engineer,
among structural engineers and other
with precast concrete.
G ar y T heodosiou, say s constr uc ting
professionals.
“H y br id concr e te constr uc tion
with precast concrete elements offers
“Property developers are missing out on
p r o du c e s simp l er m o r e c omp e ti ti v e
several advantages. These include: quicker
the superior design opportunities offered
structures. The client is given better value
construction owing to reduced propping;
by precast concrete, particularly in the
and the contractor benefits from increased
improved and consistent quality thanks to
use of columns, beams, and staircases.
off-site component manufacture, safer
the controlled environment that factory-
Professionals who tend to favour structural
and faster construction and consistent
based production provides; and enforced
steel as a faster construction technique
performance,” he adds.
coor dina tion and teamwor k because
are probably unaware of the quick lead
Theodosiou says precast concrete
construction, layout and connection details
times and the huge amount of flexibility
construction addresses all the important
have to be planned well in advance.
offered by precast concrete.
requirements for sustainable concrete
“Despite these benefits precast con-
“As a building material, concrete can
crete falls considerably short of its full po-
either be cast in-situ, precast on site, as
tential in this country,” says Theodosiou.
in the case of tilt-up and stack-casting,
An external lateral view of the Isibonelo Colliery bunker, showing the vertical cast in-situ columns, precast concrete sloping beams and the precast panelling.
PRECAST VOLUME 7 • ISSUE 1 • 2013
8
ARTICLE
structures, including durability, quality, and speed of construction, appropriate finishes and cost-effectiveness. “Concrete, both in-situ and precast, is one of the world’s most durable materials. Well-designed, well-produced concrete offers exceptional performance and long life, and is a first line of defence against most forms of erosion.” Precast production facilities can either be situated in an established factory or on site. Because precast concrete is produced in a controlled environment (typically referred to as a precast yard), it is possible to monitor all stages of production including curing, compaction, the quality and depth of cover concrete, and strength requirements. Precast concrete is generally cast at
A cross-sectional view of the Isibonelo Colliery bunker under construction, showing cast in-situ vertical columns, sloping precast concrete beams, precast panelling, and a cast in-situ bunker floor, approximately one metre thick.
ground level which assists with safety and productivity and offers greater control
Case study: Isibonelo Coal Bunker
caused by the loading and off-loading of coal
of quality and workmanship, unlike the
An 8 000 ton coal bunker at Anglo Coal’s
in the bunker could be resisted.
exposed and awkward access presented
Isibonelo Colliery illustrates the advantages
T he panels wer e cast horizontally
by in-situ casting. In addition, the precast
and flexibility of hybrid concrete technology.
under ideal conditions and after seven
route often results in better durability with
Designed by Lyonell Fliss & Associates and
years of continual usage, the concrete
consequent savings in maintenance costs,
constructed by Murray and Roberts in
shows no visible sign of deterioration. By
time, materials and energy.
2005, the foundations and columns were
contrast, in-situ constructed coal bunkers
constructed with in-situ concrete.
usually require 50mm thick steel plates
Moreover, the forms used in precast concrete production may be re-used
The horizontal bottom slab was cast in-
or rail liners for added wear-protection.
hundreds if not thousands of times be-
situ on precast beams which in turn rested
This is because in-situ casting in sloping
fore being replaced. This ensures that
on in-situ columns. The remainder of the
formwork often results in honeycombing
the costs of formwork per unit are lower
bunker, including inclined and vertical wall
and inadequate compaction, leaving a
than that of in-situ construction, where
panelling, as well as sloping beams, were
30MPa concrete vulnerable to the abrasive
formwork can cost between 35 - 60 % of
all constructed with precast concrete
nature of sliding coal.
the cast elements.
elements and lifted into position by crane.
Controlling quality standards is much
The use of both in-situ and precast
easier in a precast yard and concrete
concrete meant that connecting the
elements which don’t meet the quality
various concrete elements to each other
requirements can be rejected before instal-
was considerably simpler.
lation. It is far more difficult to assess and
A considerable amount of time was
maintain quality in an in-situ constructed
saved by casting the precast elements in
bunker, where climbers are required to
concert with the excavation work and the
assess and repair poor quality concrete
in-situ construction of the foundations,
in awkward dangerous positions/heights.
columns and the horizontal floor-slab. This
In short the advantages of constructing
meant that the precast elements were
the concrete bunker walls and floor in
ready to be lifted into position soon after
precast concrete as opposed to in-situ
the in-situ concrete columns had been
concrete are as follows:
completed.
• Cost savings on steel plate or rail liners
A no ther bene f i t o f using pr ecast
A precast panel is lifted into position prior to installation on the sloping wall of Isibonelo Colliery.
PRECAST VOLUME 7 • ISSUE 1 • 2013
• Better concrete durability
concrete for the bunker was the quality and
• Easier jointing
finish of the concrete panels used to build
• Speed of construction
the inclined and vertical bunker walls. A 60
• Cost savings due to less labour and
MPa concrete with a surface hardener was
specified to produce a smooth, durable and
• Superior quality resulting in less
hard-wearing surface so that the abrasion
maintenance.
material required P
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10
ARTICLE
De Hoek Plant.
PPC: A true South African success story PPC Ltd is the leading supplier of cement in southern Africa. Based in South Africa, Botswana and Zimbabwe, the PPC’s manufacturing facilities and milling depots have the capacity to produce eight million tons of cement per annum. The group also produces aggregates, metallurgical-grade lime, burnt dolomite and limestone. In addition to serving its domestic markets, cement and lime are also exported to other African countries.
Limited, and went on to declare its first dividend, a trend which it still follows to this day. PPC’s expansion into the south PPC continued to grow, acquiring Northern Lime Company (PPC Lime) in the then Northern Transvaal in 1907 and a Slurry f ac tor y in 1916, in the Nor th West
PPC Ltd’s roots date back 121 years
Where it all started
Province. In 1921, PPC established Cape
to 1892, when it established South
Established as De Eerste Cement Fabrieken
Portland Cement and built a factory at De
Africa’s first cement plant. In 2010, PPC
Beperkt in 1892, PPC has tracked the
Hoek, near Piketberg in the Western Cape.
Ltd celebrated its centenary year on the
growth and development of South Africa,
Johannesburg Stock Exchange, joining an
producing the cement used in many of the
extremely small and elite group of listed
country’s iconic landmarks and construc-
centenarians, not only in South Africa but
tion projects, including the Union Buildings,
worldwide.
Gariep Dam, Van Staden’s River Bridge,
To r emain the mar ke t leader, the
Gautrain, Medupi Power Station, the new
cement giant has continuously improved its
Cape Town Stadium in Green Point and much
process technology to meet the country’s
of southern Africa’s infrastructure.
cement needs and to enhance productivity and efficiency at its factories.
PRECAST VOLUME 7 • ISSUE 1 • 2013
In 1908, the company changed its name to the Pretoria Portland Cement Company
JSE - Hollard Street.
ARTICLE
11
This quarry, together with the Laezonia
One of Gordhan’s focus areas is to
Quarry in Muldersdrift and the Kqale Quarry
engage with Government, contractors and
in Botswana, makes up PPC Aggregates.
banks on the Government’s long-stalled
PPC was included in the FTSE/JSE Top
infrastructure programme. PPC will also
40 Companies Index in 2003 and in 2006,
consider participating in private-public
it joined the JSE Socially Responsible
partnerships (PPPs).
Investment Index.
“We have a capacity that the government
Since unbundling from Barloworld in
may not always have. I want to engage more
2007, PPC concluded a R3,9 billion broad-
effectively with government,” said Gordhan.
based black economic empowerment transactions in 2008 and 2012, commissioned a
The modernisation of PPC
R1,4 billion clinker plant in Dwaalboom and
PPC has embarked on a modernisation
completed the R700 million mining facility
campaign which will ensur e that the
at its Hercules plant.
company has competitive, energy efficient plants which will comply with future changes
Rhodes Memorial.
PPC’s expansion into the rest of Africa
in South African environmental legislation.
PPC is a truly African success story –
Part of this process involves upgrading The
a focused business that reflects the
Riebeeck and De Hoek cement factories,
strengths of its people, products and
which when completed, will be able to meet
services. The group’s expansion into the
the Western Cape’s cement demand for the
rest of Africa is based on a business model
next three decades.
of sustainability and brand dominance in its chosen markets. The group aims
Technology upgrades at PPC plants
to grow into a leading emerging-market
A new si x-st age pr ehe a ter k iln was
The company entered the Eastern Province
business, starting in sub-Saharan Africa.
commissioned in 2008 at PPC’s Dwaalboom
in 1927 with the establishment of the
Maintaining its performance and industry-
factory, making it one of the most efficient
Eastern Province Cement Company, and
leadership in its historical markets is
clinker production kilns in South Africa.
the construction of a cement factory on
crucial to this strategy.
the outskirts of Port Elizabeth.
In 2010, PPC commissioned a new
PPC began making in-roads into the
vertical roller mill for cement grinding at its
Always at the forefront of innovation,
rest of Africa via acquisitions in 2012. This
Hercules factory that significantly reduces
PPC converted its slurry factory from a
included a 27% stake in Ethiopia’s Habesha
milling energy costs.
wet process to the more efficient and
Cement Share Company for R100 million
Sinc e 20 03, PP C has b e en c o -
cost-effective dry-mix system in 1958 and
and a 51% stake in Rwanda’s Cimerwa for
pr ocessing al ter na ti v e f uels, and is
a second Western Cape cement factory was
R630 million. And in February this year,
commissioned at Riebeeck in 1960.
PPC announced its intention to invest in
PPC became a subsidiary of the Barlow
a new one-million-ton-per-annum cement
Rand Group in 1977.
plant in Harare.
PPC in the new South Africa
Recent developments
After Nelson Mandela became the first
Last year, Pretoria Por tland Cement
democratically elected president of South
Company Limited changed its name to
Africa in 1994, PPC reached an agreement
PPC Ltd.
with the Botswana Development Corpora-
The name change is premised on a
tion to construct a cement blending plant
streamlined corporate structure with
and depot in Gaborone, which was commis-
discrete South African and international
sioned two years later.
operating entities. All South African
In the same year, PPC launched the first branded general-purpose cement,
operations will be divisionalised under a new operating company.
SureBuild, to the South African market. It
In 2013, PPC welcomed Ketso Gordhan
also introduced Botcem into the Botswana
as its new chief executive officer. Gordhan
market. In 2001, PPC acquired ownership
succeeds Paul Stuiver, who held the
of Portland Holdings Limited, Zimbabwe’s
position of CEO since 2009. Ketso brings a
leading cement company.
wealth and blend of experience in business
PPC also purchased the Mooiplaas dolomite quarry on the outskirts of Pretoria.
and in government, as well as knowledge of various industries.
Eerste Fabrieken Beperkt’s certificate of registration.
PRECAST VOLUME 7 • ISSUE 1 • 2013
12
article
accelerating this activity by increasing the usage of renewable fuels. The completion of a tyre recycling process will allow the group to reduce coal consumption at many of its kilns. The company is also committed to the procurement of at least 10% of its electrical energy from renewable sources. Recently, the Depar tment of Energy awarded a 60 MW wind-energy allocation to the Grassridge project in the Eastern C ape. T his pr ojec t, which is on a PPC proper ty, is aligned to a private wind farm development that will produce renewable power exclusively for PPC. Hercules Plant.
PPC: leading the market The enhanced PPC Surebuild, Unicem (Zimbabwe), Botcem
with better strength-
a 26% black ownership level within PPC
(Botswana) and Obras (Mo-
development properties.
South Africa. This achievement can be
zambique) products are all
Moreover, by adding more
attributed to the company’s commitment
extended or composite ce-
stone (aggregate) and sand,
to transformation and over eight senior
ments, engineered with lower
but the same amount of
black executives have been appointed
carbon footprints without
cement, 15% more concrete
with a special f ocus on black f emale
sacrificing performance. In
can be produced.
representation.
addition, the higher strength
In July 2012, PPC placed an additional
OPC and Surebuild require 15% less
PPC’s transformation
39.3m ordinary shares, equivalent to
cement for concrete production - thus
During the past couple of years, PPC
6.5% of the company’s increased share
lowering carbon footprints.
has progressed from a Level 7 Black
capital, under black ownership. The first
T hese recently improved products
Economic Empowerment (BEE) rating to
phase of the Broad Based Black Eco-
p r o v i d e c o n s t r u c t i o n p r o f e s si o n a l s
a Level 2 rating last year, when it reached
nomic Empowerment (BBBEE ) transaction for 15.3% was closed in 2008. The second phase will result in the increase of direct black ownership of the PPC Group to 20.8%. Of the additional shares being issued, 68% will be issued to employees of PPC’s South African businesses. Twenty seven percent will be issued to PPC’s existing strategic black partners (SBPs) and five percent to a newly created trust that will focus on black women in areas where the company operates. This transaction was structured for the benefit of those parties living in close proximity to the group’s businesses. Some 2 400 South African employees are participating and will own seven percent of the group. Setting the benchmark in
PPC’s expansion strategy.
PRECAST VOLUME 7 • ISSUE 1 • 2013
gender transformation The difference between a good company and
ARTICLE
13
a great one is its people. PPC recognises
group saw a 67% increase in its female
the broader industry. As a leader in this
the importance of attracting the country’s
employee ratio and a four-fold increase of
industry, and always at the forefront of
best to maintain its position as the leading
women in management roles. By the end of
innovation, the cement giant has actively
cement manufacturer in southern Africa.
last year, female employees represented
invested in technology to r educe air
The company believes emphatically that
20% of PPC’s total workforce.
emissions, minimise waste production,
by providing the opportunities, resources
PPC applies a learning-f or-gr ow th
r e c y cl e an d r e c o v er r a w m a t er ials,
and means, it enriches its employees and
principle across the group and has close
enhance energy efficiency and conserve
assists them in reaching their full potential.
to 10 academies and programmes in place
natural r esour ces while pr oducing a
To i n s t i l l f a i r t r e a t m e n t a c r o s s
– ranging from basic adult education and
reliable and affordable supply of building
gender, the cement manufacturer has
training, to graduate development and
materials to support the economies in
implemented various pr ocesses to
bursary initiatives for future engineers.
countries where it operates.
ensure that it attracts more females to
To attract f emales to the in-f ield
As a proudly African cement company,
this once male dominated industry. The
work, PPC provides a mining academy
PPC will continue to grow as a leading
company further aims to develop and
on a rock-breaking opencast quarrying
emerging-market business. The company
nurture its existing female employees’
qualif ication, which is r ated at NQF
currently operates in emerging markets,
skills and talent.
Level 3. Breaking old barriers in this
and all its adjoining territories are in
In 2011, the company launched the PPC
field is Norma Dyanti, based at PPC
emerging markets. Importantly, 70% of
Women’s Forum which aims to attract,
L im e A c r e s i n N o r t h e r n C a p e . S h e
the world’s cement is produced in these
nur ture and advance women’s talent
progressed from an operator support
markets. Emerging markets continually
to lead PPC. It is also a platform where
role to achieving a blasting certificate.
present new opportunities, higher growth
creativity and innovation is encouraged. Over the last decade, the number of female employees has expanded, and the
in populations, GDP and cement demand, PPC’s vision for the future
and deliver higher returns for producers
PPC’s focus extends beyond the group, to
of cement and related products.
P
EROSION PROTECTION SOLUTIONS
erosion protection paving
precast products concrete masonry drainage
kerbs
retaining walls
An engineered erosion solution that can withstand even the most severe climatic conditions. • Armorflex offers environmental protection • Labour intensive and cost effective • Complete erosion protection (even when placed under water) Tel: 0861266267 www.technicrete.co.za
Š All rights reserved
THE WORLD OF PRECAST CONCRETE CMA proudly presents phase one of the World of Precast Concrete which introduces the precast city. These maps will be made available to members and potential clients in print and electronic format. In the electronic version, one will be able to zoom in and click on various points which will be linked to members’ websites.
www.cma.org.za
For more information contact the 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
16
ARTICLE
A close up of one of the concrete block paved roads in Klapmuts.
CONCRETE BLOCK PAVING AND PRECAST USED EXTENSIVELY IN KLAPMUTS HOUS Very wet winters, a high water table and unstable sub-grade material (earth) has necessitated approximately half a 24 000m² road-building and access-course project in Klapmuts, Western Cape, to be surfaced with concrete block paving (CBP) because of its superior strength and stability properties. Asphalt was only used where the water table was deemed low enough and the sub-grade sufficiently stable by the main contractors, Power Construction.
some 11 000m² with CBP, 6 600m² of
The road-building project forms part of a
concrete block paving was deployed in the
turnkey housing contract which is being
sections where the sub-grade was unstable.
access course and 4 400m² of roads. Asphalt was only used where the subgrade was considered sufficiently stable. Steven Levey, senior quantity surveyor at Power Construction, said that the contract includes a 10-year latent defect clause and this was the main reason why
financed by the Department of Human
“CBP pr ov ides a long-term pav ing
Settlements. It was awarded to Power
solution unlike asphalt, which under these
Construction in a tender process by the
conditions, would most likely have begun
Stellenbosch Municipality, for whom the
cracking within five years. Moreover, CBP
project is being undertaken.
surfaces are aesthetically pleasing and
It involves the construction of 1 067 x
can easily be lifted and replaced as new,
40m² subsidy houses in two phases over
for example, for the installation of electric
five-years. Phase 1 is being undertaken
cables, which often takes place after the
in two portions of which Phase 1A sees
roads have been laid.”
the construction of 480 houses, due for
Power Construction’s contracts manager,
completion by the end of March this year.
Pietre Smit says that grey 60mm and
Designed by BKS Consulting Engineers
80mm 35MPa inter lock ing concr e te
and built by Seymour Paving, the road and access-course project involved surfacing
PRECAST VOLUME 7 • ISSUE 1 • 2013
A recently constructed concrete block paved road in Klapmuts.
paving blocks were used for the CBP. They were supplied by Concrete Manufacturers
ARTICLE
One of the precast concrete staircases being used in the construction of the double-storey units at Kalpmuts.
PRECAST CONCRETE SING PROJECT
17
Some of the hollow-core slabs which were used on the double-storey units at Klapmuts.
masonry; precast hollow-core slabs for
greater sense of community among the
second-storey flooring of the double-storey
lucky few who qualify for these houses.
units and precast staircases, supplied by
Another plus was the fact that that
Cape Concrete; and concrete roof tiles
much of the labour for the project was
supplied by CMA member, Eagle Roof Tiles.
drawn from the local community. Many
“Hollow-core slab flooring is ideal for
of them wer e unsk illed and r ecei ved
multi-storey structures, not only for
CE TA-accredited training from Power
Association (CMA) member, C.E.L. Paving.
subsidy housing, but for designer homes,
Construction,” concluded Armstrong.
“We laid the paving on a G4 base which
hotels, apartment and office buildings as
is superior to a sub-base and can easily
well. It’s a much faster and cleaner building
withstand the high water table. Moreover, it
process than in-situ flooring, and because
has good load-bearing capacity,” said Smit.
it’s produced in a factory environment,
Seymour Paving director, Jon Whiting,
offers high and consistent quality.
said the borders of both the access
“Similarly, precast staircases provide
courses and the roads were edged with
an e x c e ll e n t b uil ding s o lu ti o n . T h e y
double-cobble pavers (see photo), which
are much easier to install than their
were also supplied by C.E.L. Paving.
steel or timber equivalents and require
“It finishes off the project very neatly,” said Whiting,” and we have used the process extensively on other projects.”
no maintenance.” The largest precast component of the
One of the concrete block paved roads in Klapmuts which clearly shows the neat finish of double-cobble edging.
Klapmuts project was the masonry which
CMA executive director, Wally Arm-
comprised concrete blocks in three sizes
strong, says this Klapmuts subsidy housing
400mm x 200m x 190mm, 400mm x
project, which was NHBRC approved, is an
200mm x 140mm and 400mm x 200mm
excellent showcase for precast concrete.
x 90mm. Once built, the outer walls were
‘Not only was CBP chosen for the roads
plastered and painted and the inner-walls
because of its superior durability and all-
P
were bag-washed.
weather properties, but precast concrete
“Given the superior aesthetic pro-
formed the main building components in
perties of CBP and concrete roof tiles
the construction of the houses. These
has meant that the Klapmuts project is
included: precast building blocks supplied
visually appealing, and as such, is likely
by CMA member, Boland Concrete for the
to encourage pride-of-ownership and a
A concrete block paved road at Klapmuts under construction.
PRECAST VOLUME 7 • ISSUE 1 • 2013
18
applications
All materials used in scaffold construc-
safer SCAFFOLDing NEEDED – MBA
tion must be inspected for conformity with
A recent scaffolding accident, which left
design is prepared so that it can safely
the structure will be built must also be
one person dead and 19 injured after heavy
withstand the load it will hold as well as
inspected. Scaffold structures may only be
winds overturned the framework, has
vertical and horizontal wind pressures.
constructed by trained, competent scaffold
highlighted the need for strict adherence
Any scaffolding that does not fall into one
erectors under the direction of a supervisor.
to standards regarding correct scaffolding
of these categories must be designed by a
Supervisors must possess the necessary
design and construction. Deon Bester,
scaffold designer or professional engineer.
qualifications from an accredited training
required standards. The area on which
occupational health and safety manager
provider and approved by the South African
at the Master Builders Association (MBA)
Qualifications Authority (SAQA). They must
of the Western Cape, shares his expert
also comply with the legal construction
advice on how to prevent accidents like
regulations as well as those contained in
this from happening in future.
the SANS Code. Moreover, all scaffold erec-
The design and construction of any
tors must have undergone the requisite 18
steel tubular scaffold must comply with
months of classroom and practical training.
the South African National Standards
Once the structure has been built, it
( S A NS ) C o d e 10 0 8 5. T his c o n t ain s
must be inspected and declared fit for
requirements for design, maintenance,
use. No untrained people are allowed to
inspection, safety precautions and usage.
alter or remove items from existing safe-
To erect scaffolding that conforms to the
scaffold structures as the removal of
standards contained within the Code,
one component would render the entire
there are a few aspects which need to be
scaffold structure unsafe.
taken into consideration. These include
If the scaf folding is enclosed with
the condition of the surface on which
sheeting, shade netting or advertising
the scaffold is to be built, and the loads,
banners, this must be investigated and
weather and the wind pressures to which
approved before use since it could affect
it could be subjected.
wind loading. The scaffolding needs to be checked once a week, especially after
Scaffolding is divided into four specific
inclement weather or alterations, with
categories, based on the weight it is able to bear safely. The type of scaffolding required must be determined before a
Strict adherence to standards regarding correct scaffolding design and construction is essential for ensuring the safety of contractor employees and the public.
the details of these inspections recorded in a register.
AFRISAM RE-ENGINEERS CEMENT PORTFOLIO AfriSam has revised its entire product
said Neser. “We are particularly proud
All Purpose Cement is that it achieves
portfolio.
to have achieved the ‘R’ rating while
the equivalent seven day strength re-
A f r i S a m’s c o mm e r c i a l e x e c u t i v e,
retaining an ex tremely low carbon
quired from the old 32.5N class within
Grant Neser, says: “The revised product
footprint. We’ve effectively introduced
only 2 days.
line delivers ef fective, fit-for-purpose
technological advances that have boosted
Neser says AfriSam’s popular Eco
cements. This is the first time the company
the strength, durability, workability and
Building Cement has a carbon footprint
has introduced product improvements
performance associated with advanced
less than half the world average f or
across its full range on such a broad scale
composite cements, without sacrificing
cement and has now changed from the
- and more is to come.
sustainability.
32.5N to the 42.5N strength class.
“Over the years, AfriSam has made
“By moving to the ‘R’ class, we are now
“This is a true construction grade
a considerable investment in the
able to offer 15% more concrete which is
cement,” say s Neser, “which means
de v elopment o f ad v anced composi te
becoming the norm for leading brands.”
that it can be used in both construction
cements. The new line-up reflects our
Engineered as an all-round general
and general building applications. It has
commitment to delivering superior value
purpose cement for concrete, mortar,
the ability to produce high-performance
and to environmental responsibility.
plaster and screed applications, AfriSam’s
concrete with strengths as high as 60
“Our pr emium br and, A ll P ur pose
All Purpose Cement is spearheading the
MPa easily achieved. It is ideally positioned
Cement, has now been upgraded from
launch of its revised product portfolio.
for use in concrete, mortar and plaster
the 32.5N to the 32.5R strength class,”
An important feature of the new 32.5R
applications for Green buildings.”
PRECAST VOLUME 7 • ISSUE 1 • 2013
OUR DOOR
IS OPEN BECOME PART OF THE FUTURE
WE INVITE ALL PRECAST CONCRETE MANUFACTURERS TO JOIN US *
www.cma.org.za
* TERMS AND CONDITIONS APPLY
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
APPLICATIONS
21
A paved road in Chatsworth.
CHATSWORTH PRECAST CONCRETE PAVERS GOING STRONG 48 YEARS ON C
These precast Concrete Block Pavers
M rights to manufacture the S.F. block paver
(CBP) were laid 48 years ago in
south of the equator.
Y
Chatsworth, Durban and according to
Shortly after Hall’s return, the annual
Concrete Manufacturers Association
brick road tender was issued by Durban
(CMA) president, Taco Voogt, they look
MY Municipality, and Hall placed a provisional
good for at least another half century.
CY order for an S.F. Roadstone CBP machine.
When they reach the 50 year mark they will
He then tendered against a clay brick CMY
have provided twice the length of service
manufacturer and won the paving award
expected from a good tarmac road.
for Chatsworth.
CM
K
What is more, the roads have been
This led to the installation of a CBP plant
essentially maintenance-free, unlike their
in Chatsworth by German fitters, and the
asphalt equivalent installed in Chatsworth
production of S .F. pavers to a minimum
around the same time. The little upkeep
strength of 5 000psi (±35MPa) – the
that has taken place was not the result
prevailing German standard - commenced.
of surface failure, but was due to the
Strict control of aggregate grading and mix
installation and repair of water pipes and
design, personally handled by Hall, meant
electric cables which run under the roads.
that the quality and crushing strength of
Moreover, pockets of heaving clay were
the pavers was very high. On completion of
subsequently encountered, a condition
the contract in 1967 the machinery was
in which tarmac cracks and breaks up. In
relocated to Hume Pipe Co in Pinetown.
the case of Chatsworth’s CBP roads, the
Voogt adds that good bedding material
pavers were simply lifted and relaid after
and sub-base engineering also played a
the clay had been replaced with sabunga
substantial role.
(compacted stone and sand).
“This project proves quite emphatically
The project was initiated and con-
what the CMA has been promoting for the
trolled by Derek Hall, Pr.Eng. who says it
past 30 years, namely that CBP is an ideal
was the first of its kind in Africa south of
surface material for suburban and town-
the equator.
ship roads. Besides offering exceptional
Der ek discover ed concr ete block
maintenance-free performance, CBP is
paving technology during a business trip
also labour intensive, creates employment
to Germany in 1964 when he was general
and skills the unemployed, and therefore
manager of Hume Rhodesia Co. He visited
is ideally suited to the Government’s Ex-
the headquarters of the S.F.Roadstone
panded Public Works Programme (EPWP),”
Co in Bremen and negotiated the African
advises Voogt.
PRECAST VOLUME 7 • ISSUE 1 • 2013
22
APPLICATIONS
ARMORFLEX LINING PROTECTS EMBANKMENTS AT SILICA MINE Technicrete has supplied Ansaki Construc-
cabling to from a mattress-like finish which
tion with its Armorflex 180 erosion control
can withstand high-water velocities and
system to line embankments at Silica Mine
wave attack.
in Polokwane.
Mats in alternative sizes and weights
Ansaki’s Adriaan Willems said “We
can be produced for special applications.
required a lining that offered superior
Armorflex can be installed around rocks and
anti-erosion properties, facilitated easy
boulders and is not damaged by the constant
water flows and maintained the integrity
influx of debris into a channel or onto an
of the subgrade.
embankment. The blocks’ tapered design
“A r m o r f l e x 18 0 i s s p e c i f i c a l l y
reduces stress, provides mat flexibility and
designed for this kind of project. The
prevents slippage. If settlement occurs
embankment had a slope of +- 24-26º and
after installation, Armorflex merely adjusts
8 000m2 of Armorflex 180 was used to line
to the new contours.
and protect it.”
The water resistance, durability and
As seen here Armoglex can easily be applied around the rocks.
Armorflex can be supplied as loose
strength of Armorflex can be seen at
usually tied together with a polyrene rope,
blocks on pallets for manual installation,
Alberton/Natalspruit where an Armorflex
whereas 3.15mm diameter galvanized mild
or in preformed mats for mechanical
lining c o n s t r u c t e d 3 0 y e ar s ag o is
steel wire is used for manual installations.
inst alla tion. T he uni f or m blo ck s ar e
performing well.
In all applications a vertical bending radius
interlocked both mechanically and with
Factory-assembled, Armorflex mats are
of 0.5 metre is achievable.
APPLICATIONS
23
CHRYSO PRODUCTS IDEAL FOR PRECAST CONCRETE WIND TURBINEs T he use of precast concrete as a
and it produces epoxies for the moulds used
construction material for wind-turbine
to manufacture the blades.
p o w e r - g e n e r a ti o n t o w e r s is o n th e
Wind turbines must be able to perform
increase. As the towers reach new heights
in harsh environments and that is why
to support higher-powered, longer-bladed
durability is a vital requirement for the
turbines, the need for greater structural
concrete mixes.
strength to cope with the turbine weights and bending forces is also increasing.
“P l a s t i c s h r i n k a g e c r a c k i n g a n d settlement cracking can penetrate the
This calls for tower segments with
full depth of a slab/precast unit, requiring
larger cross-sectional diameters. Precast
expensive remedial measures and even
concrete is ideally suited for this application
greater cost should the slab/precast
as it can be produced with portable concrete
element have to be replaced. ChrysoFibres
batch plants on site. Precast concrete has
form a three dimensional bond with the
an added benefit of job creation, especially
concrete matrix and prevents early micro
in some isolated communities where the
cracks from widening into serious, slab
turbines are installed.
threatening cracks,” Correia adds.
Chryso’s Fluid Premia range of super-
I v or B o dding t on, a .b .e .’s p r o du c t
plasticers play a vital role in the manufacture
manager: Concrete Repair and General
of precast-concrete elements for turbine-
Construction, says another key wind-
tower construction. The molecules in its
turbine durability issue is ensuring that
Premia range are highly effective water
reinforcement is covered with sufficient
reducers, of fer workability retention
concrete. “With insuf ficient concrete
between 30 and 45 minutes, and achieve
cover, the reinforcement may corrode –
high early strengths. This allows for fast
causing spalling and structural failure.
construction and helps offset demanding
a.b.e. has two remedies for this: silocoat
fatigue loads.
and duracoat. Silocoat is a cementitious
“T he Chryso Fluid Premia range is ideal for maintaining consistency in the
coating equivalent to 180 mm of concrete,” Boddington explains.
manu f ac tur e o f r einf or ced concr e te components,” says Eddie Correia, Chryso GM: Technical Ser v ices. “It r educes sensi ti v i t y to changes in aggr ega te moisture or production batch tolerances.” The average concrete wind turbine tower comprises 18 precast 1,8m high segments with diameters ranging between 600mm and two metres. Chryso demoulding oils facilitate the easy stripping of wind-turbine moulds, reduce labour costs and preserve moulds. “Most importantly, the demoulding oils play a huge role in creating a defect-free surface finish with consistent colour. Moreover, they allow for casting immediately after oiling, unlike older demoulding oils which require a standing period,” Correia adds. Another member of the Chryso Southern Africa Group, a.b.e. Construction Chemicals, supplies an extensive range of adhesives to cater for specific strengths
An onshore wind turbine in which precast concrete was used for both foundations and tower segments.
PRECAST VOLUME 7 • ISSUE 1 • 2013
APPLICATIONS
25
LAFARGE’S CEM II AIMED AT PRECAST CONCRETE PRODUCERS L afarge South Africa phased out its
product under steam or heat curing. In
last CEM I cement pr oduct in 2009
addition, the general attributes of a quality
with the introduction of the innovative
cement formulated with siliceous fly ash
Rapidcem CEM II 52,5N. A first for South
are especially relevant to the manufacture
Africa, Lafarge’s CEM II Rapidcem cement
of precast concrete products. These are:
formulation was developed in consultation
• Enhanced concrete workability, making
with precast concrete and construction
professionals to meet the demanding
moulds
needs of the industry. The company now
• Reduced water demand for given slump,
offers the local market a complete range
improving the water-to-binder ratio and
of high-quality new-generation cements, all
increasing ultimate compressive strength
extended with siliceous fly ash.
• Better cohesion, producing castings
Precast-concrete products such as roof
it easier to place concrete in precast
with more unif orm proper ties and
tiles, pre-stressed railway sleepers, pipes
appearance
and culverts, have to be tightly controlled
• Lower heat of hydration, reducing the
for consistent quality and appearance,
and their raw material specifications
• Enhanced impermeability and a denser M
are correspondingly stringent. Lafarge
South Africa recognised that established
• Better response to heat or steam curing
risk of cracking more durable hardened concrete
C
Y
CM
CEM I users would be extremely cautious
due to the activation of the pozzolanic
abou t sw i tching to a new, mar kedl y
MY reaction in fly ash, giving higher early
different product. Consequently, Rapidcem
age strength gain as well as improved CY
was developed by the company’s Quality
late strength.
CMY
Department Southern Africa (QDSA) to
At the time of Rapidcem’s launch in
offer performance advantages in addition
2009, the South Africa’s environmental
to the consistent quality associated with
control legislation was not as advanced
Lafarge products.
as Europe’s. The lower carbon footprint
K
Rapidcem achieves a superior
of Rapidcem and the rest of the Lafarge
per formance in areas traditionally
c emen t pr o duc t r ange w as no t the
associated with CEM I products. It meets
key selling f eatur e. However, today,
and exceeds the precast industry’s high
the environmental merits of Lafarge’s
early strength requirements at 24 hours
innovative approach to cement design are
and 2 days, while performing equal to or
being appreciated.
better than any other CEM I 52,5 N or R
T he f ac t tha t Rapidcem’s mar ke t acceptance was achieved so successfully was well illustrated when Rail2Rail awarded a five-year cement contract to Lafarge for the production of a significant portion of the country’s concrete rail sleepers. After a demanding specialised testing programme and on-site trials, Rapidcem met the exacting German specifications and outperformed competition from CEM I products. A new manufacturer of prestressed railway sleepers, GPT, is also making use of Rapidcem. Lafarge South Africa endeavours to ensure the benefits of its technology are available to all its customers, both large
Rapidcem precast concrete rail sleepers.
and small.
PRECAST VOLUME 7 • ISSUE 1 • 2013
applications
27
Retaining walls offer varied form and function Kanonberg Lifestyle Estate consists of 31 hectares situated at the foothills of Cape Town’s Tygerberg, flanked by the exclusive Welgedacht Estate to the south and the Tygerberg Nature Reserve to the west. The 150 freehold stands in this estate range from 730 to 3 000 square metres, complemented by open spaces and walking trails. Excavated space for a new house had to be retained to prevent soil erosion. To avoid the wall from becoming too steep and exceeding height restrictions, main c on tr ac t or, D e c or t on, designe d the
A retaining wall at Kanonberg Lifestyle Estate.
walls for the top and the bottom of the property using Terraforce L12 rockface
blocks, plants were established to create
and demonstrates an ability to combine
segmental concrete retaining block (crb).
sof tness and tex ture between the
form with function, while also providing
The crb wall was designed with several
concrete blocks. Terraforce 4x4 Multi-
th e n e c e ssar y er o sion c on tr ol, an d
terraces to accommodate a small golf
Step blocks were incorporated to provide
maintaining good visual aesthetics that
green, outdoor patio, trampoline and
comfortable access to the different levels.
will continue to improve in tandem with
sandpit. At all levels and inside most
The wall was completed in April 2012
plant growth.
28
CMA members
Producer members company name
telephone
PROVINCE
telephone
PROVINCE
A Fick Sementwerke
(022) 913 1921
WC
PB
Kwena Brickforce
(00267) 392 2850
BOTS
PB/PI
Bass Beams
(031) 784 1920
KZN
PB
Lategan Cement
(021) 873 1154
WC
PB
Bay Brick
(035) 792 5218
KZN
PB
Marley Roofing
(011) 316 2121
JHB
PB
Beta Tiles
002634 2925303 002634 333422
ZIM
PB
Mobicast
(044) 874 2268
WC
PB/PI
Boland Concrete
(021) 875 5365
KC
PB
MVA Bricks
(012) 386 0050
JHB
PI
Bosun Brick Midrand
(011) 310 1176
JHB
PB
ReMacon
(011) 393 5504
JHB
PI
Brickcast
(031) 507 5525
KZN
PI
Revelstone
(0861) 173 835
WC
PB
0026 244 2107/8
BOTS
PB/PI
Reya Pele Bricks
(016) 363 0340
JHB
PB
C.E.L. Paving Products
(021) 905 5998
WC
PI
Rocla
(011) 670 7600
JHB
PB/PI
Cape Brick
(021) 511 2006
WC
PB
Salberg
(011) 357 7600
JHB
PB/PI
Cast Industries
(011) 316 2375
JHB
PB/PI
(041) 372 1933/372
EL
PB
Colonial Stone
(011) 794 9737
JHB
PB/PI
(011) 914 8500
JHB
PB/PI
Concrete Units
(021) 386 1923 (016) 3622236
WC/JHB
PB/PI
Style Decor
087 941 3889 071 744 2091
JHB
PB/PI
Conframat
(0861) 33 5599
JHB
PB/PI
Technicrete
(011) 674 6900
JHB
PB/PI
Corobrik
(031) 560 3111
KZN
PI
Topfloor
(021) 951 7700
WC
PB
Coverland/Monier
(011) 222 7300
JHB
PB
00263 04 746955
BOTS
PB/PI
Vanstone
(012) 541 2056
JHB
PI
Deranco Blocks
(041) 463 3338
EL
PB/PI West End Clay Bricks
(011) 851 1098
JHB
PI
Eagle Roof Tiles
(044) 874 0290
EL
PB
Echo Prestress
(011) 589 8800
JHB
PB
(00267) 71 321528
BOTS
PB
Inca Concrete Products
(021) 904 1620
WC
PB/PI
Inca Masonry (Garden Architecture)
(043) 745 1215
EL
PB/PI
Infraset
(011) 876 5100
JHB
PB/PI
Kavango Block & Brick
(021) 856 5213
NAM
PB/PI
082 850 3512 082 442 2082
JHB
PI
Brickbuild T/as Panda
Fastdeck
Keystone Walling
PRECAST VOLUME 7 • ISSUE 1 • 2013
company name
Shukuma Flooring Southern Pipe Contractors
Vaka Concrete
CONTRACTOR members company name
telephone
Decoroton Retaining System
(021) 875 5155
WC
Friction Retaining Structure
(011) 608 4321
JHB
Kalode Construction
(011) 781 3814
JHB
PYW Paving
(031) 903 1736
KZN
Roadstone Civil &Paving
(011) 683 7080
JHB
S A Paving
(011) 483 1350
JHB
CMA MEMBERS
29
Associate Members company name
telephone
ARQ Consulting Engineers
(012) 348 6668
JHB
ILIFA Africa Engineers
(016) 981 0591
JHB
JC Paving
(011) 431 0727 079 884 7986
JHB
Pipes
(012) 644 0043
JHB
Sekhukhune & Associates
(012) 993 4776
JHB
SNA Civils & Development
(012) 842 0000
JHB
Terraforce Pty Ltd
(021) 465 1907
WC
Young & Satharia Consulting Civil Eng
(031) 207 7252
KZN
non-producer members company name
telephone
Able Equipment
(044) 874 1876
EL
Ash Resources Pty Ltd
(011) 886 6200
JHB
Birkenmayer H Pty Ltd
(011) 970 3880
JHB
BASF Construction Chemicals
(011) 203 2400
JHB
Chryso Southern Africa
(011) 395 9700
JHB
Kaytech Consulting cc
(031) 717 2300
KZN
Kerneos Southern Africa
(011) 444 3090
JHB
00 31 113 562 460
NETH
Manitou SA Pty Ltd
(011) 975 7770
JHB
Mapei
(011) 552 8476
JHB
Pan Mixers SA Pty Ltd
(011) 397 3754
JHB
(0049) 7391 5050 148
GER
SIKA South Africa
(031) 792 6500
KZN
Soilab Pty Ltd
(021) 988 7410
WC
Smartstone Pty Ltd
(011) 310 1161
JHB
Technical Finishes
(021) 535 4455
WC
Techmatik SA
+48 483690811
POL
Kobra Moulds B.V.
Rampf Formen GmbH
cement members company name PPC Cement Pty Ltd (JHB H.O)
telephone (011) 386 9000
JHB
PRECAST VOLUME 7 • ISSUE 1 • 2013