Precast • Issue 1 • 2020 by Isikhova Media

ISSUE ONE • 2020

R49,00

THE VOICE OF THE PRECAST CONCRETE INDUSTRY

INDUSTRY ASSOCIATIONS ENSURING QUALITY AND CONSISTENCY - Industry representation and formalisation - Driving standards higher - Providing effective certification services

• Academic laboratory coming • Concrete is greener • JHB highway deck repair

Premium cement for precast products SURECAST FOR EARLY STRENGTH PERFORMANCE

SURECAST is a premium performance product that provides consistent, economical high-early strength where early handling is required. USED FOR: Precast concrete products, structural reinforced and pretested concrete, paving, grouts and shotcrete as well as bricks and blocks.

Please contact: 0800 236 368 www.ppc.africa

TECHNICAL

2 A WORD ON INDUSTRY ASSOCIATION MEMBERSHIPS

15 USAGE PHASE OF CONCRETE IS GREENER 16 CONCRETE OFFERS SUPERIOR STRUCTURAL INTEGRIT Y

INDUSTRY NEWS 4

27 PRODUCT OFF-PACKING SYSTEMS

PRECAST WALLING IS THE SAFEST OPTION

COMPANY NEWS 17 CONTRIBUTING TO SPORTS DEVELOPMENT 18 NEW LABORATORY PROVIDING SOLUTIONS 19 AWARD FOR TOILET DESIGN

5 6

SOCIAL MEDIA SOLUTIONS FOR THE PRECAST INDUSTRY

BUILDING A RISK-READY CONSTRUCTION INDUSTRY

PICP - A CASE FOR REGULAR PERFORMANCE TESTING AND MAINTENANCE

28 GREENER AGGREGATES FOR CONCRETE 29 ADVANTAGES OF CONCRETE PARKING AREAS

GLOBAL VIEW

PROJECTS 32 CUSTOM-MADE PAVERS REVITALISE PEDESTRIAN WALKWAY IN CAPE TOWN

PRODUCTS

33 JOHANNESBURG TWIN-DECK HIGHWAY BRIDGE REPAIR

21 VERSATILE PRECAST CONCRETE EQUIPMENT SHELTERS 22 SETTING UP AN EFFICIENT WALL PRODUCTION LINE 24 THE RIGHT PRODUCT FOR THE JOB 25 ART AT THE LEONARDO

11 THE REAL THREAT OF USING SUB-STANDARD CEMENT 13 QUARRIES ESSENTIAL TO A SUSTAINABLE CONSTRUCTION INDUSTRY

14 CONCRETE PIPING PROVIDES UNMATCHED DURABILIT Y

PRECAST is the mouthpiece for the Concrete Manufacturers’ Association - CMA Concrete Manufacturers’ Association Physical Address: Office 0400, Standard Plaza Building, 440 Hilda St, Hatfield, Pretoria Postal Address: Post Net Suite 334 Private Bag X 15, Menlo Park, 0102 Tel: (+27 11) 805 6742 Fax: (+27) 86 524 9216 E-mail: admin@cma.org.za Website: www.cma.org.za Publishers: Isikhova Media Address: 10th Floor, Metalbox, 25 Owl Street, Milpark, South Africa Tel: (+27 11) 883 4627 Fax: (+27 11) 783 2677 Website: www.isikhova.co.za Publisher: Imraan Mahomed Tel: (+27 11) 883 4627 E-mail: imraanm@isikhova.co.za Consulting editor: Raymond Campling Tel: 076 297 2775 E-mail: media@mediasavvy.biz

PRECAST | ISSUE ONE | 2020

30 SA ARCHITECTURE SHAPES UP WITH DECORATIVE TILT-UP CONCRETE

20 SOLUTIONS FOR THE PRECAST INDUSTRY

35 CAST-STONE COBBLES COMPLEMENT NEW CENTURY CIT Y PARKADE 36 PRECAST FACILITATES SHOPPING MALL OVER BUSY RAILWAY LINE

Coastal editorial: David Beer Tel: 082 880 6726 E-mail: david.bigsky@gmail.com

ISSUE ONE • 2020

R49,00

THE VOICE OF THE PRECAST CONCRETE INDUSTRY

Subscriptions/Accounts/ Advertising: Thuli Majola Tel: (+27 11) 883 4627 E-mail: thuli@isikhova.co.za Design and layout: Joanne Brook E-mail: joanne@isikhova.co.za The views and statements expressed in this publication are not necessarily those of the editor or the publishers and neither the publishers nor the CMA accept responsibility for them. No person connected with the publication of this journal will be liable for any loss or damage sustained as a result of action following any statements or opinions expressed herein. The same applies to all advertising. Precast© 2020. All rights reserved. No part of this magazine may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage retrieval system, without prior written permission from the publishers. Endorsed by:

ON THE COVER The CMA works tirelessly to promote the use of quality precast

CONTENTS

GM’S NOTE

INDUSTRY ASSOCIATIONS ENSURING QUALITY AND CONSISTENCY - Industry representation and formalisation - Driving standards higher - Providing effective certification services

• Academic laboratory coming • Concrete is greener • JHB highway deck repair

concrete from its members. The association simultaneously represents the interests of the industry with far-reaching marketing campaigns, Government lobbying, the establishment of technical committees to assist with the setting of national standards, as well as the provision of certification services exclusively for the concrete industry. It also provides skills development workshops, reference books and a host of other services that makes CMA membership an essential tool for the country’s top precasters.

GM’S NOTE 2

A WORD ON INDUSTRY ASSOCIATION MEMBERSHIPS From beautifully paved spaces, stylish facades and attractive rooftiles, to effective barriers and concrete infrastructure, precast concrete can do it all. The cover photo shows how beautiful precast concrete makes our world with strong and durable materials that can last a lifetime.The industry is represented by a strong industry association that provides services and assistance to the precast manufacturers and should be a defacto source for all project developer and contractors to find precast concrete suppliers that are equipped to design, implement and reliably deliver products of the highest quality. In this article the Concrete Manufacturers Association (CMA) general manager, Henry Cockcroft, looks at the many benefits provided and why all precast concrete manufacturers should become members of the association.

cleared up matters of which the members did not even know. In doing so, it salvages business relationships and protects the industry against tainted perceptions. Did you know that your industry association speaks to: • government representatives gather

ing general product information?

• architects seeking prouct informa

tion and networking opportunities

with engineers?

• engineers seeking product informa

tion, installation solutions and guid-

ance with regard to industry support?

• other industry associations, ie the

NHBRC, CIDB and – believe it or not –

even the SA Banking Association in

To be or not be? That was the question

insurance. The subscriber will never see

terms of guarantees on the supply of

then! It seems that these days, the ques-

the full value of the service. In silence, the

quality precast concrete into the

tion should rather be: to belong or not to

industry association answers the phone

construction industry?

belong?

calls which never reach the member. The

• academics and students in pursuit of

This would bring us to the matter of

association will be asked the questions

ex tended k now ledge on pr ecast

industry representation bodies, industry

which the member is never asked. The

concrete and such solutions?

associations and professional societies.

industry association is seen as the

• satisfied and highly irate clients alike?

“prefect” of the schoolyard. If anything

• even the old “ tannie” who phoned

The silent partner

goes wrong, the parties with their gripes

and complained about her hydrangeas’

It is unf or tunate that association

run to the industry association. In many

concrete pot, which had cracked after

membership can be compared with life

cases, the industry association has

20 years?

PRECAST | ISSUE ONE | 2020

In many cases, we have seen that mar-

cost that much to maintain. Did you know

keting departments and sales teams do

that your industry association is highly

varying importance right through the

not have a clue about the industry asso-

qualified to do exactly this? Did you know

built environment. The comments always

ciation and the benefits allocated to that.

that your industry association carries

remain the same: “If you wanted qual-

To tickle the fancy and spark a bit

qualified representatives with the ability

ity precast concrete, you should have

of enthusiasm concerning industr y

to assist in quality management system

supported a Concrete Manufacturers’

association benefit offerings, we would

(QMS) design, implementation, mainte-

Association [CMA] producer member.”

like to mention the following.

nance and auditing? We can take another day to discuss

Leveraging benefits

A word about benefits

the values and benefits of QMSs and how

How would one, then, go to work in order

We were quite surprised! Contrary to

to design and implement them in various

to leverage benefit from industry asso-

all the advice of the powers that be in

sizes of businesses, but for the sake of

ciation membership? What can be done

our association, social media marketing

this article, we would like to consider the

to make this unseen benefit more visible

tur ned ou t to be way ou tside the

following: levelling the playing field in an

and even tangible? Two words come to

guidelines, expectations and experience,

extremely competitive market for equal

mind: communication and participation.

which all had a wealth of knowledge and

opportunity. Now, that’s a lot said! We

Communication, of course, is twofold:

recommendations on it. Having tried

are entering a phase in SA where focus

communication from the industry associ-

and tested two social media platforms,

is being increased on the requirements

ation to its members and communication

we can – through experience – clearly

of service, product supply and project

from the members back to the industry

comment on their effectiveness. Do not

completion. These elements of “business”

association. If the industry association

underestimate the influence of thousands

are shadowed by legal liability. What a

does not update, communicate and

of people having the privilege and leisure

fantastic opportunity is created by this

engage with its members, the members

to follow activities on Facebook. Whether

to level the industry playing field in terms

do not know what is transpiring.

one uses a social media platform for

of supplying product to the market con-

It is, however, a fact that the industry

professionals or a social media platform

sistent in quality and being in a position

association must also know what its

which is just “social”, it does not matter.

where one can document, trace, certify

members are doing. A re they busy

The point which is important is that the

and prove that quality consistency. Who

developing any new products? What good

industry association has now increased

better than the industry association to

projects have they been involved in? What

its reach to the market multiple times –

guide its members in the establishment

challenges do they face in the market?

and it is growing daily.

of methods and systems, in the form of a

Benefit does not only feature in the

QMS? This will ensure delivery of quality

dissemination of information and in the

precast concrete to the market and gen-

Effective communication assists in

achievement of one of the association’s

erate preference with regard to supply.

determining the value proposition of in-

major goals: “The promotion of precast

Creating and promoting a specific

dustry association membership. Having

concrete”, but also in the fact that

expectation with regard to consistency

said that, it is important to note that in

members can make use of the association’s

in quality of a product which is supplied to

times gone by, the association experi-

established a social media platforms and

the market will ultimately level the playing

enced a definite requirement for change

networks. We are all aware of the fact

field. Manufacturers of high-quality

in communication channels to the mem-

that print media, which still plays an

product will be identified and will be singled

ber. Historically, industry associations

important role, is extremely expensive.

out as suppliers of preference to the built

and their management communicated on

This places strain on budgets in trying

environment. The stakes in SA are slowly

executive and senior management levels

economic times. Why would anyone, then,

becoming too high to risk reputational

within the structures of their members,

shy away from this fantastic membership

damage by supplying inferior products.

mainly because this was the chamber for

benefit, if of fered the association’s

So, here is the final word: join your

decision. Today, however, in an environ-

membership package? A picture and a

industry association. Belong to your

ment marked by free enterprise for all,

paragraph on a regular basis are all which

industry group. Power is in numbers and

governance dictated by institutionalised

are required to make a good impression

this is the way we can influence our mar-

organisations, modernised electronic

on the market out there.

ket to the betterment of our industry.

Are there any specific needs with which the industry association can assist?

marketing platforms and extremely com-

Dreaded quality management sys-

Legions of advantages can be listed, but

petitive environment, the communication

tems! Dreaded 9001 implementation

we are of the opinion that the biggest one

channels to the members have changed

and audits! Time, resource and money

would be the image which is connected

– and if they have not changed yet, then

are what it requires! This, unfortunately,

to a business supporting the industry

they should! Full benefits and the lever-

carries truth to some extent. The fact

association. Association membership is

age of benefits offered by industry as-

remains that if you know the industry

synonym with quality, honesty, profes-

sociation membership will be experienced

and its processes and you know the re-

sionalism and a proper code of conduct.

when bi-directional communication exists

quirements of the quality management

between executive and senior manage-

system, you can streamline it to become

ment, the marketing department, the

a valuable tool in the business – which is

GM: CMA

sales team and the industry association.

not that time-consuming and does not

Director: CMA Certification Services

PRECAST | ISSUE ONE | 2020

Henry Cockcroft

GM’S NOTE

Your silent industry association is very well heard in various circles with

INDUSTRY NEWS

PRECAST WALLING IS THE SAFEST OPTION Precast walling is facing fierce opposition from new steel fencing systems that create a tough barrier, as well as providing occupants with almost unhindered views.

While these fencing systems provide buyers with far greater choices, they are not suitable for every application and, in most instances, simply cannot provide the same level of security that is offered by a solid concrete barrier. Melinda Esterhuizen, operations and marketing director of Echo, a preeminent supplier of hollow-core precast concrete walling, says that while some suppliers market the fencing as being as effective as concrete walling, it actually is not. No comparison “Where security is a priority, fencing simply can’t be compared with a 50MPa 150mm (thick) prestressed precast concrete wall. It provides both a visual and physical barrier that prevents wouldbe intruders from scoping the premises, as well as being able to withstand extreme punishment. “ I t ’s i m p o r t a n t t h a t p e o p l e understand the dif f erence. Steel

separate pedestrians and traffic from

plants, marshy areas, etc, where fences

railways and highways.

would probably eventually corrode.

fences are largely used in residential

“Due to their smooth surface, the

Precast walling systems in all shapes

or light industrial systems for low- to

walls can’t be climbed and the high-

and forms of fer versatile solutions

medium-security applications – unless

s tr eng th r ein f o r c e d c o n cr e t e w ill

that can last a lifetime. By its nature,

they’re supported by supplementary

withstand hammer blows and even

concrete is robust and strong, which

measures such as guards or control

vehicles being driven into it at speed.

adds an element of security that cannot

room-linked cameras. Our hollow-core

Since they’re up to 6m high, specialised

b e m a t c h e d . E c h o’s high - s e c ur i t y

concrete walls are used in high-security

equipment would be needed to either

prestressed hollow-core walling system

applications and provide barriers to

climb or penetrate the walls – and that

pr ovides rapid deployment and can

protect anything from military bases,

would take time and involve a considerable

secure even the highest-risk areas,

airports, telecoms, petrochemical and

amount of noise and effort.

which is a tougher act than any fence

gold refineries to providing barriers to

“Considering that one precast panel

can follow.

can be 5-6m long, 1,2m high and weigh about three tons, it can’t be manhandled

(Above and left): Precast walling systems.

and anyone wanting to smash their way through it would have to contend with two rows of 5mm triple-indented prestressed wire that can’t simply be bent or cut,” says Esterhuizen. Maintenance-free She adds that a pr ecast wall is a lifetime investment and does not require maintenance once erected, provided it is properly installed and founded. This is an important consideration wherever conditions conductive of corrosion exist,

Benefits of precast walling systems: - Rapid installation. - Wall heights are up to 6m. - Super-strong. - Effective barrier traffic and sound - Restricts visibility. - Lifetime investment. - Suitable for industrial and some residential estate applications.

such as coastal areas, certain industrial

PRECAST | ISSUE ONE | 2020

INDUSTRY NEWS

(Below): An aerial view of the University of Pretoria’s impressive new Engineering 4.0 building.

The University of Pretoria will become the env y o f academics ar ound the world when its ultra-modern national material reference laboratory, including an impressive concrete laboratory, is completed later this year. Engineering 4.0 is the fourth major

facility will also facilitate specific com-

WORLD-CLASS ACADEMIC LABORATORY NEARS COMPLETION

mercial testing for extreme or difficult

one of the largest in the academic world.

edge for the benefit of the entire civils

testing, especially where other laborato-

The facilities and equipment will have

community and when it opens its doors

ries do not have the required facilities.

“extraordinary” capabilities, including

on 1 March, it will allow co-operative

According to Prof Wynand Steyn, head

extreme temperatures and conditions,

research between disciplines and other

of the Department of Civil Engineering at

which will give the university’s post-

civils laboratories and will be part of the

the university, the decision to construct

graduate students the opportunity to un-

exciting Innovation Africa initiative.”

the facility follows talks with the SA

dertake focused and advanced research.

engineering building on the university’s premises and will serve as a research centre for materials used in the roadbuilding and construction industries. The

National Roads Agency Ltd (Sanral) over

It will also give trained engineers

the requirement for a roads reference

valuable exposure to material tests in

laboratory. Because the experimental

controlled laboratory environments and

area is situated between the university

provide suitable facilities to conduct

and the Council for Scientific & Industrial

duplicate testing for Sanral, as well as

Research premises, an agreement was

other local and international institutions.

signed between these parties to co-

Facilities for the training of concrete

operate in its development.

technologist are also on the cards.

Multi-purpose facility

a large part (5 500m² of the total

He adds that when completed, it will be

8 000m²) of the new building and will be

the largest facility of its type in SA and

fully equipped to handle under- and post-

The concrete laboratory takes up

graduate students with a preparation area, standard concrete testing apparatus, controlled curing facilities with four specialised curing rooms from 5-85˚C and 85-100˚C humidity and other equipment. Special floor “We’ve constructed a 1m-thick strong floor spanning 20m x 15m with precisely spaced connection points every halfmetre. This will allow for different configurations of jacks and other gear and give space for multiple projects to be accommodated simultaneously,” says Steyn.

“The facilities and equipment will have extraordinary capabilities, including extreme temperatures and conditions.”

“The facility will be a major benefit for our students, partners and the concrete industry as a whole. It will generate knowl-

PRECAST | ISSUE ONE | 2020

(Above and left): The precision strong floor required 300m³ of 65+MPa concrete, which was completed in two pours.

INDUSTRY NEWS 6

SOCIAL MEDIA SOLUTIONS FOR THE PRECAST INDUSTRY T he broader populace walk on their

contributed to dwindling investor con-

power ful solution that should be

feet, but live on their smartphones,

fidence and placed fiscal limitations

added to every construction com-

which begs the question whether the

on public expenditure.

pany’s marketing mix.

built environment is utilising digital

• Private sector – economically. In the

marketing in an effective manner that

first quarter of 2019, the economy

conversions in the market is shrinking,

fully harnesses the leverage of industry

saw a 0,8% drop in household con-

technology in the f orm of industr y

association influence.

sumption spending on a quarter-on-

association-driven social media marketing

The construction industry has func-

quarter basis that contributed to a

is enabling industry association members

tioned on the same principles of market-

0,5% contr action o f the over all

to gain valuable insights in order to

ing for the past few decades. Billboards,

G D P. T h e d e c l i n e i n c o n s u m e r

construction banners, word-of-mouth

Although the number of customer

better convert leads.

spending is attributed to household

Industry associations provide a rel-

and TV commercials were the

deb t, c o s t s o f ser v icing

evant and structured platform for the

“go-to” places to find poten-

the debt and access to

efficient marketing of various construc-

tial clients because the mar-

additional credit, which is

tion-related building materials, tech-

ket was conducive. But the

being exacerbated by poorer

nologies, supplementary products and

economic and technological

employment prospects.

equipment. With close co-operation and

landscape has changed and

Household income rose by

effective strategies, industry associa-

social media platforms such

0,6% in 2018 – which means

tion marketing places products in front

as the Concrete Manufactur-

that slow-rising disposable

of the target market through social me-

ers’ Association channels

income and high indebtedness

dia and increases online awareness of the

now offer more cost-effec-

do not leave much room for

brand involved. Industry associations are

tive and targeted solutions

consumer spending.

in possession of industry-related educa-

for the construction industry to remain

• Technology has grown in complexity

tional, technical and general information

informed. The statistics below are a grim

since it has been layered into research,

which can be leveraged to the benefit of

reflection on the state of the economy

design, finance and manufacturing. The

the members of the association.

and should serve to remind company

inception of social media also con-

T he r eal benef it of social media

heads that effective marketing will in

tributed sociologically to an immense

originates from the modern reliance on

future be critical to increasing revenue:

change in human social interaction.

social media networks to source quality

• Public sector – economically: SA’s

However, the sociological change

products and quality service, and to form

public infrastructure expenditure

also spread to the business sphere

opinions by reading reviews. Working

peaked in 2014/16 (approx R250 billion)

by providing a smorgasbord of new

with industry associations can mitigate

and the public-sector infrastructure

communication channels, as well as

the effects of the current economic

spending as a share of GDP has been

a new manner to facilitate business-

climate and help companies get more

steadily declining since 2009/10.

to-business and business-to-

bang for their marketing. In addition, it

State-owned enterprises have caused

customer marketing practices. As

strengthens the association and ben-

a drain in the Treasury Department,

a result, the linking of social media and

efits all its members.

with large amounts of money being

digital efforts with industry associ-

funneled into parastatals. This has

ation channels is becoming a new and

(Above left): Liandré Bezuidenhout of the CMA.

PRECAST | ISSUE ONE | 2020

INDUSTRY NEWS

The SA construction industry currently finds itself in an unpredictable macroen v ir onmen t, w i th Fi t ch Solu tions predicting sluggish growth of only 2,4% for 2019. Talk of a looming global recession is causing capital expenditure on largescale construction projects to dwindle,

sending the industry into a rally to achieve higher levels of risk-readiness to address increasing uncertainty.

18-24% due to risks facing the industry,”

BUILDING A RISK-READY CONSTRUCTION INDUSTRY

says Clarissa Rizzo, business unit manager

spectrum is bringing the pr oblems

involves the following:

for professional risks at Aon SA. “It’s

organisations face when they run into

• Reducing the total cost of a risk by

therefore no surprise that the construc-

capital availability problems into sharp

tion industry reported a 5% increase in

focus. Despite the fact that it is ranked

• Aligning strategic risk management

efforts deployed to increase the industry’s

as the third most pressing risk facing

activities with the risk management

risk-readiness, compared to two years.”

the construction industry, accounts

plan and overall strategic objectives

receivable is often the largest uninsured

of the organisation.

The top three risks facing the construc-

asset on a company’s balance sheet,

• Identifying best practices and applying

tion industry:

constraining cash flows.

“A on’s Glob al Risk Managemen t

Sur v ey sho w s tha t the c ons tr uction industry has experienced a massive increase in reported losses from

1. Economic slowdown/slow recovery

incorporating a value at risk metric.

them to the business.

• Identifying weak practices and taking

The construction industry considers

Mitigating the risk

the risk of an economic slowdown to be

Aon’s Global Risk Management Survey

• Performance benchmarking against

correctional steps.

its top concern. Businesses generally

found that 25% of respondents from the

peers.

tend to reduce or hold back on capital

construction industry have developed risk

“If we compare this year’s survey

expenditure when experiencing economic

management plans to address assessed

results with those of 2017, we see

strife, causing the growth of the industry

and quantified risks, while a further 15%

an overall increase in the proportion

to grind to a halt.

have evaluated risk finance or transfer

of organisations evaluating their risk

2. Cash flow/liquidity risk

solutions. An additional 14% of the

management programmes, with more

This refers to the possibility that an

industry put continuity plans in place.

companies lowering their total cost of

organisation could fail to obtain the cash

“It’s very encouraging to see that

risk [TCOR]. North America proved to be

required to meet short- or intermediate-

87% of respondents say they’ve adopted

the most developed region in this regard,

term obligations. According to CPA

either a formal or partially formal ap-

while the Middle East and Africa use the

Australia, liquidity risk can arise from a

proach to risk oversight and manage-

TCOR measurement proportionally less,”

number of scenarios within the business.

ment at board level, with all companies

says Rizzo.

These include unplanned reduction in

ranging from multi-nationals to SMEs

More organisations are embedding

revenue, business disruption, sustained

placing more importance on risk manage-

risk into the business and looking at ways

reduction in profitability, unplanned capital

ment than before,” says Rizzo.

of turning these challenges into business

expenditure, increase in operational

“The proof, however, is in the pudding,

opportunities. “Larger companies

costs, future debt repayments and

and the questions to ask are whether

are more likely to implement

breach of loan covenants.

their efforts have reduced the prob-

an ef fective risk manage-

3. Capital availability/credit risk

ability or the resulting impact of risks

ment programme than their

The failure of businesses across the

occurring, and how they performed

smaller counterparts, mak-

in comparison with past risk-

ing it crucial for the industry

“Looming global recession is causing capital expenditure on large-scale construction projects to dwindle.” PRECAST | ISSUE ONE | 2020

based incidents.”

– as a whole – to become

T he Aon Risk Maturity

aware of the risks fac-

Index Insight Report found

ing it and actively plan

that organisations with high-

to improve prepared-

er levels of risk maturity gen-

ness, resilience and

erally invest time and effort

sustainability.”

in reviewing the performance and effectiveness of their risk m an ag em en t p r o gr amm e . Measuring its effectiveness

(Left): Clarissa Rizzo, business unit manager for professional risks at Aon SA.

INDUSTRY NEWS 8

PICP - A CASE FOR REGULAR PERFORMANCE TESTING AND MAINTENANCE Permeable interlocking concrete paving

celerates the blocking process. As yet,

systems (PICP) established a tentative

it would appear that there is no local

toehold on the South African landscape 13

installation which has been properly

years ago. The first known system was in-

maintained, although the PICP system

stalled in 2007 at The Reeds, a townhouse

at Cape Town’s Blue Route Mall comes

complex in Fairlands, Johannesburg.

close. The results were inevitable; apart

As with all PICP systems worldwide,

from new installations, no South African

the prime objective – then as now – was

PICP installation is known to be operat-

the prevention of flooding through the

ing optimally and some – such as the

controlled discharge of stormwater into

parking lot at Cape Town’s Grand Parade

municipal drainage systems. This was

– are totally blocked. Now 10 years old,

to be achieved by creating a surface

the parking lot was constructed shortly

which facilitated stormwater infiltra-

before the 2010 Fifa World Cup.

tion, rather than run-off, as found in traditional impermeable paved surfaces.

Working group

With the introduction of Cape Town’s

Fortunately, this situation has been

Management of Urban Stormwater Im-

identified as a major problem by the

pacts Policy in 2009, PICP was quickly

University of Cape Town (UCT), which

adopted by local stormwater profes-

is tackling it head-on. Over the past

sionals to reduce the negative impact

year, Neil Armitage, deputy director:

of impermeable surfaces on equatic

“Future Water” and a professor in UCT’s

Sustainable solutions

ecosystems.

Department of Civil Engineering, has

“This lack of information as to how regular

been conducting research which aims

maintenance affects the longevity of PICP

Gaining traction

to improve the sustained performance

systems has been identified as a limiting

Notwithstanding dozens of installations

of all South African permeable paving

factor in improving the wider use and ac-

countrywide, PICP still has some way to

installations. He is being assisted by a

ceptance of PCIP. My research is intended

go before it can claim fail-safe status.

working group of professionals and civil

to contribute to the limited source mate-

It is hard to find a single installation

engineering students at UCT and some

rial on infiltration capability and testing

without some design flaw. These include

of their findings have been discussed in

methods of permeable pavement systems

the use of dirty aggregates, inappropri-

previous issues of Precast .

in the South African context and thereby

(Above): Measuring a SWIFT test wetted area.

ate use of geotextiles, pavers with poor

In this issue we take a brief look at

to promote sustainable counter-solutions

interlocking properties and the use of

some research on PICP performance

to conventional pavement designs which,

sand as the filler between pavers.

testing and maintenance aspects un-

in turn, will play a role in solving SA’s cur-

Then there is maintenance. Many

dertaken by one of Armitage’s students,

rent water management and shortage

property-owners appear to be unaware

Cole Barnard, for a thesis which forms

problems,” writes Barnard.

that PICP systems require maintenance,

part of his BSc in civil engineering.

He tested infiltration rates on seven

but regular removal of sand and other

Barnard asser ts that because

sites in greater Cape Town. Some of

debris from between the pavers to

PICP technology is still relatively new,

them had not been previously tested,

prevent blocking is essential to their

maintenance requirements have yet

while others had test results data dat-

proper functioning.

to be categorically established across

ing back to 2017. Only two sites were

the full range of installation types and

tested in Johannesburg, as most sys-

conditions.

tems were located in gated communities

C ap e To w n f ac e s the addi tional problem of windblown sand, which ac-

with restricted access. Barnard’s research involved testing the infiltration rates using the ASTM Single Ring Infiltrometer – the American standard – and the Stormwater Infiltration Field Test (SWIFT) method modified from its original Australian use. Although the Single Ring Infiltrometer test, which measures actual infiltration

(Left): Water is discharged from a bucket during a SWIFT test.

PRECAST | ISSUE ONE | 2020

rates, is the “gold-plate” standard, it

may be exacerbated by local conditions.

is impractical, as it is time-intensive.

The ultimate objective of Barnard’s

Therefore, part of his research entailed

research was to assist in the creation

establishing a corr elation between

of industry guidelines for the construc-

the ASTM and a modified SWIFT test,

tion and maintenance of PICP systems,

which – as its name implies – yields much

thereby encouraging more use of PICP

quicker results than the ASTM Infiltrom-

systems, their better care and im-

eter test. The rationale behind this was

proved lifespans.

to give PICP owners and researchers a

His research led to several conclu-

reliable method to establish infiltration

sions. He established that, provided they

rates with equipment that is easy and

are installed correctly using the specified

inexpensive to use.

codes, PICP systems are efficient stormwater management systems. They are

Testing required

able to perform at higher-than-average

The original SWIFT test is based on the

drainage capability when properly main-

number of fully wetted bricks resulting

tained and can also perform at accept-

from discharging six litres of water from

able drainage capability for a while, even

an elevated bucket onto the PICP pavers. Barnard found counting the number of wetted bricks to be excessively timeintensive. Instead, he measured the length and breadth of the wetted surface and appr oximated its ar ea by using the formula for an ellipse. The best-fit curve between the approx-

when they are not

“SA needs an overarching governing design code to ensure permeable paving systems are designed and installed correctly.”

imated wetted area

properly maintained. However, unless deterioration is monitored regularly, full blockage and hence unanticipated flooding can occur on site. Limiting debris Barnard also found a reasonably accurate relationship between wetted areas and infiltration rates. This facilitates the rapid

and the infiltration rate was found to be:

estimation of the latter, which makes it

I = 1958 – 1 056In( A )

easier to determine how a PICP system

Where:

is performing and thereby the required

I = infiltration rate (mm/hr)

maintenance frequency.

A = π (a x b) / 4 = wetted area approxi-

Barnard believes that PICP site-

mated by an ellipse (m²)

owners should investigate means of

a = longest wetted length (m)

limiting debris – for instance, by prefer-

b = wetted length perpendicular to a (m)

ring evergreen to deciduous trees and

Infiltration data was collected from

the use of retaining walls for flower beds

each site and evaluated against the

to prevent the deposition of soil on the

catchment area which the PICP instal-

pavers. Regular site clean-ups such as

lation was serving. In order to determine

litter drives will assist in maintaining

the required infiltration rate needed to

site functionality. He notes that the

handle five-minute design storms with

most efficient means of maintenance is

50-, 100- and 200-year return periods,

restorative vacuum-cleaning with the aid

the effective rainfall was calculated by

of specially designed equipment.

multiplying the design rainfall by the

Barnard concludes by saying that SA

ratio of the total catchment area to

needs an overarching governing design

the PICP area.

code to ensure permeable paving systems are designed and installed correctly, and

Full study

that contractors use specified materials.

Barnard investigated how age and envi-

Moreover, he cautions that PICP should

ronmental factors affect PICP systems

not be installed at all if property-owners

and determined that without mainte-

are not prepared to perform regular main-

nance, PICP typically loses about 25%

tenance, as sites can become hazardous

of its infiltration capacity per year. This

when fully blocked.

PRECAST | ISSUE ONE | 2020

indicator of a country’s economic growth, as it is the key input material in infrastructure development. Much like the rest of the modern world, the foundation of SA is built on this premise.

THE REAL THREAT OF USING SUB-STANDARD CEMENT

Yet according to Njombo Lekula, MD

lives at risk. Usage of sub-standard ce-

ing to increased repair or maintenance

of PPC RSA, sub-standard cement prod-

ment has various implications that may

costs, injuries and fatalities due to

ucts are threatening the built environ-

negatively affect the sustainability of

structural failures or collapse.

ment industry and placing South African

buildings and structures, thereby lead-

During a normal market surveillance exercise whereby competitors’ products were all tested for comparison, PPC found that some products supplied by cement producers were sub-standard and warranted further investigation. Digging deeper In an effort to protect the greater South African cement industry and consumers, PPC appointed Beton-Lab, a South African National Accreditation System (SANAS)-accredited independent laboratory, in September 2017 to physically purchase the bags itself in order to maintain the chain of custody and ensure no interference from any outside party. Part of the process was to take photographs of each bag (front, side, back panels and bag weights) to verify Letter of Authority numbers, cement type and strength class. The weights of the bags were checked and the EN strength testing in accordance with SANS 50197 for two, seven and 28 days was performed. The SA Bureau of Standards (SABS) prescribed uncertainty of measurement allowance of 2,5% was applied when analysing the resultant data. The

“PPC found that some products supplied by cement producers were sub-standard.”

results showed an inability to produce a consistent quality product and thwarting of standards. “As an independent laboratory, our work is tightly controlled, ensuring accurate data which is in no way influenced by outside parties,” says Alan de Kock, MD of Beton-Lab. Interesting findings The report was recently released and the findings were shared with the SABS and the National Regulator for Compulsory Specifications (NRCS), showing continued non-performance of the cements tested. According to Lekula, non-conformity of strength and weights of some products ranged from 11-73% of the sample set. “T his failure to conform to local standards not only has an impact on the

(Above): A PPC infogram.

PRECAST | ISSUE ONE | 2020

structural integrity of buildings, but also

INDUSTRY NEWS

The cement industry is seen as a good

INDUSTRY NEWS 12

poses a threat to possible damage of

durability of mortar or concrete is primar-

property and even loss of life, should the

ily dictated by the amount and strength

â&#x20AC;&#x153;The use of sub-standard cement

walls come tumbling down,â&#x20AC;? says Lekula.

performance of the cement which is used.

products has been identified as one

have of their businesses and standards.

It was also found that most of the

Retailers, builders and construction com-

of the main causes of building collapse

sub-standard cement products carry the

panies are also at risk of future legal action

globally. PPC has decided to take a stand

SABS stamp. This is a mark of regulatory

or loss of income, as selling and using these

against sub-standard cement products

approval, instilling trust in the product

sub-standard products can have a nega-

to ensure the safety of consumers and

being sold and guaranteeing that, if it

tive effect on the perception consumers

longevity of structures,â&#x20AC;? says Lekula.

is used in accordance with the instructions, it will result in a structure which is robust and safe. Local standards Local cement producers have stringent internal quality regulations in place to ensure compliance of their products. However, with some cement producers supplying the market with sub-standard extended products, Lekula questions the long-term effect on the South African built environment, as well as the sustainability and impact on our infrastructure. With non-compliance of quality and durability standards, consumers are unaware of the risks they face. It takes up to 28 days for cement to develop strength and fly ash does not start developing strength before that time. The

of SA’s legal quarrying industry will the construction of appropriate infrastructure be able to take place. This is according to the director of mining industry association ASPASA, Nico Pienaar, who says the quarrying industry in SA is technically advanced

QUARRIES ESSENTIAL TO A SUSTAINABLE CONSTRUCTION INDUSTRY

and able to supply materials for modern construction techniques. However, many of the country’s quarries are under threat due to illegal operations and ill-considered borrow pits, which are undercutting the prices of formal quarries and bringing many to their knees. Pienaar warns that without wellmanaged quarries operating in our towns and cities, the cost of construction will become unaffordable for government, developers and home-owners. If the quarries are allowed to disappear, we will see similar problems arise to those of the Eskom energy and water crisis, where too little is done too late – and the country’s citizens will bear the brunt. No tomorrow “Imagine if we needed specialised materials to build a dam wall, tunnel or hospital, or private contractors needed high-strength concrete for mine shafts, high-rise buildings or advanced new construction techniques. Imagine if we couldn’t supply them because our formal quarrying industry’s mining experts, blasting professionals, mineral processing engineers and skilled workers had left the sector, due to the quarries closing. Illegal miners and small-scale borrow pits have neither the skills nor the expensive capital equipment to produce such materials,” says Pienaar. “By supporting illegal miners or establishing ill-considered borrow pits to meet shor t-term construction requirements more cheaply, government departments, municipalities and construction firms would be complicit in the demise of our quarries, which would then inevitably lead to the demise of the formal construction industry in SA. While short-term price gains may seem attractive, they undermine the livelihoods of thousands of workers who’re gainfully employed in the formal quarrying sector with its strenuous health, safety and

PRECAST | ISSUE ONE | 2020

environmental laws, as well as compli-

growth, a strong demand for infrastruc-

ance with employment criteria,” he adds.

tural development is required and this

He explains that quarries, by their

needs to be supported by legal quarry

nature, need to be situated either in or

operations in every town and city. “We’re

near towns and cities to avoid expensive

calling on government, contractors,

transport costs that would make them

developers and the formal construction

unaffordable. All too often, residents

industry to recognise the important roles

only see the negative side of quarrying,

played by well-resourced, well-equipped,

such as the use of heavy equipment

formal quarries and to support them in

on site, blasting or increased heavy

the interests of sustainable construc-

vehicle traffic and become upset at the

tion,” says Pienaar.

thought of having a “big, dirty” quarry nearby. These people don’t realise that formally registered quarries belonging

Quarries create employment for

to the association are far from being

surrounding communities

bad neighbours.

The value of well-run quarries in our cities and towns was recently

Compliance matters

underscored by research suggest-

L egal quarries which ar e member s

ing that every job in the quarrying

of ASPASA must obtain

industry creates a further five

mining, water usage and

jobs in downstream operations.

environmental permits and

These figures therefore sug-

have to abide by the strict-

gest that quarries are major

est regulations possible in

contributors to regional job crea-

order to begin quarrying op-

tion efforts and, as an industry,

erations. Once in operation,

are a major driver of the national

they are heavily regulated

economy, accounting for substan-

(in terms of the impact on

tial revenues and the creation of

surrounding communities)

direct and indirect employment.

and must comply with strin-

Research done in the USA by

gent regulations relating to noise, dust

the Phoenix Centre for Advanced

and water pollution, among others. An

Legal & Economic Public Policy

additional benefit is the creation of direct

Studies shows that quarries are

and indirect jobs that are sustainable

not only beneficial to the develop-

over a long period.

ment of physical infrastructure,

In fact, the quarry industry has never

but are major contributors to the

been more responsible and committed to

building of strong local economies.

the communities in which they operate.

It also shows that these benefits

With government’s commitment to build-

last for at least 20 years.

ing new homes and the rising population

INDUSTRY NEWS

Only with the co-ordinated ef f or ts

INDUSTRY NEWS

Municipalities that rely on concrete piping for their water and sanitation requirements are investing in a product with the capacity to operate for well over a century, says CMA general manager Henry Cockcroft. He says the merits of concrete pipe

are recognised globally. A 2011 study by the UK Department for Environment, Food & Rural Affairs (DEFRA) found that only 0,125% of public sewers in the UK had to be replaced each year between 2000-2008. At that rate, it has been estimated that concrete pipe sewers installed in the UK today will take around 800 years before needing replacement. “Such durability can’t be ignored in a country such as SA, where municipalities have limited budgets for most operational needs,” says Cockcroft. Precast concrete piping is the strongest piping available and can be designed and tested to meet any loading condition. Unlike flexible pipes, concrete pipes have most of the required strength built into

CONCRETE PIPING PROVIDES UNMATCHED DURABILITY

them and the success of new projects

a n d d u r a b l e – i n f a c t, e v e n t h e

Whether the project is open-cut, deep

becomes much less dependent upon the

Merriam-Webster Dictionary says it

or shallow burial, tunnels or complex

skills of the installers.

is “able to exist for a long time without

alignments, concrete piping has the

“Concrete piping has a proven track

significant deterioration”. With con-

design and construction flexibility to

record of performance. They won’t rust,

crete pipe, durability deals with the

meet the challenge.

burn, tear, buckle and are immune to

life expectancy and enduring charac-

• Joint performance: The rigid struc-

most environmental elements. Unlike

teristics of its materials.

ture of concrete piping joints allows

flexible pipes – for which most of the

• Strength: Reinforced precast con-

for different designs, from soil-tight

structure must be painstakingly designed

crete piping is the strongest drainage

to water-tight. Pressure-rated joints

and installed in the field – concrete pip-

piping available – a composite struc-

are also available.

ing comes with design already virtually

ture specially designed to use the best

“The key to long-term performance

built in. It also has an unlimited range

features of both concrete and rein-

and efficiency lies in a material’s ability to

of pipe strengths from which to choose

forcement. The concrete is designed

retain its original shape and alignment,”

and these strengths are available for

for the compressive force and the

says Cockcrof t. “Precast concrete

selection and demonstration prior to

r ein f or cemen t f or the

pipe’s rigidity and mass allow

installation

tensile force.

it to gr eatl y ou tper f orm

“Precast concrete drainage products

• Dependability: Concrete

flexible pipe systems in this

are renowned for strength and durabil-

piping’s long-term perfor-

critical area. This formidable

ity. They won’t corrode prematurely,

mance is proven. Innova-

rigidity and strength help

deflect or move off grade to reduce

tion has made concrete

improve hydraulic efficiency

hydraulic performance, or collapse under

pipe mor e r eliable and

by minimising the resistance

loads designed into the pipe structure.

dependable than ever. This

to water flow that of ten

Concrete piping is easily integrated into

innovation includes im-

occurs when the shape or

ecosystems and widely used to accom-

provements to concrete

modate the natural channels of streams

mixes, pipe design and

at road crossings, and for storm sewers

manufacturing processes.

and outfalls in valleys and shorelines,”

• Structure and conduit: Concrete

emphasis on sustainability and ‘green’

says Cockcroft.

integrity of a flexible pipe is (Above): Henry Cockcroft, CMA general manager.

compromised. “Finally, with the current

pipe is a rigid pipe that provides both

products, concrete – unlike plastic

structure and conduit when it

piping – is less expensive to produce and

sociation has, for example, found that

arrives on site. Unlike flexible al-

consumes less energy than competitive

by specifying concrete pipe, end-users

ternatives, concrete piping has little

f abrications. Concrete pipe is also

such as municipalities will benefit from

dependence on the surrounding soil

recyclable and – when local resources

advantages that include:

for its structural performance.

are used – it can provide lower fuel cost

• Resilience: Concrete piping is resilient

• Design /construc tion flexibilit y:

The American Concrete Pipe As-

for delivery.”

PRECAST | ISSUE ONE | 2020

TECHNICAL 15

USAGE PHASE OF CONCRETE IS GREENER The energy requirements of a completed

the owner or user needs to understand

that draughts do not negatively affect

structure, once occupied and operational,

the sustainability features incorporated

energy usage for heating and cooling.

are still too often overlooked in assessing

in the structure.”

• Designing buildings to use solar energy

the “green” or sustainability status of

Impor tant design considerations

and tap into the benefits of thermal

to ensure sustainability in concrete

mass to save energy.

structures include:

• Designing structures to reduce the

ity in the design of concrete structures

• Ensuring that the building is orientated

requirements for maintenance or

should pay more attention to lowering

to take advantage of natural elements

to make maintenance simple and

energy usage during the full life of the new

to provide natural lighting, heating

cost-effective.

buildings they create, says Bryan Perrie,

during winter, cooling during summer

• Designing structures to promote

MD of The Concrete Institute (TCI).

and natural ventilation.

new developments. Architects who strive for sustainabil-

saving of finite resources by, for

• Ensuring correct window and door

example, designing systems to pro-

level of sustainability of a new building

type and placement to take advantage

mote rainwater harvesting, re-use

is heavily judged on its design with

of sunlight during winter, as well as

of grey water and other water-use

rating systems such as the Green Star

the flow of air from prevailing winds.

efficiencies.

system of the Green Building Council

Eave depths should be designed to

of SA and the Leadership & Energy in

shade the inside of the building during

Lifetime costs

Environmental Design (LEED) system in

summer, but allow winter sun to

“Engineers focus on structural de-

the USA, bestowing points for various

warm rooms.

sign, construction materials and the

sustainability initiatives during the design

• Using atriums, wind/stack ventilators

construction process itself, as well as

stage of a building.

or ventilation panels to assist natural

recycling, resource conservation and

ventilation, and under-floor vents or

embodied energy. These are commend-

Cost offset

permeable ceilings to unlock the

able, but far too little attention is paid by

“However, these systems often lead

thermal mass in the upper part of

this profession to the use phase and full

to chasing poin ts f or a p ar ticular

concrete slabs.

life-cycle assessment of new structures.

rating, rather than concentrating on

• Choosing roofing and external wall

real sustainability stretched over the

material and colours that will reflect

lifetime operating energy consumption

entire life-cycle of a new structure,”

heat away (lighter colours) from the

c o u l d r a n g e f r o m 8 7- 97 % o f t h e

says Perrie.

building or absorb solar energy (darker

structure’s total energy requirement,

He adds that there are substantial

colours, dark floor tiling) to reduce

while the embodied energy accounts

economic benefits to considering life-

energy demands for heating or cooling.

for only 3-13% of the total energy. This

cycle costing from the outset. “The

• Choosing the correct insulation type

makes it clear that the use phase of

potential increase in cost during the

and location. A well-insulated roof and

a building is the major contributor to

design and construction phases of a

floor may keep the interior temp-

sustainability,” says Perrie.

‘green’ structure will generally be more

erature cooler in summer and cut

than offset by the savings from reduced

air - condi tioning costs, bu t may

energy consumption during the use

pr e v en t w in ter solar hea t f r om

phase of the concrete structure. The

being absorbed into the interior of

architect or designer needs to assess

the building.

the inter-relationship of all factors, while

• Air- and weather-proofing to ensure

In many countries, including SA, the

PRECAST | ISSUE ONE | 2020

“Research has shown that a building’s

(Above, from left): Atriums could provide natural lighting in any type of new structure, particularly heavy electricity consumers such as shopping malls, and energy-saving measures during the use phase of a city’s concrete structures are often overlooked by the designing profession, says The Concrete Institute.

TECHNICAL

CONCRETE OFFERS SUPERIOR STRUCTURAL INTEGRITY

Concrete construction can produce

concrete the product of choice when

durable structur es r equiring lower

constructing in areas where high winds,

maintenance than competitive materials,

hurricanes, tornadoes or seismic condi-

s a y s G ar y T h e o d o si o u, s t r u c t ur al

tions are considerations. This lateral

engineer of The Concrete Institute (TCI).

stiffness also means that occupants

Theodosiou says that because of

of concrete towers are less able to

its exceptional longevity and ease of

“Due to its versatility, aesthetic ap-

most economical choice for engineered

peal, cost-effectiveness and availability,

structures. “Tilt-up concrete panels,

concrete is changing the face of SA’s

for example, serve not only to enclose

landscape. Increasingly, cutting-edge

the buildings, but to carry roof and wind

engineers and architects are making

loads – eliminating the need to erect

concrete their material of choice.

separate cladding and structural systems,” he explains.

(Above): Tilt-up concrete panels enclose buildings and can carry roof and wind loads to eliminate the need for separate cladding and structural systems.

perceive building motion.

construction, concrete is invariably the

“As requests for changes aren’t uncommon in any construction project, the

“Concrete is often left exposed on

design flexibility of concrete allows the con-

interior walls because of its aesthetic

tractor to accommodate design changes

appeal, durability and inherent fire-re-

after the process has begun,” he adds.

sistance. Exposed concrete reduces the

TCI can provide design advice and

need for, and cost of, applying additional

information on the benefits of concrete

fireproofing to satisfy building codes.

construction in commercial, retail and

“A major ad vantage of concr ete

industrial sectors. The TCI Information

construction for engineered structures

Centre holds and is continually accu-

is the material’s properties of density

mulating technical information relating

and mass. Lateral stiffness, or resist-

to design, use and construction of con-

ance to horizontal movement, makes

crete structures.

COMPANY NEWS 17

CONTRIBUTING TO SPORTS DEVELOPMENT AfriSam has collaborated with Swart-

excited about this project because it will

Skills development

land Local Municipality, Hope Through

positively impact the lives of community

AfriSam has an intensive community

Action and other partners towards the

members, especially the youth.

involvement programme that focuses

construction of a much-needed indoor

on making a sustainable difference to

and outdoor community sports centre

Community care

the communities in which it operates.

in Wesbank.

“One of our key focus areas is to cre-

T he company is invol ved in various

The centre consists of sport and public

ate a better future for our children.

projects nationwide, with the aim of

engagement facilities which will benefit

We’re proud to be associated with a

empowering and equipping communities

thousands of residents in Malmesbury,

programme that will equip the youth of

with knowledge and skills, as well as

We s t e r n C a p e . T h e C M A m em b e r

Malmesbury not just with physical skills,

pr o v iding them with the tools and

contributed R2 million towards the

but – equally importantly – with life and

facilities to become self-reliant.

construction of the Swartland Community

leadership skills as well,” says Sehloho.

T he company also has a long-

Sports Centre, which will house a sports

“The Swartland Municipality extends

standing relationship with the Jo Dolphin

hall, counselling and training rooms,

its sincere thanks to AfriSam for its social

Association for People With Disabilities

a resource centre, seating for public

contribution. The collaboration between

( APD) in Malmesbury. In addition to

events, a full-size, grass-surfaced football

the company and the municipality has

the donation of assistive devices and

pitch and a multi-purpose outdoor court.

made it possible for us to invest in areas

therapy equipment, the company also

which urgently need upliftment.

invested in enhancing the skills of the

Community members will also benefit from various programmes at the centre,

“We greatly appreciate AfriSam’s

carers, teachers and parents at Jo

including life skills and leadership courses,

efforts towards establishing a conducive

Dolphin APD, as well as upgrading the

as well as training in various sport

economic development climate for the

facility to meet the needs of pupils.

skills. Mathapelo Sehloho, Af riSam

area,” says Olivia Fransman of the

ESD professional, says the company is

Swartland Municipality.

“A f r i S a m’s o v e r a l l c o m m u n i t y uplif tment mission is to understand the needs of society and communities in areas where we do business in order to make meaningful and sustainable contributions to their upliftment and long-term development. We believe the Swartland Community Sports Centre will play a vital role in achieving this objective,” says Sehloho.

(Left): Johan Scholtz, works manager at AfriSam’s Rheebok aggregate operation and Mathapelo Sehloho, AfriSam ESD professional, at the opening of the sports centre. (Top left): AfriSam donated R2 million towards the construction of this world-class facility for the community of Malmesbury. (Top right): The sports centre will accommodate a wide variety of sport disciplines.

PRECAST | ISSUE ONE | 2020

COMPANY NEWS 18

NEW LABORATORY PROVIDING SOLUTIONS CMA non-pr oducer member Chr yso

new concrete aesthetic range. Accurate

Southern Africa has upgraded its Jet Park

measurement of colour can be conducted,

laboratory in order to expand its solutions

allowing customers to easily match the

to customers in fields including aggre-

colours required for a particular project.

gates, concrete aesthetics and cement.

The expansion of technology also means

S t a f f e d b y sp e cialis t engine er s

that the laboratory can scientifically

in interface physical chemistry, the

test demoulding oils, another important

laboratory conducts both research and

aspect of the company’s offering.

development (R&D) and testing. It also designs its own molecules for industrial-

Cement testing

scale production.

Mlalazi highlights that the laboratory has

“There are a number of challenges

expanded its expertise into cement test-

facing our customers, including energy

ing as well. “As part of our R&D function,

costs, environmental regulations and the

we’ve acquired additional equipment to

recently introduced carbon tax,” says

facilitate testing of cement,” she says.

Mpume Mlalazi, R&D man-

“This can now be done in a

ager at Chryso Southern

pure molecular chemistry

Africa. “By enhancing our

environment.”

world-class laboratory fa-

I n a d d i t i o n, m i c r o -

cility, Chryso can develop

concr ete evaluation is

solutions that mitigate

used to optimise admix-

these challenges.”

ture selection to cement performance. She empha-

Special services

sises that this work has

Among the capabilities

put the company “ahead

o f the labor ator y is a

of the game” in finding

recently-launched sand

energy-saving solutions

and

clay

diagnosis

and meeting the impact

tool (patent pending) f or accurate

of carbon tax legislation. The laboratory

quantification of delirious clay minerals

can assist with testing and R&D related

i n a g g r e g a t e s, s a y s M l a l a z i . T h i s

to both extended cement and concrete.

helps customers address the growing

“A l l w o r k i s c o n d u c t e d w i t h i n

issue of problematic aggregates in

stringent standards,” she says. “These

a cost-effective and environmentally

include the ISO 9001 quality system,

responsible way.

ISO 14001 for environmental protection

“Our solutions, rheology robustness

and ISO 18000 for safety. We also

enhancers and clay enablers use

test water quality to ensure we only

polymer science to allow customers

discharge clean water and recycle water

to use readily available aggregates,

wherever possible.”

without having to wash the material

T he company is committed to

ex tensi vely with water,” she says.

research, which is enhanced by collab-

“The environmental benefits of this

orations with local universities. The

technology are substantial, especially

laboratory also engages graduates from

in water-scarce areas.”

these universities, who are mentored

The facility has an extensive colourtesting capability to support Chryso’s

by Chryso specialists as part of their professional development.

“The company is committed to research, which is enhanced by collaborations with local universities.”

(Top): New laboratory equipment for wet cement chemistry testing. (Above left): Mpume Mlalazi, research and development manager at Chryso Southern Africa. (Above, from top): Spectrophotometer for colour measurement and polymer synthesis for rheology and clay enablers.

PRECAST | ISSUE ONE | 2020

AWARD FOR TOILET DESIGN CMA member Rocla was recently awarded a certificate of recognition for its lightweight concrete toilet top structure by technical assessment agency Agrément SA at a function held in Pretoria. Rocla’s precast concrete sanitation unit is a costeffective solution to one of the most basic and essential needs in SA for clean, hygienic and cost-efficient sanitation in schools and homes in rural areas. The innovatively designed sanitation units were certified as “fit for purpose” by Agrément SA after catching the eye of Deputy Minister of Public Works & Infrastructure Noxolo Kiviet, as well as other delegates. Safer schools “We described the unique features of our sanitation units to the Deputy Minister and explained how the product could solve the problem of non-existent hygienic ablution facilities at many schools and – in particular – resolve the issue of pit latrine deaths of young children in schools and their homes,” says Malebusa Sebatane, marketing and communications manager for the Infrastructure Specialist Group (ISG). She adds that the unit was designed to provide a viable, dignified, safe and sustainable toilet unit to even the remotest corners of SA. All Rocla’s sanitation units are designed to save water by functioning on the existing grey water output from a household, rather than requiring fresh drinking water. For municipalities and home-owners with pit latrines, the Rocla solutions on offer include an upgrade to the Water Research Commission-endorsed twin-leach pit technology at a reduced cost for a new installation. Agrément, which was launched in July 2018, is a fully-fledged legal entity of the Department of Public Works (DPW). Its certificates are comprehensive advisory documents that will assist building authorities and other relevant players to assess the in-situ suitability of any innovation. Local upliftment “The Deputy Minister was particularly interested in the unique ‘community cast’ methodology with which all the new Rocla toilet structures and sub-structures are manufactured. “This system was developed by Rocla specifically to benefit rural and township economies, with a strong emphasis on local job creation and skills transfer. This, of course, aligns 100% with the DPW’s Expanded Public Works Programmes,” says Sebatane. (Above, from top): Malebusa Sebatane of the ISG and Billy Qiqimana from Envirosan and a Rocla toilet and Envirosan amenities.

PRECAST | ISSUE ONE | 2020

SOLUTIONS FOR THE PRECAST INDUSTRY Home-grown chemical and building product supplier, A.Shak Construction Chemicals, has come a long way since it entered the market with its exciting range of shutter release oils nearly 60 years ago. Its products soon became well known and the company began expanding its range to include a wide range of specialist retail products for the DIY and professional building market.

A STRONG FOUNDATION FOR INFRASTRUCTURE SUCCESS

The company was initially established to provide solutions for challenges facing precasters and contractors and continuously developed new products to meet requirements of the everchanging industry. New techniques and advanced materials

ROCLA is South Africa’s leading manufacturer of pre-cast concrete products.

meant construction methods and materials were changing and

Surpassing 100 years of product excellence.

close co-operation has remained a hallmark of its service and

• • • • • • •

required innovative solutions. The company had to work closely with its clients in order to find the right solutions for each construction challenge. This support up to the present day. A.Shak is a respected supplier of quality and reliable products to the industry.

Pipes Culverts Manholes Poles Retaining walls Roadside furniture Sanitation

“We pride ourselves on our long history of service, our innovativeness and passion in responding to the needs of our customers and adding value to their operations. “We aim at becoming the foremost supplier of construction chemicals to the civil, building and mining industries and to provide specialised products, especially for the precast concrete manufacturing industry, whether it be small

Including other related products within infrastructure development and related industries. Visit us on

www.rocla.co.za

for our nationwide branches

decorative items or large structural or civil castings. “As a homegrown chemical company, we’ve always been wholly focused on providing solutions for Africa that promise uncompromised quality of both products and service,” says Cindy Engels of A.Shak Construction Chemicals. (Top): Stack casting using A.Shak release oils. (Above): Cindy Engels of A.Shak Construction Chemicals.

PRECAST | ISSUE ONE | 2020

EQUIPMENT SHELTERS

The risk of theft of railway signalling

to reduce tampering, theft and damage.

units, batteries and equipment f or

Cast in one complete structure,

cellphone towers, security surveillance

with a cast-in base and thick, high-

electronics, photo-voltaic and wind

strength walls, the shelter is virtually

farms and other high-value support

impene tr able. Damage to or entr y

and back-up equipment can be reduced

through walls or the roof is also reduced

through the installation of equipment

due to the use of a very high steel

shelters from CMA member Rocla.

content in the manufacture of the units.

The company has partnered with

Each unit has two holes on either side

entities such as Transnet and South

for handling and installation, a specialised

African Railways to provide custom-

heavy-duty door and sufficient space

designed precast concrete security

inside for equipment and movement.

units to house all the equipment which is

T hese holes also provide suf ficient

required to control the signalling units. These units are placed alongside the railway track next to the signal units.

PRODUCTS

VERSATILE PRECAST CONCRETE

ventilation, while still maintaining the mortar solutions are vulnerable. The design team at Rocla ensured

security of the unit, for equipment housed inside.

Roclaâ&#x20AC;&#x2122;s precast concrete equipment

that the unit design was practical

The equipment shelter is a cost-

shelter is a durable concrete structure

for handling and transportation, yet

ef fective and reliable solution that

that can be custom-manufactured to

strong enough to deter possible break-

can be applied across a multitude of

meet the clientâ&#x20AC;&#x2122;s requirements and is

in attempts. Replacement costs of

industries.

able to withstand the kind of attempted

sensitive equipment are exorbitant and

break-ins to which typical bricks-and-

the equipment shelter is a solid solution

(Above): Security box shelters.

The Latest Technology in Precast Prestressed Concrete Products

Tel: 011 423 2700 / Fax: 011 423 2717 info@elematicsa.co.za / www.elematic.co.za

PRODUCTS 22

With the call for precast concrete walling growing across the globe, the task of developing better and faster techniques to produce advanced, efficient machinery has fallen on equipment manufacturers. Simultaneously, quality is of the highest

SETTING UP AN EFFICIENT WALL

PRODUCTION LINE of automation to speed the process.

documentation during the whole

concern and companies like Elematic,

The company has a wide range of

manufacturing process are important

based in Finland, have responded with

o ther lay ou t op tions f or di f f er en t

to ensure consistency in production and

diverse product ranges to suit different

capacities which have been proven to

quality control. Table moulds, for example,

applications. Its SEMI, PRO and EDGE

perform well in many existing factories.

are a long-term investment. You have to

equipment ranges were developed to

“Our strength lies in our customised

ensure that the moulds can support the

assist precast manufacturers to meet

wall production solutions,” says Toni

requirements set for the wall element.

the output required with varying degrees

Koitmaa, pr oduct dir ector f or wall

Table moulds must be flat and straight

technologies.

and must withstand the load placed on them without bending. It takes a lot of

Transfer wagon

expertise to make mould tables within

“One device that seems to be making

strict tolerances,” explains Koitmaa.

a huge dif f er ence in impr ov ing the efficiency of wall production lines is the

Casting machine

central transfer wagon, especially when

He adds that the casting machine is

the product range includes both simple,

another crucial piece of equipment.

fast-moving elements and complex panels

Elematic’s unique Comcaster is very

that require more production time.

accurate and fast, while allowing for

“T he central wagon moves the

lower water-cement ratios. It can also

elements that take more time to be

cast stiffer grades of concrete than

fabricated away from the main line, so

conventional casting machines and

bottlenecks in production are avoided.

reduces surface finishing time.

T his allows the elements that ar e fabricated faster to move forward and makes production very flexible. “Pre-defined processes and proper

(Above): The Elematic PRO Wall system. (Left): Toni Koitmaa, product director of wall technologies for Elematic.

PRECAST | ISSUE ONE | 2020

speeds up the production cycle, since

mated. The PRO Wall line consists of a

only casting and hardening take place

circulation line, optional battery moulds

ef ficiency and safety are important

inside the battery mould. Using it is a

and tilting tables.

go als. One c an use hal f the usual

great way to increase capacity,” says

Theoretical capacity: 680 -1 20 0m ²/

am o u n t o f w o o d n e e d e d f o r t a b l e

Koitmaa.

day (one casting)

Personnel:

12-20

moulds, battery moulds and column and

“Digitalisation also goes a long way

pillar production by employing the right

towards reaching peak efficiency. Using

Production area:

2 800m²

shutter system.

digital systems can help you get the

Land area:

45 000m²

The FaMe system is comprised of

maximum capacity from precast lines

No of tables:

20-30

pushbutton magnets and aluminium side

by optimising the process at different

Typical table size:

3,8 x 9,0m

forms to replace wood and steel, which

stages of production, leading to faster

EDGE for very high capacity – in the

leads to substantial savings. It was

delivery time and saving on resources.”

annual range of 400 000-750 000m²

designed to improve work safety and

– with a wide product range and highly

lower the risk of finger injuries. Battery

Elematic wall production lines

automated precast production. The

moulds, which are used to cast solid

SEMI is for precast wall production of

tables move automatically between the

load-bearing walls, can likewise have a

70 000-150 000m² per year. SEMI Wall

production steps for high productivity.

big effect on efficiency.

features straightforward and easy-to-

Logistics are enhanced with a central

learn basic technology.

transfer wagon that ensures smooth

Cold shutter

Theoretical capacity: 280-600m²/day

traffic. Productivity is further improved

The cold shutter system, which is offered

(one casting)

by fully automated concrete transporta-

by very few equipment manufacturers in

Personnel:

tion and an automatic shuttering station.

the industry, practically doubles the

Production area:

2 000m²

Theoretical capacity: 1 600-3 024m²/

capacity of a standard battery mould.

Land area:

20 000m²

By transferring the cold shutter plates

No of tables:

10-15

Personnel: 30-35

to the battery mould after the previously

Typical table size:

3,5 x 8,0m

Production area:

9 000m²

Land area:

70 000m²

day (one casting)

cast elements have been taken out, the

PRO is for precast production in the

casting cycle is significantly accelerated.

annual range of 170 000-300 000m².

No of tables:

40-60

“T he cold shutter system r eally

All the PRO key functions are auto-

Typical table size:

4,0 x 10m

PRODUCTS

Decreasing waste in the precast production process and improving cost-

PRODUCTS

THE RIGHT PRODUCT FOR THE JOB In the current challenging local market environment, it is important to ensure that cost-effective, high-quality solutions are sought out and used on construction

sites – irrespective of whether they are smaller renovations or larger infrastructure projects. Each construction site presents its own requirements and challenges, and this is where local building product solutions provider MAPEI makes the difference. “MAPEI has positioned its offering not as individual products, but as a total system solution for construction projects. With our expansive range of products, we can develop and specify a complete solution for use on site,

has banked from various prestigious

T he M A PE I r ange includes v ar ious

eliminating the risk that comes with using

projects worldwide,” says Coll.

primers and bonding promoters which

different products that originate from

These include:

provide for increased adhesion and

different suppliers,” says Shane Coll,

Repair and skimming mortars: The

strength between different layers of

building products manager for MAPEI SA.

MAPEI range of repair and skimming

“Our products are used throughout

mortars includes several products that

Soundproofing. MAPEI offers sound-

the full construction phase of a project,

meet varying requirements and technical

proofing products which contribute to

from foundation to roof. It’s important

needs within the local construction

the lessening of noise levels in completed

that high quality and standards are always

market, giving customers’ concrete

applications.

maintained and never compromised.

render the strong, smooth finish needed.

Waterproofing solutions. MAPEI

Failure to do so could have serious

Cementitious and epox y grouts

has an extensive range of waterproof-

consequences and failures later within

de v elop e d f or use in anchor ing or

ing products meeting the complex and

the project life-span,” he adds.

repairing concrete structures.

technical requirements of waterproofing

the application.

Anti-corrosion coatings. This range

on site. This includes cementitious, emul-

Global products

p r o v i d e s s o l u t i o n s f o r p r o t e c t in g

sion and acrylic-based waterproofing,

The MAPEI building range has imported

concrete on the surface, as well as

protective waterproof coatings, water

products which have been developed in

protection for steel reinforcement rods

repellents and bandage systems.

the group’s world-class R&D facilities

within the concrete.

“We offer our customers/applicators

around the globe, as well as locally

Crack repair and sealants. A

not only these solutions, but also the

manufactured products which have been

comprehensive range of crack repair

technical support and training needed

developed with strict adherence to the

and joint sealant products.

in order to ensure that there’s every

group’s international standards.

ISSUE

TWO • 20

Repair and levelling screeds. MAPEI

chance of success when applying MAPEI

“We back up our solutions with

provides various substrate repair and

products. We work closely with the

expertise and knowledge not only from

preparation requirements in anticipation

applicator throughout the process and

our local technical team, but also from

of flooring.

thereafter follow up to ensure everything

the over 80 years of experience the group

Bonding promoters and primers.

THE CM

A – QU

ALITY

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NCRE

E • 20

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PRODUCTS 25 (Left): VerticArt is a cementitious mortar specifically designed for application to vertical surfaces, to create reliefs and textures which can be sculpted and carved. (Above): The earth's surface is represented by the sculpted rock layers that wrap the staircase vertically. (Below): VerticArt was used to create reliefs and textures which were sculpted and carved.

CMA non-producer member Chryso has supplied innovative products to The Trinity Session for an impressive artistic creation

ART AT THE LEONARDO

in the foyer of The Leonardo in Sandton. Its VerticArt was chosen as the material of choice when The Trinity Session, a creative production team, embarked on the curation of a sculpted representation of a cross-section through earth, showing the strata formed by tectonic plates shifting and colliding, to form the intricate patterns of geological formations. Marcus Neustetter, a director of The Trinity Session, explains that this project called for an earthy, robust medium such as VerticArt, which is a cementitious mortar designed for

for a vertically applied maximum thick-

application to verti-cal surfaces. The

ness of 150mm, making it ideal for relief

chemical make-up of the product allows

three-dimensional (3D) artwork.

team, and took seven weeks to complete. The scale, innovative material, product methodology and conceptual approach ensured that the programme was not

Work of art

just a financial prospect for the materials

It was applied in various thicknesses and

supplier and the artistic curating team,

then carved and textured using palette

but rather an opportunity for upliftment

knives, trowels, chisels, straight edges

and growth for many of the artists,

and wire brushes, to the exact creative

including emerging creative talent.

brie f. A 0-4 8-hour car v ing window

(Above, from top): The mural called for artists, who were identified based on the relevance of their previous work and interests, to fabricate the artwork and the off-shutter concrete substrate was prepared by affixing a stainless steel mesh to the vertical wall as reinforcement. A skim key coat was applied to this mesh before application of the VerticArt.

PRECAST | ISSUE ONE | 2020

ensured that the artists had sufficient

Talented artists

time to perfect the application and

T he ar tists – Damien Grivas (team

sculpting processes necessary to create

leader), Angelique Koekemoer, Ciara

the required 3D effect.

Struwig, Marlecia Marais, Patrick Rapai,

T h e mur al w as delib er a t el y n o t

Paul Setate and Zanré van der Walt –

pigmented, resulting in a very realistic

brought their own technical and creative

artistic rendition of a cross-section

touch to realising the vision of this work.

through the crust of the earth. This was

“VerticArt was developed to allow

further enhanced with focused lighting,

artists to create reliefs and textures,

giving the effect of an upward journey

which can be sculpted and carved. This

though geological aeons as visitors

massive and bold statement artwork is

ascend the staircase. The project used

a first for Chryso’s VerticArt both in SA

4,5 tonnes of VerticArt, covering 140m2

and worldwide, challenging architects,

and scaling a height of 15m (three

designers and artists to further explore

storeys). It required the specialised

the decorative potential of concrete,”

skills of eight indi vidual ar tists, in

says Neville Wearne, Chryso Southern

conjunction with the Chryso technical

Africa’s project manager.

PRODUCTS 26

REBLOC ROAD BARRIERS ENHANCE ROAD SAFETY Concrete barriers in the median or along

Crash-tested

straight line and then assess damage

the verge of a roadway or bridge are

In order to be certified accordingly, it is a

to the concrete section. Depending on

never really noticed or considered until

requirement that each barrier system be

the severity of the impact damage, the

an unexpected collision brings one to

crash-tested in order to observe critical

barrier can then be left as is, repaired in

the reality of what’s expected of these

data for each test scenario relating to

situ or replaced with a new unit.

vehicle restraint systems (VRS).

barrier movement, passenger safety and

Justin Kretzmar, group sales engineer,

CMA member, Rocla, partnered with

also to confirm that the system does

says: “Replacement of barrier elements

REBLOC, the international leader in pre-

not break up, or the vehicle could pass

is generally only required if the damage is

cast concrete road barrier technology,

through into oncoming traffic.

such that the concrete has spalled to the

based in Austria, as exclusive licence-

Casting all the components into the

extent that the reinforcement within the

holder for its portfolio of products to the

concrete section ensures that there are

barrier is visible. It’s critical that road

southern African region.

no loose parts or accessories requiring

designers consult the relevant SANS/EU

The REBLOC system includes a pat-

safe storage during construction and

code/s list of internationally recognised

ented coupling and tension bar system,

subject to theft or vandalism during the

‘containment level’ guidelines and assess

cast into the concrete, creating a contin-

life-cycle of the barrier system. After a

the risk level for that particular road.

uous barrier chain, capable of harnessing

collision with the barriers, a maintenance

and distributing the large energy forces

vehicle must realign the barriers into a

associated with a vehicle collision. European and South African codes, EU1317 and SANS 51317 respectively, provide a list of different collisions to be used by vehicle restraint system designers and road engineers. Accordingly, REBLOC has a range of products to accommodate this full list, from lowest to highest containment levels.

Growing demand “REBLOC vehicle restraint barriers have

“Each barrier system is crash-tested in order to observe critical data for each test scenario.”

been crash-tested in Europe with real vehicles in order to conform to EN code requirements and also to obtain, among other things, the ‘working width’ and acceleration severity index data specific to each barrier system and containment level tested. “Rocla has supplied the REBLOC systems on many projects across SA and Botswana, some of which have successfully sustained a considerable number of collisions. With the roads of SA constantly requiring increased safety for pedestrians and passengers alike, the REBLOC system, with its low maintenance and vandal-proof design, is perfectly positioned to make our roads safer.” Rocla barriers can also be utilised for security installations such as airports or railways, to block off road access for safety, illegal dumping or during construction projects and even for bulk material storage purposes.

PRECAST | ISSUE ONE | 2020

C oncr e te equipment manu f ac tur er PMSA has introduced a high-tech offpacking system for the world’s largest

PRODUCTS

PRODUCT OFF-PACKING SYSTEMS brick-, block- and paver-making plants. The CMA non-producer member’s

new ULTRA off-packing system provides manufacturers with a variety of options for the removal and packing of cured products from production boards into packs. It can handle production board sizes up to 1 500mm x 1 500mm and is capable of packing 650kg of concrete product per board. With cycle times of under 10 seconds, the ULT R A of f-packing system can achieve up to 3 200 production boards per nine-hour shift. Its servo-driven

marketplaces. This is in line with our

electric operation provides high-force

efforts to bring the best equipment to

and maximum travel speeds for ultra-

market to ensure our customers can

high-performance off-packing of cured

‘buy once, buy right’,” says Booysen.

products including bricks, pavers, maxi

“All our equipment is locally engi-

bricks, hollow blocks, special products,

neered and designed to withstand the

heavy kerbstones and products with up

most demanding conditions. The ULTRA

to 500mm end heights.

is built to last and operate for decades with minimal hassle and reduced down-

Servo-driven

time. Longevity results in continually

PMSA’s marketing and sales manager,

reduced cost-to-capital, as this equip-

Quintin Booysen, explains that the

ment doesn’t need to be replaced for

rotating, four-sided servo-driven packer

many years.”

head has powerful clamping for heavy products and is primarily designed for

(Above and left): PMSA’s ULTRA off-packer.

use with a stacker and de-stacker. “ULTRA is our top-of-the-range offpacking system and can be used with

Features of the ULTRA off-packer

ULTRA-3000, RE1400, RE1400-LITE,

• Robustly constructed portal

VB4X and VB4 plants. “The design of the ULTRA off-packing system enables high efficiency and pro-

frame ensures minimal de-

flection and longevity of the

structure.

duction capacities, as well as effortless

• Powerful four-sided, servo-

and precise packing of products ready for

driven clamping enables easy

strapping. It’s ideal for fully automated

li f ting o f h e a v y p r o du c t s,

packaging systems where its precision

such as kerbstones and special

movements reduce breakages and waste.

products.

“We designed it to surpass all packing

• Servo and belt-driven cross-

systems in terms of speed, accuracy and

tr a v el o f the p acker he ad

longevity through meticulous engineering

ensures the highest precision

design and the use of the world’s latest

and rapid movement of light

technologies. As a result, it includes

or heavy loads.

servo-driven controls and operation for

• The 180º rotating packer head

the highest productivity and heaviest

products and the most precise packing.

nated during packing for even

product packs.

enables layers to be alter-

World-beater

• Powerful servo-driven system

“As a South African company, we’re

enables packing of up to 650kg

proud to introduce this world-beating

of products per layer.

solution to the local and international

PRECAST | ISSUE ONE | 2020

PRODUCTS 28

GREENER AGGREGATES FOR CONCRETE Sustainable construction needs to start

mentally conscious companies who’re

at the very foundations of all business

active ASPASA members,” says Pienaar.

projects, with the sand and aggregates that constitute the largest part of just

Keep it green

about every construction project.

Building pr o f e ssionals sh ould also

This is an often-overlooked element

remember that unscrupulously operated

o f sus t ain ab l e c o ns tr u c ti o n . I t is

pits and quarries scar the environments

required that all materials used for

and contaminate water courses. Damage

ground stabilisation and concrete be

in these cases is most often left for

manufactured with sand and stone which

ready-mix or precast concrete suppliers,

future generations to clean up. That

is procured through registered legal

should be able to prove that the supply-

is why mines and quarries belonging to

entities that adhere to all the relevant

ing mine is operating with a valid mining

ASPASA have thrown their full weight

legislation relating to the environment.

licence from the Department of Mineral

behind programmes to help protect

Nico Pienaar, director of the surface

Resources & Energy (DMRE), has land-

the environment upfront and adopt

mining industry association ASPASA,

use rights from the local, provincial and

sustainable mining practices in their

sa y s tha t all t o o o f t en, sand and

national authorities, and is complying

everyday operations.

stone are overlooked by green building

with all relevant environmental protec-

practitioners, yet they constitute the

tion requirements.

“Increasing environmental awareness has prompted our members to lead by

largest component of any construction

“It’s an unfortunate fact that illegal

example and adopt a comprehensive

work. By volume, sand and stone make up

mining practices continue to scar our

compliance programme which ensures

by far the biggest percentage of the dry

landscapes and diminish the lives of sur-

compliance with regional and national

mix of concrete and it is vitally important

rounding communities and others who’re

by-laws and legislation, and requires all

that a paper trail be followed to ensure

affected by the practice. That’s why we

members' sites to be audited on an annual

the materials are obtained from legal

urgently call upon all involved in sustain-

basis to confirm compliance. The DMRE

mining operations.

able and green building projects to make

may also use the information for future

use of materials from legal and environ-

mining licence decisions,” adds Pienaar.

Sand and stone suppliers, as well as

Find our branches at www.technicrete.co.za

p a v in g | mini ng | m as onr y

SUITABLE FOR: • Car parks • Industrial Estates • Retail Centres • Pedestrian areas • Domestic Drives • Motorways | Garages • Service areas

| k erb s | erosi on

protec

APPLICATIONS: • Tongue & groove • Standard grey or traffic calming colours • Precast • Various sizes available • Highest quality

(Above): Environmentally responsible aggregates.

tio n | r et a i

ni n g

w a ll

s|d rain age

Technicrete is a subsidiary of ISG, a leading supplier of innovative infrastructure products to the construction and mining markets in Southern Africa.

PRODUCTS 29

ADVANTAGES OF CONCRETE PARKING AREAS Concrete offers several major advan-

areas – particularly those with brushed

reduce run-off, which is now increasingly

tages when it comes to the construc-

finishes – are more skid-resistant and

enforced through legislation overseas.

tion of parking areas, including lower

allow for easy installation of “rumble

And, to add to the sustainability point of

maintenance costs, reduced lighting

strips”. Concrete pavements do not

view, the concrete mix used for parking

requirements and longer life than tra-

rut or develop potholes when carrying

lots can include recycled materials such

ditional construction methods.

heavy loads.

as slag, fly ash and recycled concrete.”

Studies in the USA have shown

According to Bryan Perrie of The

that over a t y pical 20-year lif e of

Concrete Institute, a global authority

Better aesthetics

a p ar k ing ar ea, concr e te r equir ed

on concrete industrial surfaces on the

The practical considerations of laying

very little maintenance expense, while

ground, maintenance costs of concrete

the parking area also favour concrete:

maintenance for an asphalt lot ended

parking areas are minimal, with only

concrete pavements are built in

up costing as much as 80% of the initial

some joint sealing and cleaning usually

one layer, usually on a sub-grade of

construction outlay. On a Florida, USA,

required annually.

compacted earth. Asphalt pavements,

project, an asphalt parking lot ultimately cost twice as much after 20 years than a similar concrete facility. Lighting of the parking areas can also be reduced through the use of light-coloured concrete surfaces. It has been estimated that three out of 10 light fixtures can be eliminated without losing the level of lighting in a parking

“Maintenance for an asphalt lot ended up costing as much as 80% of the initial construction outlay.”

on the other hand, require an additional gravel or crushed stone base. T hen there is the question of appearance. The selection of concrete to p a v e a p ar k ing ar ea o f f er s the designer unlimited choices of texture, pattern and colour for aesthetic appeal, and the parking areas can be blended with adjacent greenbelts or equipped

lot when using light concrete surfaces.

“Asphalt parking surfaces, on the

With crime a constant problem in our

other hand, need to be treated every

“Large parking areas can be made

country, lighter concrete parking lots

few years and totally resurfaced at least

mor e in ter esting thr ough the use

create safer storage of cars, while

every 10 years. Such maintenance work

of colour, which can also be used to

reducing energy costs.

can be very disruptive to the operations

identify specific parking areas for buses,

of a commercial shopping complex or

trucks and visitors’ vehicles, as well as

office block,” he says.

directional signs for pedestrians. Parking

Concrete advantages

with water features.

Lighter-coloured concrete also lowers

“ T h e e n v i r o nm e n t a l a sp e c t s o f

areas are more than just surfaces for

temperatures in parking areas during

concrete parking lots also shouldn’t be

cars: they serve as attractive welcome

hot South African summers and, by

overlooked. The run-off’s low in toxicity

mats for offices, sports stadia, airports,

eliminating the “heat island effect”, can

and cooler than from asphalt surfaces.

shopping centres, etc and demonstrate

even lower cooling costs for adjacent

M o r e o v e r, p e r m e a b l e i n t e r l o c k i n g

quality to visitors – even before they walk

buildings. In addition, concrete parking

c oncr e t e p a v emen t s sub s t an tiall y

through the front door,” says Perrie.

PRECAST | ISSUE ONE | 2020

GLOBAL VIEW 30

SA ARCHITECTURE SHAPES UP WITH DECORATIVE TILT-UP CONCRETE Function, rather than form, has always been the predominant selection factor in precast concrete applications. But no longer, as increasing numbers of local architects are requesting decorative elements in their precast designs. According to David Kitching, general

casting required on a site that was

manager of SA’s leading tilt-up practi-

ecologically sensitive,” says De Jongh.

tioner, Bedrock Group, architects are

What follows are potted profiles of

calling for varied finishes such as tex-

some of Bedrock’s decorative tilt-up

tured and woven concrete, the emboss-

projects:

ing of company names and logos, and eye-catching lines and shapes in their tilt-up designs, as well as relief or depth. “Our aim is to enable local architects

Rubro Construction, Durban

and property developers to achieve what

Attractively embossed with the company

their contemporaries are doing overseas.

name and logo using high-density foam

Increasingly, we find ourselves moving

rubber moulds, these panels were used

away from our typical fast-track tilt-up

for constructing a retaining wall that

projects to much more aesthetic-driven

was 2,5m high. They were erected in

projects and to this end, we’ve been

the same way as tilt-up columns, which

involved in several decorative concrete

involved placing them on blindings and

projects in Durban, Johannesburg and

then casting a reinforced foundational

Cape Town,” says Kitching.

base around them.

Distribution centre Ian Bell, a director of Paton Taylor Architects in Durban, says his company uses decorative concrete in tilt-up applications on a regular basis. “We used it on the Mr Price distribution centre in Hammarsdale, KwaZulu-Natal, with bespoke patterns which came out nicely.

King Shaka Airport – Durban,

However, we mainly use it on a repetitive

Henry Fagan Architects

basis, embossing the same motif on

Resembling elephant tusks, 10 arched

Crusader Logistics, Johannesburg,

several panels.

concrete obelisks – each weighing 28

Empowered Spaces, Sonia Rodrigues

“The CAD-generated designs are

tonnes – were cast and placed on either

Low-cost entry-level features, such

handed to Bedrock for transferring

side of the entrance road to the airport

as a protruding stairwell constructed

into precast concrete using either

in 2010 and 2014. Designed by Henry

with precast concrete panels, lift the

high-density foam rubber cut on CNC

Fagan of Fagan Architects, the casting

appearance of this large warehouse

machines or steel moulds,” says Bell.

was done using concrete moulds which

from the ordinary into something special,

Anton de Jongh of Arc Architects says

were considerably cheaper than their

thereby creating a pleasant workspace.

decorative tilt-up concrete is relatively

steel equivalent and involved a process

Other precast panelling combines well

new to SA and besides its aesthetic

similar to shaping a surfboard by hand.

with the tinted windows framed in glazed

attributes, one of its major benefits

The architect wanted all the obelisks

is faster construction. “We saved two

to be the same colour in a light-coloured

months of a 14-month construction

concrete.

period on our concrete laboratory project

To achieve this materials comprising

at the University of Pretoria and Bedrock

sand, stone and white cement were set

achieved Class 1 off-shutter finishes. We

aside so that when the casting was done,

were impressed with the smoothness

each column was made from the same

and flatness achieved.

material batch. The sand and stone came

“Moreover, we were able to specify

from a single day’s quarry output and

indents on some of the panels, which gave

was washed before delivery. It was then

us additional design freedom. Another

stored in a covered area until the project

plus was the very small footprint the

was completed.

aluminium and the IRB sheeting above.

(Above): Sasol HQ, Johannesburg.

PRECAST | ISSUE ONE | 2020

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PRECAST Agrinet, Cape Town, Tim Hughes Architects Cladding wall panels in various shapes and sizes add an interesting visual

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dimension to this building. The application of cementitious mix stains the concrete to a uniform colour by being absorbed into the pores of the concrete. Unlike paint or cement, the stain will not require any

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Sasol HQ, Johannesburg,

maintenance.

architectural masterpiece. Bedrock

Sasol’s new headquarter building is an

y c nc a s t in c o

supplied 3m polished exposed-aggregate column sections which were used to

erect two tapered concrete columns that rise from the second to the ninth

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floor. The columns were designed to resemble tuning forks and are named as

such. Part of Bedrock’s brief was to cast

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in steel connecting plates at the end of each beam. The plates have a tolerance

First name:.......................................................................................................

factor of only 1mm and are connected to the beams with steel brackets.

Surname: ......................................................................................................... Address: .......................................................................................................... .............................................................................................................................. .............................................................................................................................. University of Pretoria Concrete Laboratory, Arc Architects Bedrock was challenged by the University of Pretoria to achieve an exceptionally high class of concrete finishes in the construction of a world-class concrete

Mr Price, Hammarsdale,

testing laborator y and educational

Paton Taylor Architects, Ian Bell

facility using tilt-up walls. Arc Architects

This image shows how patterns and logos

wanted the lab to show of f what is

are embossed onto concrete panels.

achievable with concrete and Bedrock

High-density foam rubber is cut with CNC

delivered superb finishes. Moreover, the

machines based on CAD designs. The

walls are decorative in that they are

rubber is then attached to the casting

shaped with depth and relief and also

surface and painted with a bond breaker

support the roof and other parts of the

before the concrete is poured.

building.

PRECAST | ISSUE ONE | 2020

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PROJECTS

(Right): Electric lamps mounted in some of the semi-arched steel frames light up the refurbished section of Longmarket St at night. (Below): Red Granary Cobbles and an artistic steel framework combine well at the made-over courtyard of the Old Granary.

A section of Longmarket St, one of the oldest thoroughfares in Cape Town’s

CBD, has been transformed from a commonplace walk way into an eyecatching urban space. The revamped section covers an area of 630m² and is situated between Harrington and Buitenkant Sts, adjacent to the historic and recently refurbished Old Granary building and a mer e stone’s thr ow from one of the city’s major tourist attractions, the Castle of Good Hope. The new layout, which involved the use of wet-cast concrete pavers and the installation of an artistic semiarched steel framework for lighting the thoroughfare, was designed by Gapp Architects. The paving is comprised of 215mm x 50mm cobble-styled blocks (Granary Cobbles) and large flagstone pavers, both custom-made by CMA member, Wellington-based SmartStone.

CUSTOM-MADE PAVERS REVITALISE PEDESTRIAN WALKWAY IN CAPE TOWN

The project highlights Longmarket

T hese include d the nar r ow ness o f

St’s symbolic significance. It is the only

Longmarket St, a blank façade on one

street that runs the full width of the

side with no natural spill-out onto the

City Bowl from Bo-Kaap to District Six

street, a low wall with spikes and lim-

and it parades some of Cape Town’s

ited lighting at night.

oldest buildings. Its importance as a

“On the plus side, the area had an

thoroughfare looks set to intensif y

avenue of well-established trees and

as people move back to District Six,

was part of an emerging neighbourhood,”

resulting in the need for a strong link

says Gapp. “Our design objective was to

with the CBD.

convert the street into an interpretation of an urban garden using existing props

(Above): The revamped Longmarket St showing the Granary Cobbles combined with large flagstone pavers, both made by SmartStone in Wellington.

Challenging surrounds

such as the tr e e s, t oge ther w i th

Gapp A r chitects says the upgrade

elements such as cobbled pavers and

Paving stones

presented several design challenges.

the semi-arched steel framework that

“The largest flagstones measure 2 100 x

we’d used in the Old Granary courtyard

600mm and the smallest 850 x 300mm.

refurbishment project two years before.

The intention was for similar-style paving

“We used Granary Cobbles (in red)

to be used all the way up Longmarket

in the refurbishment of the Old Granary

St,” says Gapp.

courtyard project and it was from that

The paving was laid by Mark Darius

installation that the name ‘Granary

Civils and the semi-arched steel frame-

Cobbles’ was coined by SmartStone. We

work was installed by 53 Power Projects.

used them in charcoal for the Longmarket

The flagstones were reinforced with

St project, where they were of fset

Y10 rebar, which means they can handle

by large flagstone pavers. These were

vehicular, as well as pedestrian traffic,

produced in numerous sizes to roughly

should the need arise. And although the

the same 4,3:1 ratio which was used

design brief called for a strength rating

for the cobbles. This made them easily

of 25Mpa, SmartStone decided not to

interchangeable during the laying process.

deviate from its standard 40Mpa.

“Our design objective was to convert the street into an interpretation of an urban garden.” PRECAST | ISSUE ONE | 2020

PROJECTS

JOHANNESBURG TWIN-DECK

HIGHWAY BRIDGE REPAIR Several Sika products were specified

SikaTop Armatec-110 EpoCem was

for structural repairs, strengthening

used as a protective coating for exposed

and the coating of a 1,02km section of

rebar and Sika Monotop-615 HB and

Johannesburg’s M1 twin-deck highway

SikaGrout-212 were applied for the repair

bridge between Newtown and Fordsburg.

of lateral and vertical bridge elements.

The bridge consists of two reinforced

SikaWrap-300 C was used for strength-

concrete deck super-structures mounted

ening reinforced concrete structures and

on concrete columns, one directly above

for increased sheer load capacity.

the other. The R15 million rehabilitation

T he br idge’s c oncr e t e sur f ac es

project required the expertise of many

were treated with the Sikaguard-705 L

specialists, including main contractor

Silane water repellent and SikaTop Seal-

Khato Civils, which was assisted by 17

107. The latter is a polymer modified

small, medium and micro-enterprises.

waterproof cement coating which is

A major challenge for all involved was

chloride- and carbonation-resistant.

the requirement for the motorway to

The council had stated that the main

remain open to traffic. Therefore, it was

concern was the safety of motorists and

anticipated that it would be difficult to

ensuring that all product applications

complete the task within the allotted

were executed correctly at every stage,

22-month time-frame. However, thanks

so all those involved in the project

to the use of Sika’s tailor-made products

were provided with training and on-site

and the appointment of a committed

support by the Sika team. This included

contractor, the project was completed

training such as surface preparation,

three months ahead of time.

product mixing and product application.

We are there when you celebrate

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PROJECTS 34

Concrete block producers tend to fall into two broad groups: those who base their marketing on price and compromise on quality, and those who are first and foremost qualityfocused. One company which falls emphatically into the latter grouping is Cape-based BluBlok. BluBlok sells concrete blocks and bricks of consistently superior quality to builders’ supply merchants and property developers. Situated on large premises in Somerset West, it operates with fully automated plants in the Western Cape. The kerb plant turns out kerbing of exceptional quality using wet casting manufacturing and indoor curing chambers. This division is spearheaded by Kevin Coetzee, who is well known in the industry. “We follow a simple, but effective business philosophy,” says BluBlok general manager Frans Benadé. “It’s based on what we term our ‘golden triangle’ of quality, price and delivery. We use it in tandem with a secondary triangle of morale, cost control and safety. Morale plays an important role. We strive to ensure that people enjoy working here and get job satisfaction. We also aim to keep costs to a minimum by getting things right the first time.

QUALITY, PRICE AND DELIVERY: BLUBLOK’S GOLDEN TRIANGLE “Our kerb moulds are made in-house,

the standard range of masonry products, such as all sizes of bricks and blocks, as well as retaining wall blocks and decking blocks. As of 2019, we’ve been making a 140mm U block which builders are using as an alternative to lintels,” says Benadé. “Quality and fair pricing count for nothing if you can’t deliver and our customers know that when they place an order with us, the products will be delivered promptly. “Housing projects in which our bricks and blocks have been used include Satari, Croyden Olive Estate and Somerset Lakes in Somerset West, as well as projects in Bredasdorp and Hawston.”

while our in-house workshop also ensures that our two plants are kept up to spec.

Quality-driven

And because our kerb plant is automated,

“Quality underpins the whole organisation

it ensures the minimal handling of our

and is based on our own quality systems.

moulds, which extends their lifespan.

Besides using the best possible raw ma-

“All our kerbs have excellent strength

terials, it involves continuous checking and

properties, uniform finishes and excep-

testing by our in-house quality control-

tionally smooth faces. They come in the

ler. In addition, our scales are calibrated

standard length of 1m and are available

regularly to ensure we get our material

in the following types: edging for pave-

mixes consistently right and besides daily

ments; barrier kerbs and channels for

in-house testing, our blocks and kerbs

stormwater drainage; a combination and

are also tested externally by professional

mountable kerb for the townships; and a

quality auditors,” says Benadé.

channel on-side kerb.” Recent projects Recent kerbing projects supplied by BluBlok include roads in Moorreesberg, Ceres, Lutzville and Montague Gardens. In addition, the company has supplied Burger & Wallace Construction, Cornfield Construction, Shar Civils, Martin & East and Asla Contruction with kerbs for various road projects. “Our block range is made to SANS 1215:2008 standards and comprises

(Top): BluBlok’s storage yard and precast concrete factory. (Above, from top): BluBlok’s fully automated kerb plant and specially embossed BluBlok kerbs prior to delivery. (Left): BluBlok kerb production and marketing manager, Kevin Coetzee.

PRECAST | ISSUE ONE | 2020

PROJECTS 35

CAST-STONE COBBLES COMPLEMENT NEW CENTURY CITY PARKADE Clad with an attractive per forated aluminium screen, P3 was built for the Rabie Property Group by main contractor WBHO. It was designed by Vivid Architects (project architect – Nic Cloete) and

A pedestrian precinct and garden courtyard which flank P3, a recently completed three-storey parkade adjacent to a Virgin Active gym at Century City, has been paved with Jura Cobbles manufactured by Cape-based caststone producer and CMA member Revelstone.

the project’s civil work was done by Neil Zaaiman Civils.

“We chose Jura Cobble because it’s

Landscape architect Alistair Turrell of

a refined product with a very regular

Planning Partners designed the landscape

module,” says Turrell, “and its colour

installation for the pedestrian precinct in

tones complement the dark brickwork

collaboration with Vivid Architects and

of the garden walls and the perforated

the Jura Cobbles were laid by TJ Paving

aluminium screens.

on a sub-base of 150mm G5 aggregate.

“This is a high-traffic pedestrian zone

Combining paving space with beds of

and the irregular composition of the

indigenous foliage and trees, the paved

planting zones in the courtyard lent itself

precinct includes benches clipped onto the

to the herringbone pattern which was

raised beds, making it a space for relaxa-

adopted for the layout of the cobbles.

tion, rather than a mere thoroughfare.

They exhibit no differentiation in direction,

nor extensive patterning which might have competed with the architecture. “Moreover, we know that Jura Cobble is a durable product which has stood the test of time. We first used it 10 years ago at the Business Centre in Century City, where it still looks as good as new.” Revelstone’s Jura Cobble has also been used on several other upmarket projects, including the V&A Waterfront’s No 5 Silo project, where it lines an indoor walkway on the ground floor.

PRECAST | ISSUE ONE | 2020

PROJECTS 36

Precast concrete accounts for the major portion of the building materials used in the construction of a shopping mall directly above a 390m section of the KwaZulu-Natal South Coast railway line at Isipingo Station. Built for Prasa and spanning 20 520m² over two floors (excluding the ramps and existing building), the new building is being erected on either side of and integrated with the existing Isipingo station building, which – in turn – is being modernised and upgraded. The new building comprises two floors, the first to be used for retail space and the level above for parking. The precast portion of the mall structure, designed by specialist precast concrete contractor Bedrock Group, is being built using precast columns, beams

PRECAST FACILITATES SHOP

and hollow-core slabs, as well as precast

of various sizes, cast over pile caps,

parapet walling for the upper floor.

propped with braces and adjusted into a vertical position with shims. After

Unimpeded traffic

additional reinforcing was installed,

A major proviso for the construction of

concrete was poured around the base of

the mall was that the line remain open to

the columns. The braces were removed

normal rail traffic during construction. In-

after 14 days once the concrete had

situ construction, which involves shutter-

cured sufficiently.

ing and propping, would obviously not have worked and therefore precast concrete

Heavy beams

proved the only viable building option.

Of the 211 beams used on this project,

All 141 columns were produced on

132 measured 3-9m and were cast at

site and were cast with corbels for beam

Bedrock’s production yard in Westmead.

support. However, a variation order was

Up to 15m long, the remaining 79 beams

issued after the first 121 units had been

were cast on site.

cast, changing the building from a three-

T he beams were placed between

to a two-storey structure. This meant

(Above): A beam supports hollow-core slabs prior to the casting of the structural topping.

the columns to support the 10m pre-

the existing columns had to be shortened

(Below): A partially completed section of the mall.

stressed hollow-core slabs, which were

from 22m to 17m. Depending on the width of the flooring, the columns were placed in rows of either two, three or four abreast. Cast with starter bars flanking a column foot of 340mm x 600mm x 1 400mm, they were lowered onto structural blindings

(Top): A beam is about to be lifted by the 460-tonne mobile crane prior to placement between the western abutment and the central pier. (Above): Concrete pouring of the pavement. (Left): The central diaphragm’s reinforcing prior to the pouring of concrete. The Y40s can be seen protruding from the ends of the beams in a knitting formation. (Right): The completed bridge.

(Above): The bottom end of some columns showing the base foot flanked by starter bars.

PRECAST | ISSUE ONE | 2020

PROJECTS 37

PPING MALL OVER BUSY RAILWAY LINE supplied by Echo Prestress. The beams

require propping or shuttering, which

at ground level in order not to overload

were lowered onto the column corbels by

wouldn’t have been possible while the line

the pipeline and allow access for cranes

mobile crane and were “stitched” across

was operational.”

and trucks from the casting beds to the

the columns. The reinforcing involved

The precast parapet walling was

building site. Some casting beds were

straddling the beams and the columns

cast on site by Bedrock in sections up

close enough to the building for the

with Y32 bars.

to 15,6m long and 1 510mm high. It was

precast elements to be lifted directly

The beams were “stitched” together

attached to column corbels with steel

from the beds into position. However,

around the internal columns before the

brackets and braced with in-situ stub

most units had to be double-handled

60mm structural topping was poured.

columns cast onto the slab.

using cranes and trucks, either over the

The 15m beams in the two-span configu-

pipeline, across the “bridges” or from

ration were partially stressed, in addition

the public road.

to some supplemental non-pre-stressed

Casting beds were used multiple

reinforcing. This offered a better solution

times for various precast units and

and simplified the reinforcement and

the sequence of casting was carefully

redistribution of stresses, as well as

planned so that precast elements could

improving deflection and crack control.

be stacked in the order required.

It was important to keep deflection to a minimum, as some of the beams were

Project team

close to the railway’s overhead high-

The project’s professional team is as fol-

voltage cabling.

lows: principal agent and civil/structural engineering: Delca Systems; quantity

Monolithic structure

surveyor: Ukuza Consulting; main con-

Using the same concrete mix for the

tractor: GVK Siya Zama Building Con-

structural topping and the “stitching”

tractors; specialist precast contractor:

created a seamless monolithic structure

Bedrock Group; structural engineers

between the columns, beams and flooring.

to Bedrock responsible for the precast

Due to the railway line being used dur-

structure: Escongweni BPH Engineers;

ing the day, much of the initial placement

Surrounding infrastructure

pre-stressed hollow-core slab supplier:

of precast elements had to be done at

A public road abutting the west elevation,

Echo Prestress.

night during line shut-downs. But once

the existing station building, the railway

the first-floor slab had been installed, lift-

lines and a fuel pipeline running parallel

ing could continue during the day because

to the eastern side of the lines meant

the lines were protected.

that space for on-site casting was lim-

“Moreover, hollow-core slab flooring

ited and the casting beds were placed

was the only option for this project,”

further from the building site than would

says David Kitching, general manager of

normally have been the case.

the Bedrock Group, “because it doesn’t

PRECAST | ISSUE ONE | 2020

Three “bridges” were constructed

(Top, from left): An on-site casting bed; A column foundation trench prior to casting of the concrete blinding over the piles and members of the Bedrock team pose on one of the on-site casting beds: Lungile Phukani, David Kitching, Cathy Paver, Ganee Shaik and Africa Simamane. (Left, from top): A partially completed section of the first floor prior to the “stitching” process and workers prepare the rebar and shuttering for beam and column “stitching”.

MEMBER LIST 38

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EAGLE ROOF TILES (PTY) LTD TEL: (044) 874 0290 PROVINCE/COUNTRY: WC PILLAR: PB HORIZON BRICK & CONCRETE TEL: (012) 943 3701 PROVINCE/COUNTRY: N/W PILLAR: PB INCA CONCRETE PRODUCTS (PTY) LTD TEL: 072 646 4916 PROVINCE/COUNTRY: WC PILLAR: PB/PI LATEGAN CEMENT WORKS (PTY) LTD TEL: (021) 873 1154 PROVINCE/COUNTRY: WC PILLAR: PB/PI MANHOLES 4 AFRICA (PTY) LTD TEL: (011) 903 7023 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI MOBICAST (PTY) LTD TEL: 086 111 2346 PROVINCE/COUNTRY: WC PILLAR: PB/PI MONIER COVERLAND (PTY) LTD TEL: (011) 222 7300/7334 PROVINCE/COUNTRY: GAUT PILLAR: PB MVA BRICKS CC TEL: (012) 386 0050 PROVINCE/COUNTRY: GAUT PILLAR: PI PAVECON MANUFACTURING (PT Y) LTD TEL: 087 940 3631 PROVINCE/COUNTRY: LIMPOPO PILLAR: PI PORTLAND HOLLOWCORE SLABS (PTY) LTD TEL: (021) 972 1111 PROVINCE/COUNTRY: WC PILLAR: PI REMACON PRODUCTS CC TEL: (011) 393 5504 PROVINCE/COUNTRY: GAUT PILLAR: PI REVELSTONE (CAPE) (PTY) LTD TEL: (0861) 173 835/(021) 761 9737 PROVINCE/COUNTRY WC PILLAR: PI ROCLA (PTY) LTD TEL: (011) 670 7600 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI SHUKUMA BRICKS (PTY) LTD TEL: (041) 372 1013 PROVINCE/COUNTRY: EC PILLAR: PB

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SOLID PAVE BRICKS (PTY) LTD (CONTICRETE) TEL: (041) 365 7676 PROVINCE/COUNTRY: EC PILLAR: PB

TERRAFORCE (PT Y) LTD TEL: (021) 465 1907 PROVINCE/COUNTRY: WC

TECHNICRETE (PTY) LTD TEL: (011) 672 1425/670 7600 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI

AF CONSULTING ENGINEERS & ASSOCIATES (PT Y) LTD PROVINCE/COUNTRY: JHB

VANSTONE PRECAST (PTY) LTD TEL: (012) 541 2056/1808 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI VIBRO BRICKS & PAVING (PTY) LTD TEL: (012) 374 5533 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI WEST END CEMENT BRICKS (PTY) LTD TEL: (011) 851 1005 PROVINCE/COUNTRY: GAUT PILLAR: PB/PI NON-PRODUCER MEMBERS ABEL EQUIPMENT CC TEL: (044) 874 1876 PROVINCE/COUNTRY: EC BIRKENMAYER H (PT Y) LTD TEL: (011) 970 3880 PROVINCE/COUNTRY: GAUT CHRYSO SOUTHERN AFRICA (PTY) LTD TEL: (011) 395 9700/ (031) 564 0325/(021) 928 1660 PROVINCE/COUNTRY: GAUT/ KZN/ WC DICK KING LAB SUPPLIES (PT Y) LTD TEL: (011) 499 9400/(031) 700 2551 PROVINCE/COUNTRY: GAUT/DBN FIBERTEX SOUTH AFRICA (PT Y) LTD TEL: (031) 736 7100 PROVINCE/COUNTRY: KZN HAWKEYEPEDERSHAAB TEL: 00 459645 4193 PROVINCE/COUNTRY: DENMARK KERNEOS SOUTH AFRICA (PT Y) LTD TEL: (011) 444 3090 PROVINCE/COUNTRY: GAUT KOBRA MOULDS B.V. TEL: 003111 356 2460 PROVINCE/COUNTRY: NETHERLANDS MANITOU SA (PT Y) LTD TEL: (011) 975 7770 PROVINCE/COUNTRY: JHB PAN MIXERS SA (PT Y) LTD TEL: (011) 578 8700/8600 PROVINCE/COUNTRY: JHB QUANGONG MACHINES CO LTD TEL: +865 958 679 9557 PROVINCE/COUNTRY: CHINA REVARO CONCRETE EQUIPMENT TEL: (011) 794 827 PROVINCE/COUNTRY: JHB SIKA SOUTH AFRICA (PT Y) LTD TEL: (031) 792 6500 PROVINCE/COUNTRY: KZN

ASSOCIATE MEMBERS

ASPASA TEL: (011) 791 3327 PROVINCE/COUNTRY: JHB BRITISH PRECAST CONCRETE FEDERATION TEL: +(44) 116 232 5170 PROVINCE/COUNTRY: UK CONCRETE SOCIET Y OF SOUTHERN AFRICA TEL: (012) 348 5305 PROVINCE/COUNTRY: PTA CPI CONCRETE PLANT INTERNATIONAL TEL: (02236) 962390 PROVINCE/COUNTRY: GERMANY JC PAVING CONSULTING TEL: (011) 431 0727 PROVINCE/COUNTRY: JHB SEKHUKHUNE & ASSOCIATES TEL: (012) 346 1945 PROVINCE/COUNTRY: PTA TACO VOOGT CONSULTING ENGINEER TEL: (012) 669 0125 PROVINCE/COUNTRY: PTA YOUNG & SATHARIA CONSULTING CIVIL ENGINEERS TEL: (031) 207 7252 PROVINCE/COUNTRY: KZN CONTRACTOR MEMBERS DECORTON RETAINING SYSTEMS (PT Y) LTD TEL: (021) 875 5155 PROVINCE/COUNTRY: WC FRICTION RETAINING STRUCTURES (PT Y) LTD TEL: (011) 608 4321 PROVINCE/COUNTRY: GAUT POWERGATE CONSTRUCTION CC TEL: 071 603 5070 PROVINCE/COUNTRY: GAUT VALCAL INTERNATIONAL EXPORT CC TEL: (011) 867 2471 PROVINCE/COUNTRY: GAUT CEMENT MEMBERS AFRISAM SOUTH AFRICA (PT Y) LTD TEL: (011) 670 5500/5752 PROVINCE/COUNTRY: GAUT

PI – Precast Infrastructure PB – Precast Building

PLEASE NOTE: The above member list was correct at the time of going to print. If your details have changed, please contact Rita at the CMA offices on tel: (011) 805 6742.

PRECAST | ISSUE ONE | 2020

1010946/P

GREAT STRUCTURES STAND TALL WITH SUPERIOR QUALITY, STRENGTH AND CONSISTENCY.

AfriSam High Strength Cement is developed for specialist concrete applications that require high early strength. Its durability, strength and workability make it the preferred product for construction and structural work. *Product specification dependent on area.

www.afrisam.com

Creating Concrete Possibilities

Precast • Issue 1 • 2020

Articles inside

CUSTOM-MADE PAVERS REVITALISE PEDESTRIAN WALKWAY IN CAPE TOWN

CAST-STONE COBBLES COMPLEMENT NEW CENTURY CITY PARKADE

PRECAST FACILITATES SHOPPING MALL OVER BUSY RAILWAY LINE

SA ARCHITECTURE SHAPES UP WITH DECORATIVE TILT-UP CONCRETE

JOHANNESBURG TWIN-DECK HIGHWAY BRIDGE REPAIR

ADVANTAGES OF CONCRETE PARKING AREAS

GREENER AGGREGATES FOR CONCRETE

PRODUCT OFF-PACKING SYSTEMS

SETTING UP AN EFFICIENT WALL PRODUCTION LINE

SOLUTIONS FOR THE PRECAST INDUSTRY

AWARD FOR TOILET DESIGN

VERSATILE PRECAST CONCRETE EQUIPMENT SHELTERS

ART AT THE LEONARDO

NEW LABORATORY PROVIDING SOLUTIONS

CONTRIBUTING TO SPORTS DEVELOPMENT

CONCRETE OFFERS SUPERIOR STRUCTURAL INTEGRITY

THE REAL THREAT OF USING SUB-STANDARD CEMENT

CONCRETE PIPING PROVIDES UNMATCHED DURABILITY

BUILDING A RISK-READY CONSTRUCTION INDUSTRY

SOCIAL MEDIA SOLUTIONS FOR THE PRECAST INDUSTRY

QUARRIES ESSENTIAL TO A SUSTAINABLE CONSTRUCTION INDUSTRY

PICP - A CASE FOR REGULAR PERFORMANCE TESTING AND MAINTENANCE

USAGE PHASE OF CONCRETE IS GREENER

PRECAST WALLING IS THE SAFEST OPTION