IMIESA May 2024

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IMESA The official magazine of the Institute of Municipal Engineering of Southern Africa

INFRASTRUCTURE DEVELOPMENT • SERVICE DELIVERY • ROADS • BUILDING • MAINTENANCE • ENERGY • WASTE

OF BUILDING COMMUNITY CEMENT & CONCRETE

Admixtures make concrete work

INFORMATION & COMMUNICATIONS TECHNOLOGY

Embracing better information management

MUNICIPAL FOCUS: NELSON MANDELA BAY

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INSIDE

VOLUME 49 NO. 04 MAY 2024

42 Regulars

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IMESA The official magazine of the Institute of Municipal Engineering of Southern Africa

Water & Wastewater

Editor’s comment President’s comment Index to advertisers

3 5 52

Tackling pollution key to water lettuce eradication

28

Getting value from smart water technologies

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INFRASTRUCTURE DEVELOPMENT • SERVICE DELIVERY • ROADS • BUILDING • MAINTENANCE • ENERGY • WASTE

Cover Story AfriSam – 90 years of building community

6

Information & Communications Technology

Mobility, nstallation.

ainerised asphalt mixing plant in ction that is fully enclosed in 100% nefits of our industry-leading range of ants include easy transportation and or both small and big projects.

OF BUILDING COMMUNITY CEMENT & CONCRETE

Admixtures make concrete work

Transforming infrastructure development in Africa with BIM Employing AI for safer structures

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INFORMATION & COMMUNICATIONS TECHNOLOGY

Convention annesburg

d 232

Embracing better information management

MUNICIPAL FOCUS: NELSON MANDELA BAY

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ON THE COVER AfriSam celebrates its 90th year in 2024. P6

Unlocking spatial insights for better planning: The start of the building data revolution (Part 1)

32

Municipal Focus: Nelson Mandela Bay Municipality Public-private partnerships are key to addressing SA’s water challenges

34

Environmental Engineering 14

Bitumen & Asphalt Hot (imported) bitumen on tap

Ha Mpiti to Sehlabathebe upgrade showcases excellence Concor moves into highly technical phases at Msikaba

16

Gabions enhance the final green design and protect

Renewable Energy & Electrification A green light for Lichtenburg and its community

18 20

38

Crushing & Screening Astec’s robust GT range proves its mettle

Retaining Wall Systems

Asphalt & Concrete Plants

Avoid disappointment and potential disaster.

Competent design, installation, and supervision are paramount

Pioneering Progress. Lintec & Linnhoff's commitment to African infrastructure development

PRECCA updates emphasise third-party accountability

36

Digital solutions that lower building footprints 39

22

Legal

41

42

Cement & Concrete Technology 24

Admixtures make concrete work

44

Waste Management

Corestruc scores another goal for precast construction

46

Laboratory support is crucial for good waste management

26

New Cape warehouse built with precast precision

48

AfriSam Roadstab Cement enhances durability

51

Pipe Systems Plastic pipes meet modern sewer demands BITUMEN & ASPHALT

Water storage and energy – a two-pronged approach

Regional & Town Planning

Roads & Bridges

16

Water Storage

36

27

ENVIRONMENTAL ENGINEERING

Spun concrete electrification poles add value 52

44

CEMENT & CONCRETE TECHNOLOGY

EDITOR’S COMMENT EDITOR Alastair Currie Email: alastair@infraprojects.co.za DESIGNER Beren Bauermeister CONTRIBUTORS Burgert Gildenhuys, Chetan Mistry, Danniel Kruger, Holger Rust, Lionel Van Tonder, Richard Matchett, Sibusiso Mjwara DISTRIBUTION MANAGER Nomsa Masina DISTRIBUTION COORDINATOR Asha Pursotham SUBSCRIPTIONS Email: distribution@infraprojects.co.za _________________________________________________ ADVERTISING SALES KEY ACCOUNT MANAGER Joanne Lawrie Tel: +27 (0)82 346 5338 Email: joanne@infraprojects.co.za _________________________________________________

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IMESA

Infrastructure ecosystems must be inclusive

F

our critical factors that need priority focus in South Africa right now are intensified investments in infrastructure (maintenance and new construction), power demand within the context of a Just Energy Transition, water security, and youth unemployment (plus unemployment in general.)

Tackling the first three will have a direct and indirect benefit in terms of skills development and job creation while stimulating positive socioeconomic growth.

As one of the most significant catalysts for change, world class infrastructure enables everything else. It attracts investment and is the hallmark of success for the world’s leading economies, China being among the most proactive as a developing nation.

Infrastructure for Good barometer

ANNUAL SUBSCRIPTION: R805.00 (INCL VAT) ISSN 0257 1978 IMIESA, Inst.MUNIC. ENG. S. AFR. © Copyright 2024. All rights reserved. _________________________________________________ IMESA CONTACTS HEAD OFFICE: Manager: Ingrid Botton P.O. Box 2190, Westville, 3630 Tel: +27 (0)31 266 3263 Email: admin@imesa.org.za Website: www.imesa.org.za BORDER Secretary: Celeste Vosloo Tel: +27 (0)43 705 2433 Email: celestev@buffalocity.gov.za EASTERN CAPE Secretary: Susan Canestra Tel: +27 (0)41 585 4142 ext. 7 Email: imesaec@imesa.org.za KWAZULU-NATAL Secretary: Narisha Sogan Tel: +27 (0)31 266 3263 Email: imesakzn@imesa.org.za NORTHERN PROVINCES Secretary: Zurika Louw Tel: +27 (0)82 322 5208 Email: np@imesa.org.za SOUTHERN CAPE KAROO Secretary: Henrietta Oliver Tel: +27 (0)79 390 7536 Email: imesasck@imesa.org.za WESTERN CAPE Secretary: Michelle Ackerman Tel: +27 (0)21 444 7112 Email: imesawc@imesa.org.za FREE STATE & NORTHERN CAPE Secretary: Wilma Van Der Walt Tel: +27 (0)83 457 4362 Email: imesafsnc@imesa.org.za

Developed countries logically already have well-established infrastructure networks in place. So their focus is more on improving efficiencies that enhance macro and micro economic needs within the context of the net zero agenda, while developing countries are focused on bridging the gaps that will serve as springboards for advancement.

In this respect, the 2023 Infrastructure for Good barometer developed by Economist Impact and supported

by Deloitte and Duke University’s Nicholas Institute for Energy, Environment & Sustainability showcases leading excellence, benchmarked against 30 countries. These are spread across the largest regional infrastructure markets globally. For the African region, the four countries included are Egypt, Kenya, Nigeria, and South Africa.

The barometer is based on five pillars, namely governance and planning; sustainable financing and investment; social and community impact; economic benefits and empowerment; and environmental sustainability and resilience.

As an extract from the report states, “…a country’s mix of policies, incentives and investments play a significant role in enabling infrastructure that improves quality of life and benefits society at all levels.” So that’s the broad end goal.

In the top ten overall are Canada (70,4 score), the United Kingdom (69,6), Germany, (67,7), Sweden (67,6), the Netherlands (66,6), Ireland (65,5), Norway (64,9), Switzerland (64,4), and the USA and Australia (both with an equal score of 63,7). In Africa, South Africa leads (score 52,1), followed by Kenya (46,4), Egypt (36,1) and Nigeria (32,8).

Economic and social objectives Three decades post the 1994 democratic transition have seen positive gains, but a major cash injection is now required to keep ahead of our burgeoning population growth from economic infrastructure (e.g., ICT, power, roads, water, and sanitation) and social infrastructure (such as housing, education, healthcare, and public transport) perspectives.

Given our relatively low tax base it’s increasingly clear that the public-private partnership model will be the essential ingredient. So, all stakeholders must buy into the policy framework.

As a snapshot of South African provincial performance, the Western Cape is a good example of how regional economic planning works. This is underscored by Statistics South Africa’s Q1 2024 Quarterly Labour Force Survey, which shows that the province has the lowest unemployment levels at around 21,4%, compared to the approximately 32,9% national average.

Fur thermore, the Western Cape created some 82 000 new jobs between Q1 2023 and Q1 2024, thanks to initiatives that include their Growth for Jobs strategy, SMME Booster Fund and the Alternative Energy Support Programme.

An end to loadshedding?

In all areas, electricity on demand is essential. In this respect, a positive win in Q2 2024 is the sudden halt in loadshedding. If sustained, it will send a highly encouraging message to investors that permanent progress has been made in line with government’s Energy Action Plan.

Achieving similar gains across other SOEs – like Transnet – combined with ongoing improvements in local government per formance, will fur ther increase private sector commitment. We need a unified response to grow South Africa in line with the UN Sustainable Development Goals.

Alastair

To our avid readers, check out what we are talking about on our website, Facebook page or follow us on Twitter and have your say.

All material herein IMIESA is copyright protected and may not be reproduced without the prior written permission of the publisher. The views of the authors do not necessarily reflect those of the Institute of Municipal Engineering of Southern Africa or the publishers.

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OF BUILDING COMMUNITY CEMENT & CONCRETE

Admixtures make concrete work

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INFORMATION & COMMUNICATIONS TECHNOLOGY

Embracing better information management

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What South Africa’s ranking shows is that we’re on the right path: we just need to accelerate our programmes, leveraging infrastructure to close poverty and inequality gaps.

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PRESIDENT’S COMMENT

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MUNICIPAL ENGINEERING AND ASSET MANAGEMENT Within the infrastructure space globally, proactive asset management is the backbone of effective service delivery. It starts at the planning stage by optimising as-built structures to achieve the lowest possible carbon footprint during new construction, with an allied upfront focus on the best way to maximise their functional life in terms of operations and maintenance (O&M).

T

his is essential in achieving the return on investment required by asset owners, ensuring that the preplanned lifecycle O&M budgeting checklist syncs with the approved design and actual installation. The latter is crucial because asset management and finance are equal partners in executing the delivery process.

Whether it’s a greenfield or an existing brownfield site, the same principles apply. In terms of the latter, the need is even greater since older structures – like buildings, roads, or treatment works – need to be constantly revisited in terms of their current health status – both from O&M and potential safety perspectives.

That’s why an up-to-date and accurate asset management register must always be in place.

It’s not an option: this is a legal requirement for all government entities and making it happen in practice is an essential component of ensuring a well-functioning infrastructure platform that enables positive socioeconomic advancement in a currently constrained fiscal environment.

Without accurate asset management records and monitoring – especially at local government level, as the final delivery point – maintenance will become negatively reactive, and cost far more than necessary to repair when sudden failures like pipeline bursts occur due to ageing infrastructure.

Opportunities to upscale The downstream benefits of planned asset management interventions are proven. There’s also a prime opportunity to implement modern technologies for existing (and mature) assets that help us get closer to net zero.

Examples include recycled asphalt and the incorporation of plastic waste aggregate for road rehabilitation. Another example in the water and wastewater segment is the employment of energy efficient pumps to drive down process costs. Plus, there are biogas powered genset opportunities derived from wastewater processes to run treatment plants to

a greater or lesser degree, with opportunities to wheel surplus energy back into the grid.

IPWEA International Public Works Conference Developed or developing, the objective for all countries must be on best practice asset management outcomes. This was a central theme at the recent Institute of Public Works Engineering Australasia’s (IPWEA’s) 2024 International Public Works Conference in Melbourne, Australia, between 29th and 2nd May. Australia, like South Africa, is a member of the International Federation of Municipal Engineering (IFME) and I attended as IMESA President and South Africa’s board member.

Just about everything was covered from landfill optimisation to street lighting, greener roads, geographic information systems, public transport and transportation, as well as how digitalisation can and will enhance future construction projects by harnessing better information modelling, the logical evolution of Building Information Modelling. The central theme throughout tied in with a major emphasis on integrated infrastructure asset management.

One of the case studies showcased the work of Melbourne City Council in implementing effective digital infrastructure interventions. This includes a 3D electronic map of the city that incorporates anticipated flood line events that can be lit up on a disaster management wall panel at the touch of a button.

As a coastal settlement, Melbourne has also had to prepare for rising sea levels, alongside the more immediate issues of recurring flooding due to climate change impacts. Engineered responses include the widening and deepening of the Yarra River, which winds through the city, to accommodate greater water volumes.

Plus, like most towns and cities worldwide,

A perspective of the city of Melbourne, host city for the Public Works Engineering Australasia’s (IPWEA’s) 2024 International Public Works Conference, held between 29th and 2nd May 2024

Melbourne, which has a population of around 5,2 million, continues to experience increasing levels of urbanisation, stimulating demand for accommodation and related services. To reduce traffic congestion, part of the response includes a sophisticated public transport network comprising buses, trains and electric trams that can all be accessed via a single card payment system. The city’s tram network comprises some 250 km of double track and is believed to be the largest of its kind worldwide, with some 1 700 tram stops.

The way forward A major takeaway for IFME delegates – spread across diverse geographic regions that include members from Africa, Asia, Europe, the Middle East and North America – is that all countries need to invest more in asset management at local government level. In this respect, Australia is a shining example.

To enable this in South Africa, ongoing specialist training must be provided for engineering and allied built environment practitioners, as well as their financial counterparts. Otherwise, we will struggle to keep pace with infrastructure demand within the context of a growing population. The latter increased by 19,8% between 2011 and 2022 to around 62 million according to the 2022 Census and is set to keep on growing, placing renewed emphasis on current and future planning scenarios.

Sibusiso Mjwara, PrTechEng, MIMESA, MSAICE, MWISA, MIPET

IMIESA May 2024

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COVER STORY

Celebrating its 90th year during such challenging times for construction in South Africa cer tainly highlights AfriSam’s legacy of resilience and its commitment to Africa’s development, according to Sales & Marketing Executive Richard Tomes.

O

ur success over the years demonstrates not only our world class standing but equally how we respond to the changing needs of our customers and the broader community – in good times and hard times,” says Tomes. “We are proud that our contribution ranges from the highest quality construction materials through to affordable solutions for emerging contractors, as well as targeted social responsibility and sponsorship initiatives that build cohesion in our society.”

AfriSam’s legacy began in 1934 as the Anglovaal Por tland Cement Company, South Africa’s second cement company.

Impor tantly, though, it was the first to diversify its offerings into other construction materials. This included readymix concrete through the company Pioneer Concrete and aggregate stone through Hippo Quarries.

The evolution of the business saw its name change to Anglo Alpha in 1937 and Alpha Ltd in 1996.

AfriSam’s targeted social responsibility and sponsorship initiatives have built cohesion in our society

AfriSam – 90 years of building community

AfriSam supplied cement to the Lesotho Highlands Water Project in the 1980s and 1990s and has also started supplying the second phase of this project

Global attention “Steady growth made us one of the largest suppliers of construction materials for many years, also delivering cement to our southern African neighbours,” he says.

“Our standing in the industr y meant that we attracted the interest of global players when our economy opened up with the advent of democracy in 1994.”

Richard Tomes, AfriSam Sales & Marketing Executive

6 IMIESA May 2024

This led to the company becoming part of Holcim, the world’s largest cement producer.

Even then, AfriSam had built a world class foundation, with its Ulco cement plant ranking as the third best performing operation in the global Holcim group. The AfriSam brand itself was born after an historic Broad Based Black Economic Empowerment (BBBEE) transaction in 2008.

“The company could already boast some of the world’s best expertise in the sector, being involved in mega-projects such as the Lesotho Highlands Water Project in the 1980s and 1990s,” he says. “This investment in

COVER STORY

skills has been a pillar of AfriSam’s success and longevity, and remains a focus for us even during economic downturns.”

Iconic structures As a result, AfriSam has been associated with some of South Africa’s most iconic structures – signifying its direct contribution to the infrastructure on which the country’s growth has been built. These include the 50-storey Carlton Centre in Johannesburg’s city centre, the Nelson Mandela Bridge and the Gautrain project.

“This has earned us the most trusted name in South Africa’s readymix space,” he argues.

“What is significant about this today is that the larger contractors have been forced to slim down in recent years – so they often do not have their own concrete technologists in-house.”

This makes its biggest customers increasingly reliant on AfriSam’s technical exper tise in cement and concrete, which is vital for ensuring compliance with project specifications so that structures last for their full expected lifespan and beyond.

Succession, training and upgrading of skills take place continuously alongside research and development, he says, in the knowledge that future economic growth depends upon it.

Iconic projects include the Nelson Mandela Bridge

Reducing carbon emissions AfriSam’s depth of expertise has also been crucial in addressing global imperatives such as climate change and energy efficiency, Tomes points out. The company has been a leading force in finding new ways to reduce the carbon emissions associated with cement production.

“We were the first company to launch an eco-cement, based on our research and experimentation with the use of extenders to reduce clinker content,” he explains. “From an

Customers have become increasingly reliant on AfriSam’s technical expertise in cement and concrete

early stage, this became a cornerstone of our commitment to ‘planet’ in our ‘ People, Planet and Performance’ principles.”

Beyond its own corporate imperatives, AfriSam’s exper ts have taken a leading role in organisations like the Association of Cementitious Material Producers (ACMP) to advance efforts by the sector to ensure sustainability for future generations.

Support in tough times AfriSam has introduced a cost effective readymix product, Starmix

Reflecting on the ways that AfriSam develops and adapts its product range to suit the times, Tomes points to the company’s ability to serve customers and the country when the economic climate is tough.

“It is perhaps especially in times like now, when there has been sustained pressure on the economy and livelihoods, that companies like AfriSam need to prove their mettle,” he says. “For instance, our R&D has produced cost effective concrete solutions like Starmix, which is ideally suited for the building industr y. It can, however, also be ordered in small quantities, making it ideal for the residential builder as well.”

IMIESA May 2024

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COVER STORY

AfriSam’s long history has also been characterised by its social responsibility efforts

In a countr y beset by housing shor tages, urban migration and unemployment, this allows small building works to continue as a basic step in uplifting people’s lives, he says.

“Most impor tantly, this work can carr y on without compromising quality, and still prioritising our commitment to a lower carbon footprint for the generations that will follow us,” he emphasises. “This goes hand-in-hand with the suppor t we provide to emerging and small builders through training and knowledge sharing.”

AfriSam provides support to emerging and small builders through training and knowledge sharing

www.afrisam.co.za

8 IMIESA May 2024

Cohesion and unity Beyond the worksite, AfriSam’s long history has also been characterised by its social responsibility, aimed at suppor ting the broader community in their efforts to create a better future. Spor t has always been central to social cohesion, he says, and remembers AfriSam sponsoring an Orlando Pirates team captained by the legendar y Jomo Sono.

“More recently, we were proud to be a par tner to the Springbok rugby team as they prepared for – and finally won – the

latest Rugby World Cup in France,” he says, highlighting how success builds the national psyche and the confidence of citizens in the future. The range of other investments includes youth employment initiatives and various community activities.

Looking ahead at projects that signify better times ahead, Tomes notes that AfriSam will be contributing to two of the projects in the latest phase of the Lesotho Highlands Water Project – the Polihali Dam and the 34 km transfer tunnel. From this year, a total estimated supply of 207 000 tons of cement will be supplied over the lifespans of both projects, delivered from AfriSam’s Ulco plant.

“As a responsible construction materials producer, we comply with Social and Labour Plan regulations, but our vision and actions go well beyond that,” concludes Tomes. “With our 90 years in business, we exemplify the value of stable businesses that actively develop skills and sustain jobs, retaining the groundwork on which the economy can grow.”

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Delegates attending the BIM CoDE•SA 4 workshop in April 2024

TRANSFORMING INFRASTRUCTURE DEVELOPMENT IN AFRICA WITH BIM Better Information Management (BIM) is revolutionising the way we design, construct, and manage infrastructure worldwide. As opposed to the traditional understanding of Building Information Modelling, BIM today emphasises comprehensive, accurate, and actionable information management throughout the entire lifecycle of a project.

BIM is not a software. It is a methodology, a way of working. By Richard Matchett

I

n this ar ticle, we delve into the significance of BIM for Africa’s infrastructure development, its growing role in managing municipal infrastructure, and the critical importance of better information management. We also highlight the challenges and opportunities of BIM adoption, the relevance of SANS 19650, and the need for upskilling. Lastly, we explore the initiatives of BIMcommUNITY.Africa and the future of BIM in Africa.

Overview BIM is a process that provides comprehensive information management across the entire lifecycle of a project. It goes beyond 3D modelling during the design of a project to include operational value creators like datadriven decision making, risk management, and sustainability. Internationally, there is a shift toward understanding BIM as Better Information Management rather than just Building Information Modelling. This shift is crucial as accurate information management becomes essential for planning, designing, constructing, and maintaining infrastructure

10 IMIESA May 2024

effectively. BIM is not just a “nice-to-have”; it’s becoming a “must-have.”

Due to growing population numbers, the challenges of climate change, and migration from rural to urban areas, managing municipal infrastructure demands proactive planning, especially in Africa, where the construction industry is rapidly evolving. BIM enhances project delivery by creating a unified data environment where architects, engineers, contractors, and owners collaborate seamlessly. This in turn reduces communication lag and fosters more proactive collaboration in project teams, thereby promoting better project outcomes.

Better information management leads to better planning, better designs, and ultimately better maintenance, which is critical in the South African context of limited budgets, growing populations, and aged infrastructure.

IM in managing municipal B infrastructure internationally Globally, municipal authorities are turning to BIM to ensure that infrastructure projects are designed and executed with precision, while

also enabling efficient asset management over their lifecycle.

In the UK, the government’s BIM Mandate has made BIM mandator y for all public infrastructure projects, ensuring that every public infrastructure project has accurate data for decision making. Similarly, in the United States, BIM is used extensively in federal projects, with cities like New York incorporating it into urban planning.

In South Africa, cities like Cape Town are leading the way towards adopting BIM for managing their municipal infrastructure. Cape Town’s Transport and Urban Development Authority will leverage BIM to improve the planning, design, and maintenance of public infrastructure. By implementing BIM standards and processes, the city will be better equipped to handle urban challenges and ensure the sustainability of its infrastructure.

Poor infrastructure management is a drain on the fiscus and also a danger to a country’s citizens. BIM provides municipalities with the tools to proactively address these challenges, ensuring accurate information is readily available for maintenance and emergency response.

Ultimately, better information leads to better planning, better designs, and better maintenance, helping municipalities save time, money, and prioritise citizen welfare.

ANS 19650, BIM Mandate, and S National Annex The South African National Standards (SANS) 19650 series is a set of standards that align with the international ISO 19650 series, providing guidelines for information

INFORMATION & COMMUNICATIONS TECHNOLOGY

management using BIM. It defines the principles and requirements for effective information management throughout the lifecycle of built assets, from conception to operation. SANS 19650 includes: - SANS 19650-1: Concepts and principles of information management.

- SANS 19650-2: Delivery phase of information management.

- National Annex: South Africa-specific guidelines for BIM implementation (In progress).

The BIM Mandate in South Africa, driven by the National Department of Public Works and Infrastructure, requires the use of SANS 19650 standards in public infrastructure projects.

BIMcommUNITY.Africa has been advocating for the adoption of these standards and is actively involved in the BIM CoDE•SA initiative.

BIM CoDE•SA is a collaborative and agnostic platform, bringing together government officials, industry professionals and academia to discuss and shape BIM adoption policies. By adopting SANS 19650, South Africa aims to standardise BIM processes, enhance collaboration, and improve project delivery.

Ignoring these standards means missing out on the efficiency and collaboration that BIM offers. Municipalities and private developers must understand and embrace SANS 19650 to remain competitive and deliver highquality infrastructure.

he backbone of intelligent T infrastructure BIM is the foundation for intelligent infrastructure, which forms the backbone of an efficient and functioning state. By creating a unified digital environment, BIM provides accurate, real-time data that enables stakeholders to make informed decisions throughout a project’s lifecycle. And beyond into asset management.

In the context of South Africa’s limited budgets, growing populations, and aging infrastructure, better information management allows for proactive planning, intelligent designs, and effective maintenance. This proactive approach helps municipalities: • Identify risks early, minimising costly delays and errors.

• Optimise resource use, saving money and reducing waste.

• P rioritise citizen needs by ensuring infrastructure is safe, sustainable, efficient and responsive.

BIM also fosters collaboration, innovation, and intelligent planning, which are essential in solving Africa’s infrastructure challenges.

When information is accurate and accessible, stakeholders can: • Visualise complex projects in 3D. • Simulate different design scenarios.

• Detect potential clashes before construction begins.

Without accurate information, projects suffer from delays, budget overruns, and safety hazards.

Upskilling and preparing for BIM Adopting BIM requires a skilled workforce capable of leveraging its potential. However, the current skills shor tage remains a significant challenge for BIM adoption in Africa.

To address this, upskilling programmes and training initiatives are essential.

ey steps to get ready for BIM K (BIM Fit): 1. Education and training: • Enroll in BIM certification courses and workshops.

• Participate in webinars and conferences to stay updated on BIM trends.

• J oin professional networks like BIMcommUNITY.Africa for peer learning.

2. Adopting BIM standards: • Familiarise yourself with SANS 19650 and ISO 19650 standards.

• Implement these standards in your projects to improve information management.

3. Collaborative platforms: • Invest in cloud-based BIM collaboration platforms.

• Encourage interdisciplinary collaboration by creating shared digital environments.

4. Government support: • Advocate for government policies that support BIM adoption.

• Collaborate with public agencies in implementing national BIM mandates.

5. Upskilling programmes: • P rofessional bodies and institutes can prepare their members by developing training that’s specific to BIM methodologies and information management.

• Organisations like IMESA can partner with BIMcommUNITY.Africa to develop specialised training programmes.

Ignoring BIM means falling behind in delivering efficient, sustainable infrastructure. By prioritising upskilling, organisations can harness BIM’s full potential and contribute to Africa’s infrastructure transformation.

Future of BIM in Africa The future of BIM in Africa is promising. As the construction industry embraces digital transformation, BIM will become integral to infrastructure development. Continued collaboration among industry stakeholders, government support, and training programmes will drive BIM adoption.

In the coming decade, we envision BIM being standard practice in public infrastructure projects and private developments alike. The integration of BIM with emerging technologies like artificial intelligence and the Internet of Things will further enhance its value, creating smart, sustainable infrastructure across the continent. BIM lays the foundation for Digital Twins and Smart Cities.

Conclusion BIM is more than just a tool (and definitely not a software); it is a catalyst for change in Africa’s construction industry. By enhancing collaboration, improving sustainability, and streamlining project deliver y, BIM is transforming the way we build. However, realising its full potential requires concerted effor ts to address challenges and unlock opportunities.

BIMcommUNITY.Africa remains committed to leading this transformation, and we call on all industry stakeholders to join us in advocating for BIM adoption. Together, we can build a sustainable, efficient, and innovative infrastructure future for Africa.

Email angela@bimcommunity.africa for further information.

Richard Matchett, Digital Practice Lead, Zutari

IMIESA May 2024

11

INFORMATION & COMMUNICATIONS TECHNOLOGY

EMPLOYING AI FOR SAFER STRUCTURES Structural health monitoring (SHM) specialists, Move Solutions, has recently added the MyMove IoT platform to their technology suite for the building and civils segments, which is now available in South Africa via its distributor, TANDM.

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2

o predict structural health issues before they become critical, MyMove uses ar tificial intelligence (AI) to transform vast and complex data into easily understandable information and uses machine learning to identify subtle changes or anomalies in structures.

“This technology will enhance the safety and durability of structures, as well as reduce maintenance costs by addressing problems in the first stages,” says Ambra Scotolati, marketing strategist for Move Solutions.

3 “It also allows for an understanding of the reasons behind cer tain issues and the immediate detection of anomalies for timely decision-making.”

In addition, the real-time function of MyMove removes the time-consuming, costly, and sometimes inadequate manual and periodic inspections that the industry currently relies on. With the information MyMove gleans from historical data, AI algorithms can accurately distinguish between normal fluctuations and genuine structural anomalies. This level of accuracy enables

industries where structural integrity is key to prevent catastrophic failures and enhance public safety on structures that include bridges, railways and high-rise buildings.

“Real-time insights and anomaly detection have been a challenge that the broader building and construction industry in South Africa has faced.

The integration of AI in SHM is a paradigm shift in how we approach the longevity and safety of infrastructure. We are excited to be introducing this cutting-edge technology to the South African market,” says Elton Murison, director at TANDM.

GAUTRAIN VIADUCT STUDY 1 Installation of the Move Solutions systems for the monitoring programme 2 The range of sensors employed, as well as their positioning for the study 3 Real-time and long-term monitoring of a Gautrain rail viaduct in Pretoria has proven crucial in maintenance planning and infrastructure health assessment

4 Move Solutions sensors installed on the railway tracks

4 12 IMIESA May 2024

INFORMATION & COMMUNICATIONS TECHNOLOGY

Case study A recent project using Move Solutions technologies entails the real-time and longterm monitoring of a Gautrain rail viaduct in Pretoria. Commencing in July 2022, this pioneering project has been led by Professor Hannes Grabe, Head of the Department and Chair of Railway Engineering at the University of Pretoria.

The railway sector in South Africa is on the cusp of a transformative era, with Transnet objectives and government investments bolstering its development. In support, the University of Pretoria, in collaboration with key industr y stakeholders, is pioneering advancements in this field. This includes the university’s establishment of its Engineering 4.0 campus, focusing on transportation and railway engineering.

Monitoring objectives The main goal of the project was to monitor deflection and acceleration responses on the viaduct for effective maintenance planning

and performance management. By choosing the track transition from an embankment to a viaduct and a nearby control site, the project aimed to establish a comparative analysis of train dynamics and track response at these adjacent locations.

Hardware and software solutions The project included the following Move Solutions sensors: • Dynamic displacement sensors for vertical sleeper deflection and vertical deflection of the viaduct, and • Accelerometers to measure the sleeper acceleration.

These sensors, leveraging LoRaWAN communication, transmit data to the Move Solutions IoT platform, ensuring continuous and reliable monitoring. The system employs advanced diagnostic tools like Frequency Domain Decomposition, Displacement Density Probability function, and Fast Fourier Transform. Alarm triggers are set for deflection exceedances (sleeper/bridge/

rail deflection), temperature exceedances (indicative of rail kickouts or breaks), acceleration exceedances (from rolling stock), door status, and security breaches.

Project outcomes Since the baseline date in July 2022, the system has been functioning exceptionally, providing invaluable data. Key findings include: - A clear correlation between temperature and deflection on an event scale - A long-term downward trend in vertical deflections and accelerations - While real-time monitoring with reliable LoRaWAN communication and specialised trending has proven crucial in maintenance planning and infrastructure health assessment.

“This project demonstrates the efficacy and the need of advanced monitoring technologies in the rail industry, paving the way for smarter, safer, and more efficient railway systems,” Murison concludes.

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TOWN & REGIONAL PLANNING

UNLOCKING SPATIAL INSIGHTS FOR BETTER PLANNING PART 1

THE START OF THE BUILDING DATA REVOLUTION

The built environment hasn’t escaped the ever-improving ability of technology to unlock data at an unprecedented rate. The challenge has been the general inability of built environment professionals to keep pace. However, enhancements in efficient information access now holds immense potential for revolutionising planning and decision-making in South Africa. It’s time to get onboard. By Burgert Gildenhuys* foundation for the Eskom Spot Building Count dataset. With annual updates until 2013, this dataset grew to over 13 million points. While the initial data quality had challenges, it signalled progress in spatially mapping building locations and densities.

In later iterations, remote sensing and collaboration with specialised companies improved the data quality and coverage, reinforcing the importance of technology in this evolution.

Dwelling frames: linking attributes to points FIGURE 1: The case study area

StatsSA entered the scene in 2012 with the Dwelling Frame dataset. In a significant step for ward, this dataset added attributes like dwelling types, although it focused primarily on dwellings, leaving commercial and industrial structures uncharted.

The process initially used manual capturing, but the later data releases started to incorporate commercial data. This sometimes necessitated the masking of detail point data to protect the commercial interests of the data providers. This may be why StatsSA only released the 2020 data set at an enumerator level.

Building footprints: a leap into precision

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n this series of three articles, we will take you on a journey through the evolution of building data, from humble attributeless dots on aerial photographs to the powerful insights derived from opensource data via remote sensing and artificial intelligence. This is Part 1, which provides important historical context.

Let’s walk through this process using Sandton CBD, Alexandra, and the Wynberg industrial area to illustrate this evolution from day one. This area

14 IMIESA May 2024

FIGURE 2: Eskom Spot Building counts 2013

includes the highly developed area of Sandton CBD, the Wynberg industrial area, Alexandra as an old established township, and the higher income low residential area adjacent to them.

Building points: a humble beginning In 2006, Eskom embarked on a mission to record the locations of buildings across South Africa.

Using manual methods and aerial photography, they assigned points to buildings, creating the

The game-changer arrived in 2021 when Microsoft Bing made worldwide building footprints publicly accessible (https://www.microsoft.com/en-us/ maps/bing-maps/building-footprints ). For the first time, these footprints were available as polygons, offering area measurements for each structure.

Google followed suit with a similar dataset, albeit with some variations in capturing larger buildings.

This evolution in data granularity provided more accurate insights into building characteristics. The third version of the Google data set was released in May 2023. (https://sites.research.google/ open-buildings/)

TOWN & REGIONAL PLANNING The beginning of a new era In just over one and a half decades, we have moved from a tedious and laborious manual process of capturing building structures as little dots to public domain data sets available for any global location, showing the size and two-dimensional characteristics of almost every existing building. In September 2023, the consolidated Google V3 Open Buildings and Microsoft’s most recent Building Footprints comprised a staggering 2 534 595 270 footprints.

From uncertainty and incomplete data, the world has changed to a data overload, and there are opportunities for precise measuring and the opportunity to analyse beyond our imaginations.

The question is whether we, as built environment professionals, will be able to utilise these opportunities, or will we sit back in our comfort zone and watch as the world of opportunities passes us by?

In Part 2 of this series, we will show the availability of temporal data and the threedimensional attributes of building data that are leading us to explore service delivery demands and infrastructure planning at levels that were not previously possible.

FIGURE 3: StatsSA Dwelling Frame 2018

*Pr. Pln, MIAM (London), ILGM, B(TRP), BAdmin (Municipal Administration)

FIGURE 4: Microsoft Bing building footprints

ABOUT THE AUTHOR

FIGURE 5: Google building footprints v1

Burgert Gildenhuys is the founding Director of Spatial Data Services Africa NPC. This non-profit organisation is dedicated to promoting and supporting government and business in better understanding and utilising data and digital technologies.

The objective is to promote spatial transformation and strengthen development and policy outcomes to benefit the poor and vulnerable.

Email: burgert@sdsafrica.net www.sdsafrica.net FIGURE 6: Google building footprints v3

IMIESA May 2024

15

BITUMEN & ASPHALT

Not too long ago, South Africa expor ted bitumen.

Today we rely heavily on bitumen impor ts.

Bitumen tanks, shown here, leased by RASA from FFS in Cape Town Harbour since 2021

Hot (imported) bitumen on tap

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n the few shor t years since South African refineries star ted closing their bitumen operations, the South African asphalt industry has worked with importers to come up with sustainable alternatives. It seems that win-win solutions have been developed between the asphalt manufacturers and bitumen importers.

Niel du Toit, Bitumen Operations Manager at AECI Much Asphalt, Southern Africa’s largest

asphalt producer, recalls the early bitumen imports after three of only four local bitumen refineries shut down their bitumen operations in quick succession. “The market opened for imports, creating the new challenge of finding storage for the bitumen that had to be emptied out of a ship within a few short days before its departure from dock.”

AECI Much Asphalt, along with other manufacturers, hastily came up with

shor t-term, expensive, storage solutions.

But as the industr y recovers from the Covid hiatus, a ship to site scenario has become increasingly unsustainable.

Bulk storage Rubis Asphalt South Africa (RASA) is one of two companies that have invested in bulk bitumen storage in South Africa. “Instead of buying product in a ver y small timeframe

The three new bitumen storage tanks developed by FFS and leased by RASA at Maydon Wharf in Durban

16 IMIESA May 2024

BITUMEN & ASPHALT

and having to store, then heat and transpor t it again to the plants’ requirements, loading out of these facilities is easy and only as and when required. In a nutshell, it is basically hot bitumen on tap,” says du Toit.

RASA has operated storage tanks in Cape Town for almost three years and the industr y welcomed the addition of the company’s new Durban storage facility this year. These facilities accept bitumen straight from a vessel into the bulk tanks, from where asphalt manufacturers collect by truck.

Rubis Asphalt South Africa (RASA) is par t of Rubis Asphalt Middle East (RAME), the bitumen division of Rubis Energie, a listed company on the Paris Stock Exchange. RASA is the sister company to Easigas, the leading LPG supplier in Southern Africa.

Mark Simonsen, Deputy General Manager, elaborates that RASA delivered its first impor ted bitumen to South Africa in September 2021. “Until this year we have supplied directly into bulk bitumen tanks in the Cape Town por t, while Durban was supplied on a ‘ship to truck’ basis. However, early this year we opened our own bulk storage tanks in Durban, so we no longer supply direct from ship to truck.”

Own fleet He adds that the product is sourced mainly from established refineries in Europe, using repeat sources to ensure quality and consistency of supply. “We focus on 50/70 grade bitumen but can also impor t different grades on firm orders and detailed planning with our customers.

“We have longstanding relationships with our main supply sources and transpor t the product in our own fleet of vessels to strategic storage facilities in all the major por ts where we operate.”

RASA leased two bitumen tanks with a combined capacity of some 4 800 tons from FFS in Cape Town in 2021 and this successful par tnership led to a long-term lease which would see FFS investing in a large storage facility in Maydon Whar f, Durban. The first phase of this development involved three bitumen storage tanks totalling about 7 500 tons, which are now active, with an additional 3 000 tons to follow in Phase II of the FFS development.

AECI Much Asphalt has been a customer in both Durban and Cape Town since day one. “RASA had the foresight to invest in significant storage capacity in both Cape Town and Durban. The fact that the company runs its own vessels makes the supply chain even more reliable and competitive,” says du Toit.

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Quality product “As a customer we’ve requested a quality product that is acceptable to both the premix and the modified industr y, and RASA has committed to do just that. Having struggled with impor ting, storing, heating, and loading product out of bitutainers for the last few years, we find this offering just as easy, and sometimes even more so, than loading hot bitumen on tap at a refiner y,” he adds.

“The asphalt industr y has geared up to take advantage of the upturn we are seeing in asphalt road construction and maintenance. Simple, high quality, consistent bitumen solutions are essential,” du Toit concludes.

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YEARS

ROADS & BRIDGES

Paving operations in progress at km 40,01

Ha Mpiti to Sehlabathebe upgrade showcases excellence The upgraded Ha Mpiti to Sehlabathebe road traverses Lesotho from east to west and forms par t of a future ring-road that will link the southern town of Qachas Nek with Thaba Tseka.

The revitalised route provides much improved connectivity for local communities, while boosting tourism investment in Sehlabathebe National Park – a world heritage site.

The revitalised Ha Mpiti to Sehlabathebe route provides all-weather surfaced road access for 12 villages to Qachas Nek, the main town in the district (with a hospital and commercial centre) and from there to the capital city of Maseru

PROJECT INFORMATION/ STATISTICS • Client: Roads Directorate, Ministry of Public Works and Transport, Kingdom of Lesotho • Funding: EXIM Bank of China (concessional loan) and the Government of Lesotho • Location: Qachas Nek District, Kingdom of Lesotho • Scope: the upgraded 91 km two lane road shortens driving time from Ha Mpiti to Sehlabathebe from 4 hours to 1,5 hours • Asphalt quantities: 86 000 tons

18 IMIESA May 2024

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he mountainous environment is characterised by steep river valleys which cross an ever-changing geology of sedimentar y rock layers until it climbs into the basaltic rocks. The Ha Mpiti to Sehlabathebe section starts at approximately 1 700 m and climbs to 2 400 m above sea level.

Depending on the altitude, the climate in the highlands includes a temperature range from an average minimum of 5°C (July) to an average high of 28°C (January/December). The minimum temperatures often fall to below 0°C in the winter months in the higher altitudes.

The project scope has entailed the upgrading of a 91 km rural road from a gravel to a surfaced (asphalt) standard, and included an economic feasibility study, environmental and social impact assessment, preliminary and detail design, tender documentation and supervision of the building contractor.

SMEC was initially appointed to under take feasibility studies and design in 2012. The design was completed in 2014. The client negotiated a contract price with the contractor (Qinjian Group Co.,Ltd) in 2018 and construction commenced on 23rd Januar y 2019. Practical completion was achieved in March 2024.

Countering freeze-thaw cycles and frost heave The pavement design is adapted to resist the effect of freeze-thaw cycles and frost heave. Using the Lesotho pavement design guidelines, the depth of frost penetration was estimated and frost resistant materials were specified for layers anticipated to be affected by frost penetration. The base layer was specified as a bitumen stabilised crushed stone material where the presence of bitumen makes the layer more resistant to water ingress.

ROADS & BRIDGES

The mountainous environment is characterised by steep river valleys that needed to be catered for in the upgraded road design

Stream crossing at km 22

The subbase was specified as a crushed stone material containing less than 3% of material finer than 0,02 mm. This specification is to reduce capillary action in the material from “sucking” moisture into the subbase from the supporting subgrade. Both specifications minimise the presence of excess moisture entering these upper pavement layers during the pavement design life, which, during repeated cold cycles falling below 0 °C, would freeze, expand and cause these layers to heave and lose shear strength when the temperatures increase again.

Throughout the project, the main contractor created employment opportunities for Lesotho nationals which increased up to 793 people

(686 men and 107 women) in Februar y 2023. These included 350 unskilled labour positions. The balance were skilled labour, operators/drivers, plus super visors and management personnel.

SMEC has provided value to the Lesotho Roads Directorate from inception through to the construction phase of the project.

All weather access The Ha Mpiti to Sehlabathebe road now provides all-weather surfaced road access for 12 villages to Qachas Nek, the main town in the district (with a hospital and commercial centre) and from there to the capital city of Maseru.

“SMEC has been privileged to have played a key role in the design and implementation of this large and challenging road project in the mountain kingdom of Lesotho,” says Rob Archibald, SMEC South Africa Technical Principal and Project Director.

“We have built a great relationship with the client team over the years since the inception of the project, a good working relationship with the Chinese contractor, and a strong supervision team by combining a few experienced South African engineers with very capable engineers and technicians from Lesotho. We look forward to continuing these professional relationships on future projects in Lesotho.”

ROADS & BRIDGES

The pylon spires of South Africa’s Msikaba Bridge mega project are on their way up, soon to tower almost 130 metres high at each side of the near 200 metre deep river gorge

Concor moves into highly technical phases at Msikaba

The band is starting to play louder at the aweinspiring Msikaba Bridge project, according to Concor’s Laurence Savage, Project Director of this pioneering structure.

Once completed the two pylon spires for the Msikaba Bridge will create two elegant pinnacles that are bound to inspire admiration from travellers and communities for many miles around

The flagship Msikaba Bridge near Lusikisiki in the Eastern Cape is now reaching a more technically challenging phase

20 IMIESA May 2024

The bridge is being built from the north and south banks of the gorge and comprises two identical “halves”, each spanning 290 metres, which will meet mid-point over the gorge

T

he Msikaba Bridge forms part of the South African National Roads Agency Limited’s (SANRAL’s) N2 Wild Coast project and is being constructed by the CME JV, a partnership between Concor and MECSA, both 100% black owned Grade 9CE South African construction companies.

“The last two years have been spent completing the four 21 000 t anchor blocks and progressing the elegant bridge pylons on each side of the gorge,” explains Savage. “We are now entering some exciting but technically challenging phases.”

The first of these is the post-stressing of the anchor blocks, to ensure the transfer of load exerted by the stay cables is well distributed through the blocks. Embedded 14 metres deep into each block, the post-stressing is profiled as a large ‘U’ shape to mobilise the dead mass of the anchor block being pulled up by the stay cable at the top.

He highlights that the post-stressing option is a modern and efficient strategy that reduces the need for reinforcement steel – which could have congested the blocks and made it difficult for the concrete to fill all the voids. The locally procured post tensioning strand cables at each of the 17 anchor points in each block are stressed up to around 500 t by a specialist company. The process is expected to take two to three weeks for each anchor point.

Pylon inserts “The next major step will be installing pylon inserts into the pylon’s structure as it rises above the 86 metre mark,” he says. “There are 17 inserts for each pylon; these are steel rings weighing 8 to 10 t each, which are concreted into place one after the other until the pylon reaches a height of about 122 metres.”

The pylon inserts are used as the anchors from which the cables run as back-stays to the anchor blocks, and as fore-stays to the bridge deck. However, Savage notes that not all the inserts have to be in place before the launching of the deck can begin. Careful planning will allow the deck launching – itself a highly technical task – to commence after the first five inserts are installed, which is likely to be in the second half of 2024.

Ladder deck Another demanding aspect of the bridge’s latest phase will be the construction of the ladder deck. Being the first steel deck segment of the bridge, the ladder deck is to be cast in concrete into the foundation of the pylon and will be the largest continuous pour on site.

“We will cast 700 m3 of concrete in a single pour, with a very strong 65 MPa mix,” adds Savage. “This will also demand a high density of reinforcement steel, weighing 160 t.”

RETAINING WALL SYSTEMS

AVOID DISAPPOINTMENT AND POTENTIAL DISASTER

COMPETENT DESIGN, INSTALLATION, AND SUPERVISION ARE PARAMOUNT Disappointment with the outcome of construction projects, including segmental block retaining walls, may manifest itself in two ways. The first is aesthetics, due to unattractive, sloppy finishes or the use of sub-standard materials; the second is structural defects due to factors like poor design, insufficient supervision, non-compliance, bad quality control and maintenance. By Holger Rust* Excellent design with Terraforce in Spain, combined with impeccable construction techniques

I

t stands to reason that in communities where, due to circumstances, aesthetic values are not highly regarded, the demand for quality outcomes is not a priority. The emergence of free-loading material suppliers and unscrupulous contractors is thus encouraged, and the downhill trend is set in motion.

A question of ethics

CLASS LEADING DESIGN AND CONSTRUCTION

Large scale Terraforce retaining walls with stabilised backfill and professional installation provide a practical solution to severe erosion

22 IMIESA May 2024

In this scenario, the question of ethical values among individuals and corporate entities comes into play. Dr John C Maxwell, well known author of numerous business books, maintains that corporate ethical values are reflected in the values of their CEOs. However, ethical values, like moral values are not universally normative, i.e. cannot be regulated without risking abuse of such laws.

This means that other, self-regulating mechanisms must be employed.

At the Civulation Congress in 2014, Advocate Thuli Madonsela addressed the infrastructure engineering industry on the subject of corruption and ethics, highlighting seven points in the SAICE (South African Institution of Civil Engineering) Code of Ethics, namely: 1. Act with integrity and fairness.

2. Have regard for those that are affected by your professional activities.

3. Maintain and broaden competence and assist others to do so.

4. E xercise appropriate skill and judgement.

5. Avoid conflict of interest.

6. Treat people with dignity.

7. D on’t misrepresent your level of competence.

When applied as intended, these guidelines will have an uplifting effect on dealings in general.

However, as Groucho Marx cynically put it in one of

RETAINING WALL SYSTEMS his shows, “If you can fake it, you’ve got it made.”

The fake-brigade may be hiding in the background.

So, if ethical values and behaviour are difficult to regulate with legislation, what remains to be done to maintain acceptable levels of quality in the construction industry?

The gatekeepers The following are key quality gatekeepers: - Suppliers: they remain at the forefront of providing specifiers, clients, designers, and contractors with state-of-the-art information to ensure delivery of quality products/structures.

Terraforce and its licensed manufacturers have done so for almost 45 years in the form of design and installation guidelines, design software, laboratory testing, evaluation reports and numerous newsletters/case studies.

- Statutory bodies and professional institutes (such as SAICE): they publish and promote minimum standards and Codes of Practice.

These include: • SANS 508: 2006, Concrete Retaining Blocks (or as amended), being a material specification, based in part on the original Terraforce block specification of 1991.

• SANS 207:2011, The design and construction of reinforced soils and fills (or as amended), being a per formance specification, also influenced by the Terraforce manual of 1991.

• SANS 1044, covering general issues related to safety on building sites, during construction and after.

• Various booklets published by the Concrete Manufacturers Association (CMA) pertaining to the design and construction of segmental block retaining walls.

- Communication campaigns: raising awareness among consumers of the true cost of taking shortcuts and habitually choosing the cheapest offer on the table is crucial. Selecting experienced contractors or Terraforce recommended installers is always a safe idea. Terraforce, the CMA and various construction publications have regularly raised awareness to good effect. However, extraordinary weather outbursts, as they occur at irregular intervals, can put a damper on the good results that were achieved.

Misconceptions that need clarification This brings us to the need of publishing this

Inadequate mass, no drainage and possibly an undermined foundation

advisory, but not before shining the spotlight on some misconceptions that can lead to misrepresentations.

The aforementioned material specification, SANS 508: 2006, stipulates a much higher standard for concrete mix designs and dimensional tolerances for retaining blocks than is required for building blocks. This is often not understood by the customers of such products or in isolated cases not even by the producers of such blocks.

Furthermore, the design of load bearing retaining structures as per SANS 207:2011, BS 8006-1 and ASTM D6916-18 must be undertaken by qualified professional engineers.

Some engineers are not routinely dealing with these complex design mechanisms and prefer to task other engineers with more experience in this field.

Software

EXAMPLES OF POOR PRACTICE

No drainage, no supervision, no reinforced concrete infill, as specified

Free design tools such as the Terraforce Table Creator can at best be used to design low domestic retaining walls or they can be used as an estimating tool for tender purposes. In turn, free branded software such as Terraforce Maxiwall is a full design tool that can also be used for estimating purposes and further for difficult calculations in respect of global stability and complex soils, according to international standards. It stands to reason that designs undertaken with free design tools are “belts and braces” designs to minimise the risks involved.

Engineers with years of experience in rational design will produce more cost-effective designs that have the same stability characteristics.

If, and when failures do occur, it is mostly due to poor design, sloppy installation/supervision, as well as inadequate stormwater/subsoil water management.

areas add a responsibility, namely to accumulate and convey the excess run-off to the nearest municipal stormwater system at his own expense and over neighbouring property if necessary. The owner of neighbouring land must allow access for installation of such a conveyance route. The designer of such a system should be suitably qualified and must consider the entire potential flood volume of the properties in question and must also stipulate a regular maintenance programme.

A few failure reports that we have seen in recent years unfortunately suggest that some forensic investigators, tasked with assessing such failures, are not fully aware of the stormwater challenges and issues involved.

Stormwater attenuation

In closing

SANS 10400: Part R stormwater disposal prescribes in essence: • A landowner is allowed to discharge natural, unconcentrated stormwater run-off onto the lower lying land.

• Upgrades in the form of buildings of impervious

It is probably fair to say that by following these guidelines, you will gain peace of mind and maintenance of value, that insurance providers will be happy to cover. *Founder and head of Terraforce

TERRAFORCE DESIGN GUIDE & BOOK OF IDEAS Scan the QR code to access the Terraforce Book of Ideas and the two-par t Terraforce Design Guide (Section 1: Gravity Retaining Walls, and Section 2: Reinforced Soil Retaining Structures.)

IMIESA May 2024

23

LEGAL

PRECCA updates emphasise third-party accountability South Africa is continuously suffering from the effects of corruption and drainage of resources, some of which were highlighted in the State Capture saga. Optimistically, significant changes have occurred in the public and private spheres to ensure that the industrial-scale corruption perpetrated does not continue to repeat itself.

By Lionel Van Tonder and Danniel Kruger

O

ne such change is the recent signing of the Judicial Matters Amendment Bill into law

by President Cyril Ramaphosa on 3rd April 2024. Critically, the Bill expands culpability for corruption under Section 34 A of the Prevention and Combating of Corrupt Activities Act (PRECCA).

Section 34 of PRECCA makes it obligatory for anyone in a public or private company who learns of corruption or fraud to report it to the South African Police Ser vices if the value of the incident loss is over R100,000.

Now, as of 3 rd April, if authorities in private or public companies fail to stop “associates” from engaging in corruption, they themselves will be liable.

The inclusion of third-party contractors in the widened definition of the PRECCA is informative. Third parties have been at the heart of corruption in South Africa

Lionel Van Tonder, Director, Webber Wentzel

24 IMIESA May 2024

before, during, and after the State Capture era due to their ability to abuse public and private procurement processes. Instead of corrupt par ties dealing directly with their facilities, third parties are regularly used to create a layer of bureaucracy between the parties committing the fraud, so it’s harder to identify, with third parties compensated for their efforts.

It’s a timely and needed change. Section 34 A gives public and private companies the oppor tunity to avoid sanctions if they can show that they have put “reasonable measures” in place to prevent corruption in their organisation. However, “reasonable measures” are not yet defined in South

African law, which leaves a lingering question: What can reporting organisations do to show they have done all they can to prevent corruption by a member of staff or an associated third party?

A good star ting point is to consider the United Kingdom’s Briber y Act because Section 34 A of PRECCA is based on this. The UK Briber y Act refers to six principles that are used to judge whether an organisation has “done enough” to stop corruption from within and by parties they work with externally. These principles are propor tionality, top-level commitment, risk assessment, due diligence, communication, monitoring and review.

At present, these principles are being applied as guidance for what “enough” looks like in a South African context.

Over time, the cour ts will provide clarity on the minimum requirements as matters enter litigation. Until that

Danniel Kruger, Senior Forensic Manager, Webber Wentzel

LEGAL

happens, organisations and their leaders must proactively act to set up and leverage systems that can identify problematic employees, patterns, and third-par ty contractors in advance.

Prevention is better than cure We’ve found that companies and public organisations are far more reactive than proactive in stopping corruption at the source.

Leaders of organisations can fall into the trap of “fighting the last war” since the most up-todate view of corruption they have is the last corrupt transaction perpetrated before the instigators were caught.

Reactively, whistleblowers generally provided three-quarters of the intelligence

used to catch corrupt employees and third parties. The importance of whistleblowers is likely to stay the same. However, looking at it more from a proactive view, data analytics is providing a new front for companies to tackle corruption before it can take place.

The most proactive clients do more than just monitor data as it enters the system in realtime. They analyse and sift through current and historical data to identify previously missed patterns and red flags, such as invoices that are processed on weekends (fewer people means less oversight) and an employee taking no leave in three or four years. Stopping corruption at the source requires setting up the systems and parameters for continuous learning, testing,

proactive reporting, and filtering out false positives from acts of corruption and fraud.

Organisations that fail to address and report corruption promptly face potential legal and reputational risks. To mitigate these risks, creating a suppor tive environment that empowers employees to report fraud as they see it is strongly recommended. Furthermore, time spent vetting third parties is now of vital importance since the third parties a company uses are more likely to be pur veyors of corruption than the company itself.

While it is impossible to stop all corruption – criminals are ingenious in that way – it is the fiduciary responsibility of organisational leaders to do everything they can to meet the threshold of “enough” and more.

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• Regional Waste Studies • PPP Involvement in Waste Management • Alternative Technologies for Waste Diversion • Integrated Waste Management Plans • Closure/Rehabilitation Cost Provisions

T: +27 (0)21 982 6570 F: +27 (0)21 981 0868

www.jpce.co.za 60 Bracken Street, Protea Heights Brackenfell, South Africa, 7560

P O Box 931, Brackenfell, 7561

WASTE MANAGEMENT

LABORATORY SUPPORT IS CRUCIAL FOR GOOD WASTE MANAGEMENT Before waste may be disposed of to a landfill, it must be analysed by a South African National Accreditation System (SANAS) approved laborator y to understand its chemical and physical makeup. In managing its waste, industr y must follow the waste hierarchy principles of prevention, followed by reuse, recycling, recover y, and finally disposal.

I

n this respect, EnviroSer v Waste Management’s accredited laborator y analyses waste to reduce risk and minimise its impact on the environment. Having competent laborator y staff is an essential part of managing hazardous waste to achieve these objectives.

“Our experienced team at our ISO 17025:2017 SANAS accredited centralised laboratory at our Johannesburg head office knows and understands the chemical and physical properties of the waste they are assessing,” explains Mahmood Patel, EnviroServ’s National Laboratory Manager.

“Waste classification and assessment of waste helps with the evaluation of appropriate waste management strategies.”

Before disposal to landfill, landfill operators must first have suf ficient information about a particular waste as

this informs the landfill class at which the waste may be treated and disposed of.

Legislation In 2013, three sets of waste management regulations were promulgated under the National Environmental Management: Waste Act No. 59 of 2008. One of these, the National Norms and Standards for Disposal of Waste to Landfill, lists various prohibitions regarding types of waste that may not be disposed of to landfill. Certain waste types, including liquid waste and whole tyres, are prohibited from being landfilled, along with lamps, batteries and hazardous waste with calorific values above their disposal limits.

“In terms of the National Environmental Management: Waste Act 59 of 2008, a person

commits an offence if they contravene or fail to comply with regulations,” says Patel.

A person convicted of an offence is liable to a fine or to imprisonment.

Disposal plan EnviroSer v has a policy that no waste handling activity may be started unless a disposal plan for both non-hazardous and hazardous waste has been drawn up.

“By applying this principle, we assist our customers in responsible waste management, following all prevailing waste management legislation and avoiding environmental contamination or an undesired reaction when disposed of with other waste types,” adds Patel.

EnviroServ offers peace of mind through the provision of containment of hazardous waste, and issues clients with safe disposal certificates.

Mahmood Patel, EnviroServ’s National Laboratory Manager

26 IMIESA May 2024

PIPE SYSTEMS

PLASTIC PIPES MEET MODERN SEWER DEMANDS As communities globally grapple with the challenge of maintaining effective water and sewer networks, a critical solution emerges in the form of plastic pipes.

W

ater and sanitation infrastructure, alongside housing, are pressing priorities in South Africa today,” says Jan Venter, CEO of the Southern African Plastic Pipe Manufacturers Association (SAPPMA).

“Local and national governments therefore have a crucial role to play in uplifting communities by implementing ef fective sewer and waste management systems.

When installing pipelines for water and sewage systems, adherence to engineering and product standards is paramount to deliver optimal results that are both practical and cost-effective.”

Both PVC and HDPE plastic pipes offer a durable solution that surpasses traditional

materials like steel and concrete. Their suitability to labour-intensive construction techniques, coupled with minimal maintenance requirements, makes them an ideal choice for sewage systems of var ying complexities.

Sustainability Fur thermore, plastic pipes contribute to sustainability efforts by promoting a circular economy. Multi-layered PVC pipe systems allow for the reuse of post-consumer and in-house recycled material, aligning with environmental conser vation goals while maintaining the required durability and per formance standards.

“One of the key advantages of plastic pipes is their resistance to corrosion, a

Jan Venter, CEO of the Southern African Plastic Pipe Manufacturers Association (SAPPMA)

common issue faced by traditional sewer systems. Unlike steel and concrete pipes, plastic pipes remain structurally sound and water tight over extended periods, even in corrosive environments. This resilience ensures a longer ser vice life, reducing the need for frequent maintenance and costly repairs,” Venter explains.

In addition, the versatility of plastic pipes extends to trenchless technology, facilitating ef ficient rehabilitation and replacement of existing pipelines without the need for extensive excavation. Techniques such as pipe bursting, slip lining, and cured-in-place pipe offer practical solutions for upgrading aging infrastructure while minimising disruption to communities.

Quality assurance SAPPMA and its sister organisation, the Installation and Fabrication Plastics Pipe Association (IFPA) play pivotal roles in ensuring the quality and reliability of plastic pipe systems. Both these organisations ensure that their members adhere to rigorous quality standards through stringent product and process audits, thereby providing assurance to specifiers and endusers alike.

“Our commitment to quality and adherence to standards are integral to promoting the integrity of plastic pipe systems. To this end our stringent audits and cer tification processes not only distinguish our members in the industr y, but also offer peace of mind to clients and end-users,” Venter concludes.

For more information, please visit www.sappma.co.za

IMIESA May 2024

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WATER & WASTEWATER

TACKLING POLLUTION KEY TO WATER LETTUCE ERADICATION Spraying glyphosate-based herbicides (GBH) to control the spread of water lettuce in the Vaal River was suspended in early March 2024 due to public concern and debate around the efficacy, safety, and long-term impact of these chemicals.

T

here are potential unforeseen negative implications associated with chemical and biocontrol appr oaches,” comments Dr Anthony Mader, Senior Environmental Scientist, with a PhD in the interdisciplinary field of phytoremediation, at globally trusted infrastructure consulting company AECOM. Dr Mader points out that an additional important consideration when developing any integrated alien invasive plant species plan is to identify the contribution of the targeted alien invasive plant species to nutrient biogeochemical cycles. Plants can directly influence nutrient biogeochemistry by altering the turnover of nutrients through nutrient uptake dynamics and plant senescence and/or death (Austin and Zanne, 2015). For example, the sinking of senesced or dead plant matter (due to herbicide/biocontrol action) down the water column, and consequential decomposition and liberation of ad/absorbed nutrients, mediates the biogeochemical cycling of nutrients.

“This phenomenon can result in the acute/ chronic reintroduction of nutrients within the

28 IMIESA May 2024

Vaal River system, thereby increasing the concentration and bioavailability of nutrients conducive to the proliferation of water lettuce, water hyacinth, and harmful algal blooms (HAB),” notes Dr Mader.

Hence, the main areas of concern are: • Acute and chronic release of elevated levels of nutrients into the Vaal River, and • Ecotoxicity and the fate and transport of GBH in the environment (which may negatively impact the growth and survival of non-target, indigenous plant species).

The discharge of sewage and agricultural runoff, containing high levels of bioavailable forms of nitrogen (ammonium, nitrates, and nitrites), phosphorous (phosphates), and trace elements, as well as dissolved and suspended organic matter, results in eutrophication. This can change the biological and hydrogeochemical characteristics of the Vaal River, creating conditions conducive to the proliferation of alien invasive plant species and/or HABs. In February 2024, Rand Water developed an integrated alien invasive plant species

management plan that combined mechanical plant removal, chemical application, and the release of biocontrol agents [water lettuce weevils (Neohydronomus affinis)] to control the propagation and migration of water lettuce within the river system.

Tshuxekani Maluleke, a Senior Environmental Scientist, with an MSc in the field of biocontrol, comments: “Based on the invasion biology of water lettuce, the efficacy of biocontrol measures depends on spatial and temporal factors whereby biocontrol agents must be released prior to the reproductive stages of the plant’s lifecycle.”

An emergency General Authorisation (GA) was issued by the Depar tment of Water and Sanitation to Rand Water to implement measures to control the spread of water lettuce.

However, the use of a GBH was challenged by various communities, academics, and legal experts based on: • The ecotoxicity of glyphosate, especially when sprayed directly into a water resource, and • The legal standing of herbicide spraying, which has been stated as allegedly being

WATER & WASTEWATER Dr Anthony Mader, Senior Environmental Scientist at AECOM Tshuxekani Maluleke, Senior Environmental Scientist at AECOM Elisabeth Nortje, Associate Director – Environment, Africa at AECOM

an unlawful activity in terms of the National Water Act (No. 36 of 1998).

Limited human-based studies have been conducted on glyphosate toxicity, with conflicting results. Various agencies (for example, the US EPA) have classified glyphosate as minimally or not toxic to humans, based on numerous factors.

“However, constituents such as surfactants – for example, isopropylamine – are combined with glyphosate to increase its bioavailability and phytotoxicity. These constituents increase the ecotoxicity of glyphosate,” says Dr Mader.

Transgenerational toxicity He points to a recent study demonstrating that glyphosate may have a transgenerational toxicity. “Although the study was conducted on rodents, the findings highlight the need to apply the precautionary principle when spraying GBH directly into a water body, that is ultimately used for drinking water, and that cannot be effectively removed from traditional water treatment works, due to the physicochemical properties of glyphosate,” argues Dr Mader.

Moreover, the presence of water lettuce is indicative of an underlying problem, namely the acute and chronic discharge of contaminants into the Vaal River and its tributaries from both point and non-point sources of pollution.

Controlling the symptom (water lettuce) does not address the source of pollution – ultimately maintaining the water lettuce/water hyacinth/ algal bloom eutrophication paradox.

“Moreover, the physical, chemical, and/or biocontrol of water lettuce [a species that has been used as a tool for phytoremediation (rhizofiltration and phytoextraction) due to its ability to accumulate elevated levels of nutrients that contribute to eutrophication], reduces competition for nutrients – creating conditions conducive to the proliferation of cyanobacteria (also known as bluegreen algae) and thus potential HAB,” Dr Mader continues.

“This highlights our need to shift our perspective on how we address environmental challenges, focusing on identifying and remediating contaminants prior to their release into the environment,” comments Dr Mader.

In alignment with its Sustainable Legacies strategy, AECOM is committed to creating sustainable solutions to complex challenges and enhancing the provision of vital ecosystem services, adds Elisabeth Nortje, Associate Director – Environment, Africa.

The Small and Medium Enterprises (SMEs), that form par t of AECOM’s Enterprise Capabilities (EC) Sustainability and Environmental portfolios, provide various

nature-based solutions to address complex environmental and socioeconomic challenges.

Constructed wetlands A key service offered is the design and implementation of constructed wetlands (CWs), which are engineered biological and hydrogeochemical systems with controllable functional (integrating phyto- and bioremediation technologies) and operational (for example, hydrological regime) parameters to optimise the remediation of a range of inorganic and organic contaminants present in wastewater (Mader et al., 2022).

Hybrid CWs can be designed to address and mitigate point and non-point source pollution events, reducing the release of contaminants required for water lettuce and cyanobacteria to proliferate. Simultaneously, this approach enhances the provision of ecosystem services amidst climate change to promote sustainable development.

Additional EC SME components from AECOM include, but are not limited to, wetland and riparian zone rehabilitation, ecosystem services assessments, regenerative ecology, flood management, and carbon sequestration, incorporating sustainability frameworks into the design and effective delivery of sustainable, resilient, and equitable naturebased solutions.

REFERENCES Austin, A.T. and Zanne, A.E., 2015. Whether in life or in death: fresh perspectives on how plants affect biogeochemical cycling. Journal of Ecology, 103(6), pp.1367-1371.

Bai, S. H. & Ogbourne, S. M. Glyphosate: environmental contamination, toxicity and potential risks to human health via food contamination. Environmental Science and Pollution Research. 23, 18988–19001, https://doi.org/10.1007/ s11356-016-7425-3 (2016).

Blake, R. and Pallett, K., 2018. The environmental fate and ecotoxicity of glyphosate. Outlooks on Pest Management, 29(6), pp.266-269. de Araujo, J. S., Delgado, I. F. & Paumgartten, F. J. Glyphosate and adverse pregnancy outcomes, a systematic review of observational studies. BMC Public Health 16, 472, https://doi.org/10.1186/s12889-016-3153-3 (2016).

European Food Safety Authority (EFSA), 2015. Conclusion on the peer review of the pesticide risk assessment of the active substance glyphosate. EFSA Journal, 13(11), p.4302.

Mader, A.E., Holtman, G.A. and Welz, P.J., 2022. Treatment wetlands and phyto-technologies for remediation of winery effluent: Challenges and opportunities. Science of the Total Environment, 807, p.150544.

Relyea RA. The lethal impacts of Roundup and predatory stress on six species of North American tadpoles.

Archives of Environmental Contamination and Toxicology.

2005;48:351Y357 US Environmental Protection Agency, Washington DC. Reregistration Eligibility Decision (RED): Glyphosate.

EAP-738-R-93-014, September 1993.

IMIESA May 2024

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WATER & WASTEWATER

GETTING VALUE FROM SMART WATER TECHNOLOGIES Barcelona is a unique city, blending old monuments and cathedrals with a ver y modern and bustling metropolis. But it has a few things in common with South Africa's towns and metros, notably a semi-arid climate with limited access to water. As water stresses increased, Barcelona's authorities needed to make a plan – and they decided to use smar t water technologies. The results have been incredible. By Chetan Mistry

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imilar oppor tunities exist in South Africa where water providers are struggling with gr owing demand, ageing infrastructure, and shifting weather patterns. Exper ts warn about water shor tages as several major cities and towns have already implemented water restrictions. Meanwhile, major water infrastructure is breaking down in large metros such as Johannesburg and eThekwini, buckling under the dual strains of rapid population growth and underinvestment in maintenance.

Though the situation looks increasingly dire, water utilities have a big oppor tunity. Innovation in engineering and digitisation has honed a range of smar t water solutions that can help improve existing water systems without massive replacements, giving sites time and space to scope their future improvements with the help of data-driven insights

to improve efficiency, forecasting, and demand prediction.

Smar t water solutions have developed extraordinarily in the past twenty years.

They can deliver specific point solutions, large overhauls, or star t collecting and analysing rich data for planning. One of the biggest advantages today is that you can tackle a specific problem with a smar t solution, then use that investment to tackle the next problem.

You can scale effor t while keeping costs under control.

Smar t water technologies ar e fundamentally data driven. They collect and leverage water per for mance data to improve results through better management and visibility.

Examples include smar t sensors that collect various data points, data analytics for planning and ef ficiency, predictive maintenance, integration of dif ferent infrastructures for improved per for mance, and comprehensive

Chetan Mistry, Strategy and Marketing Manager at Xylem Africa

30 IMIESA May 2024

WATER & WASTEWATER

real-time visibility through interactive dashboards (accessible anywhere via the cloud and an internet connection).

The ROI of smart water These innovations have a lot to of fer, and they are cost-effective. But, like all infrastructure solutions, there are still investment concerns. What is the value, the return on investment (ROI), of a smart water solution? Utilities can jump into smart water systems only to get less return than expected. How can utilities invest in the right smar t water technologies and start to get that momentum they can build on and modernise their sites?

The two crucial steps to realising healthy ROI from smar t water are embracing a digital modernisation strategy and focusing on value beyond cost. Digital modernisation is neither a mere rip-and-replace strategy nor as simple as installing and linking a few sensors to software. To get good results, the vision must be more specific.

Water sites already use technologies; they have sensors and software. Smar t

water systems take things to the next level because they enhance what you already have and introduce new methods and insights. This means you rely only on a technical or cost mindset. You should choose smar t solutions that work for a site's strengths and enhance the site's requirements. Star t with a plan, a vision, for the site, then look for specific oppor tunities to apply smar t water solutions.

For example, a site might already generate useful data, but the overall management tools are isolated. Collecting information requires considerable time before one can predict consumption levels or maintenance demands. In this case, water managers can unify water operations through cloud platform dashboards that securely consume the data, analyse results, and deliver single-truth insights to authorised personnel wherever they are—on-site, at the office, or even on the road.

Modernisation with a plan delivers results A municipality could recoup costs by

reducing non-revenue water. To do so, they can use smar t flow systems to measure water allocation and consumption, identifying where there are losses. They can employ smar t leak detection to pinpoint problem areas without shutting down the water pipelines for inspections.

Ever y site has unique needs and priorities.

Smar t water succeeds when there is a mindset for modernisation and a strategy to suppor t that vision. These needn't be massive projects—there are many lowhanging fruits that water utilities can exploit to see quick gains.

With the right planning and par tners, smar t water delivers great returns on investment. Barcelona reduced overall water usage by a massive 25% while still finding more revenue through optimisation, cost savings, and better ser vice to customers. All of this was accomplished by adding smar t technologies to the city's sprawling (and often antiquated) water systems. Imagine what smar t water solutions can do for South Africa's struggling water infrastructure.

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WATER STORAGE

Water storage backup for a manufacturing client

WATER STORAGE AND ENERGY a two-pronged approach

South Africa, as a developing nation, is experiencing increasing constraints on its water infrastructure, exacerbated by droughts and grid pressures that lead to loadshedding. IMIESA speaks to Chester Foster, MD of SBS Tanks (SBS), about the group strategy, market penetration, research and development (R&D), plus the growth of SBS Energy as a diversified business offering.

An elevated tank designed and commissioned for the municipal market

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perating locally and globally for close to three decades, SBS is a leader in innovative water security solutions, headquartered in KwaZulu-Natal, with offices in Southern Africa, East Africa and the USA. Direct sales to the market are supported by a dealer and distributor network in the USA, Malaysia, Myanmar, and Mauritius, as well as in other African regions.

32 IMIESA May 2024

“My focus as MD is on growing our South African footprint, where we already have an extensive presence in all four of our main segments – namely fire, commercial, municipal, and mining,” Foster explains.

“There’s a clear decentralisation trend emerging when it comes to water demand management and security as water interruptions due to overloaded and ageing infrastructure becoming increasingly common in South Africa, negatively affecting all

industries and households. This has significantly increased the demand for on-site storage – whether for rainwater harvesting, potable supply or for water-intensive manufacturing industries like mining and FMCG,” he continues.

“In response, we can provide a rapid solution to supplement existing municipal concrete reservoirs, keep production processes ongoing, or to install tanks where communities don’t currently have access to water deliver y, particularly in rural areas. The property market is also a key growth area because HVAC systems and ablution facilities installed on largescale developments – like shopping centres, office blocks or hospitals – need large volumes of water to operate.

“If there’s no mains supply available, then that’s a major health and safety concern in many cases – and a no go for trading. At present we’re installing around 200 000 litres of storage for a commercial building in Durban to minimise the impact of this scenario and ensure the toilets work.”

Compared to the longer timeframes required for concrete reservoirs, SBS’s tanks can be constructed and commissioned in a matter of days or weeks – depending on the tank size and installation complexity – saving on time and construction costs. Installation requirements typically entail a simple cast in-situ reinforced ring beam for the tank foundation, with the modular frame sections designed for ease of transportation irrespective of the terrain.

SBS’s galvalume – a metal mix of 55% aluminium and 45% zinc – modular tank series is manufactured in South Africa for domestic and export markets in accordance with ISO 9001:2015 and ISO 45001:2018 quality standards. Over 500 tank sizes are available, with capacities ranging from around 7 000 litres to 4,2 ML (the latter measuring around 24 m in diameter and 9 m in height).

WATER STORAGE Liners The liner systems employed are internationally certified for applications that include potable water, saltwater for desalination plants, various chemicals, and effluent water and come with a 10-year non-leak warranty. The tanks themselves – which can be powder-coated in a range of colours – have a 60+ year life expectancy, with the liners typically lasting 20 years before any maintenance is needed.

SBS Tanks has a well-established presence in the mining segment

R&D trends SBS’s R&D team continue to innovate in terms of their standard and custom solutions to cater for diverse needs. These include, for example, the incorporation of an internal floating roof system for applications that include landfill leachate storage.

In addition to the standard range, product lines include the Econo water tank (from 7 KL to 253 KL) for smaller scale uses like rainwater harvesting; and the Cyclonic series – capable of withstanding wind speeds up to 240 kph – for regions that experience severe meteorological events, like hurricanes. The latter have been supplied into neighbouring regions that include Mozambique, as well as internationally.

In turn, the ES (Engineered Solution) range caters for the firefighting segment, designed to fit tight footprint requirements. At times, that translates into thinner and taller tank designs.

Councils are also increasingly requiring complexes and buildings to install backup hydrant water tanks in the event of a loadshedding and/or water shedding event.

Elevated and seismic resistant tanks The most recent development is SBS’s Elevated tank range, with capacities of up to 400 KL and a maximum height of 15 m to boost water pressure delivery. These incorporate SBS’s classic round tank design, mounted on a steel deck. To date some ten units have been installed, with strong uptake from industry.

“Another key development is the rollout of our seismic tank range following some three A tank storage solution supplied for a desalination project at Kenton-on-Sea in the Eastern Cape

years of research completed in conjunction with the University of Cape Town and Stellenbosch University. The outcome is a unique seismic calculator that determines the sector and regional requirements for each custom build.

These tanks are designed to withstand naturally occurring or mining related seismic activity,” Foster explains.

the commissioning of two 3,3 ML tanks in the Eastern Cape that will support potable water supply for some 3 200 community members who are predominately seasonal pickers in the local agricultural industry. Powder coated in a cream finish, they each measure 22 m in diameter and 9 m in height.

SBS Energy Fit-for-purpose Every tank supplied across SBS’s comprehensive range has a greater or lesser degree of customisation, with the group’s in-house engineering team perfecting each fit-for-purpose solution, working where applicable with the client’s engineers.

A current example is the design of four 3 ML tanks for a desalination project in Mozambique for a petrochemical client – two for seawater and the balance for treated potable water storage.

“Areas like rainwater harvesting are still in the early stages of adoption, but it’s a logical and increasingly environmental imperative, especially with the progressive increase in municipal water tariffs. Some of the more significant projects we’ve worked on in this area include a series of schools within the eThekwini region, with further initiatives ongoing. Aside from a municipal water supply backup, these rainwater tanks have achieved notable savings in terms of toilet flushing,” says Foster.

Overall, the municipal market has always been one of SBS’s key sectors with a well-established pipeline of installed projects. Recent ones include

Alongside its tank offering is the addition of SBS Energy, initially for the solar PV rooftop commercial and industrial market, but now with allied penetration in terms of groundmounted installations for sectors that include agriculture. For the latter, these are either standalone or hybrid genset/PV/grid power solutions to run operations and irrigation, as well as pumps employed for dam, groundwater or river abstraction.

The starting point for businesses is power security; grid electricity savings in the medium term; and a greener approach longer-term, says Foster. However, SBS does see a shift towards applying a tank and energy approach going forward across all industries, including clinics, hospitals, and schools, as well as communitybased projects that don’t have grid access.

Depending on the need, this could integrate with modular water and/or wastewater process units supplied by the general market.

Closing remarks “Unless it’s a lifesaving intervention, we can weather power outages for a short while, and it can be countered with gensets and renewable energies like solar. But that’s definitely not the case for water in terms of its socioeconomic impact. Cape Town came close to ‘ Day Zero’ (when the taps could have shut off), and Gqeberha was a near second from a drought perspective,” adds Foster.

“As underscored by the 2024 UN World Water Day slogan ‘ Water for Peace’ we have an increasingly finite resource that must be equitably shared to avoid conflicts. Having it in a tank – for contingencies or as part of a managed system – makes practical, social and business sense,” Foster concludes.

IMIESA May 2024

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MUNICIPAL FOCUS – NELSON MANDELA BAY

PUBLIC-PRIVATE PARTNERSHIPS ARE KEY TO ADDRESSING SA’S WATER CHALLENGES Extended droughts, ageing infrastructure, and non-revenue water (NRW) losses – combined with intensive urbanisation and population growth – are placing increasing strain on South Africa’s water resources, requiring a collaborative response from both the public and private sectors.

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his was the driving force for the establishment of the Strategic Water Partners Network South Africa (SWPN) – launched in 2011 at COP17 in Durban. A multi-stakeholder private and public sector initiative, SWPN members are working collectively to close an anticipated 17% gap between water supply and demand by the year 2030. This is an initiative executed in conjunction with the 2030 Water Resources Group, a publicprivate-civil society water partnership on a global scale hosted by the World Bank Group, to accelerate Sustainable Development Goal (SDG) outcomes.

Locally, South Africa’s National Water and Sanitation Master Plan (NWSMP) and the National Water Resources Strategy (NWRS) formally identifies the SWPN – which is hosted by the NEPAD Business Foundation – as a key enabling platform. To date, joint efforts with the Department of Water and Sanitation

have included the introduction of the No Drop water use efficiency rating scorecard aimed at municipalities to encourage performance excellence through a rewards and penalties system.

Milestone SWPN projects within the municipal space include the signing of a Memorandum of Understanding (MoU) with Polokwane Local Municipality in 2018, in conjunction with two of its key private sector partners, Anglo American and the South African Breweries (SAB), with a focus on addressing NRW issues in the city.

Phase I included a detailed commercial and real water loss investigation, plus the development of a strategy and business plan.

In turn, Phase II focused on interventions that include the installation of bulk meters, pressure reducing valve (PRV) service and maintenance, top consumer audits and monitoring, as well as reservoir level and bulk meter monitoring. High level findings showed a marked improvement in NRW reduction.

Nelson Mandela Bay Water Partnership Based on the traction gained in Polokwane, one of SWPN’s next ports of call was Nelson Mandela Bay Metropolitan Municipality (NMBM) – given its spate of prolonged droughts. Engagements took place with some local companies, as well as NMBM, National Treasur y, and the City Suppor t Programme. Subsequently, this led to the signing of an MoU between SWPN and NMBM in July 2022. SAB concluded a financing agreement with SWPN and contributed R2,5 million in funding to kickstart the programme.

Currently, NMBM has a total potable water supply capacity of around 281 357 m3/day.

However, daily supply volumes are typically only 81 800 m3/day, while the NRW losses are concerning, at around 55,4%. Real losses amount to some 29%, while the water tariff collection rate averages around 40%.

Proposed activities to achieve the programme’s longer-term objectives include:

Before and after perspectives of a bulk meter installation upgrade within NMBM

34 IMIESA May 2024

• Water conservation and water demand management (WCWDM): this encompasses water conservation in general, in parallel with interventions such as fixing leaks at public schools, government buildings, plus reducing the current leak repair backlog.

• Water infrastructure improvement: the project will assist with improvement of water infrastructure by repairing or replacing aging water meters, installing new pumps and PRVs. Fur ther phases could include upgrading pipelines and water treatment plants.

MUNICIPAL FOCUS – NELSON MANDELA BAY Construction works in progress for the establishment of a metering chamber within the Rowallan Park Extension zone

• C ommunications campaign: of key impor tance is the promotion of public education and awareness. This incorporates information on how to reduce water usage in the home, at school, and in the workplace, as well as promoting greywater reuse and rainwater harvesting.

• Water investments: establishing the groundwork for public and private investments in water infrastructure in the city is the overriding factor. Essentially, this increases economic oppor tunities through improved access to water for businesses and industries. It also enhances environmental sustainability through proactive conservation, thereby improving the quality of life for all residents through reliable access to safe and clean water.

Starting point In May 2023, a Call for Proposals was issued

by NMBM for SWPN bids to suppor t the implementation of five new zonal bulk meter installations in accordance with NMBM’s NRW 10-year Business Plan.

The selected installations targeted two Greater Managed/Metered Area (GMA) supply zones as par t of the construction works, namely the Bloemendal Reser voir (23 Mℓ capacity) and Rosedale Reservoir (9 Mℓ capacity) supply zones. In turn three District Metered Ar eas (DMAs) wer e addressed as par t of the bulk water meter installations, namely Lee A new bulk meter installed to provide accurate flow data

Samuels Drive, Rowallan Park Extension and McNaughton Township South.

The Lee Samuels Drive DMA zone is supplied by the Bloemendal Reservoir via a 160 mm uPVC offtake from the bulk 500 mm AC pipeline; while the Rowallan Park Extension zone is supplied by the Greenbushes Reservoir (25 Mℓ capacity), which receives water from the Kromme bulk water supply scheme (Churchill and Impofu dams) via the Seaview pump station. Rowallan Park Extension is supplied through a 110 mm Ø uPVC offtake from the 375 mm Ø outlet pipe of Greenbushes Reser voir into the zone.

In turn, McNaughton Township South is supplied by Rosedale Reservoir.

These DMAs, along with the two GMAs identified, required the installation of bulk meters so that NMBM’s technical team could measure the day and night-zonal time flow rates, identify leaks in the system, and ultimately ef fect the necessary repairs.

The completed McNaughton Township South bulk metering installation

The McNaughton Township South metering chamber nearing completion

In alignment with the NEPAD Business Foundation’s policies and procedures, the contract for an implementing agent (consulting engineer) was awarded to Engineering Advice & Ser vices. Subsequently, five SMME subcontractors were appointed, and the works were completed towards the end of 2023.

An ensuing performance analysis across the newly installed bulk meter installations has shown an NRW/apparent losses reduction of around 3 Mℓ/day. Each bulk meter is now also installed with a data logger that transmits information in real-time to NMBM’s SCADA system. This will prove invaluable in verifying flow characteristics and pressures, as well as technical and non-technical losses.

Overall, the project has demonstrated the potential impact of public-private collaboration in tackling water challenges. However, a far more comprehensive rollout of bulk meters and continued cooperation between various stakeholders will be essential to bring NRW losses within acceptable norms and ensure NMBM's future water security.

IMIESA May 2024

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ENVIRONMENTAL ENGINEERING A beach bag wall constructed as an erosion control measure along a section of Cape Town’s West Coast

GABIONS ENHANCE THE FINAL GREEN DESIGN AND PROTECT Among the key benefits of gabion systems are the ease of construction, the sustainable use of in-situ materials, as well as the opportunity to combine labour-intensive (LIC) and mechanised approaches. IMIESA speaks to Louis Chyene, managing director of Gabion Baskets about evolving applications and techniques.

S

ince gabions are environmentally engineered structures, their flush front face finishes should ideally be constructed so that they blend in.

That requires specific training in terms of how the overall infill rock and/or composite elements – which could include spoil material, depending on the application and hydrological factors – are placed within the galvanised double-twisted hexagonal steel wire or welded mesh frames that comprise each gabion unit to achieve the ultimate aesthetic result,” Cheyne explains.

For freestanding interior or exterior walls, or for building wall cladding, this typically means using welded mesh for exact flat finishes – a standard requirement for architectural works. In most cases, a “handpicked” material is selected and packed to create the desired effect. A case in point is a recent Gabion Baskets order for an approximately 300 mm wide welded mesh privacy wall within an upmarket residential estate in Lanseria, Gauteng.

Here an attractive slate-type material has been employed for the facing, while the internal core is composed of a 19 mm concrete chip fill.

Within the civils sector – road or river embankments being prime examples – that level of precision finish is not the ultimate priority, but it always comes with practical aesthetics in mind in terms of rock colour selection. This can be combined with the option of polyethylene wire coatings (the latter specified for more corrosive environments) in various colour options.

As Cheyne points out, labour is always required, like positioning, basket lacing and packing.

That’s especially important for community-based

36 IMIESA May 2024

projects, but when businesses need it “done yesterday”, civils projects can be significantly accelerated by using plant like backhoes and excavators to complete the bulk of the basket infill. This value engineering approach is further enhanced by the degree of batter selected. When optimised, it can reduce the necessary wall width – particularly for mass gravity walls – saving on rock and gabion wire materials.

“Rock material selection is especially important for riverine gabion structures to counter scouring. In this case, using unsuitable spoil materials like clay brick rubble is counterproductive as it will rapidly dissolve over time. However, spoil can be used to a greater or lesser degree in land-based mass gravity retaining wall structures. In all cases, the incorporation of geotextiles is essential for fines loss mitigation, as well as to achieve the controlled

Wall section design constructed with FiberRock® geosynthetic sand containers

degree of permeability from the rock fill interlock.

This typically provides for around a 35% void factor with a pure rock-fill composition,” Cheyne explains.

Health and safety “As with all gabion structures, adherence to strict health and safety norms in accordance with construction industry regulations is an essential requirement. Mass gravity retaining walls above 1,2 m in height must be designed and signed off by a professional engineer specialising in environmentally engineered structures. The design must ensure that there is no risk of the wall sliding or overturning,” says Cheyne. “Factoring in drainage is essential so that structures are engineered to withstand hydraulic pressure from soils and other loads behind and above them.”

Mass gravity wall project One of Gabion Baskets’ current projects entails the provision of design recommendations, gabion and rock in-fill material supply as well as project support services for a new 4 m high mass gravity retaining wall at Scaw Metals’ facility in Germiston, Gauteng.

ENVIRONMENTAL ENGINEERING

Before and after perspectives of a gabion wall constructed on the Zambezi River to protect the embankment

The section being remediated borders an electrical substation where the general area has become heavily eroded due to stormwater runoff and underlying poor subsoil conditions. This has subsequently been reinstated with G5-type material in preparation for the wall foundation and ensuing gabion works. The new wall will stabilise the current eroded embankment, which supports a pipeline and is bordered by a paved road above.

there, the client could then better visualise the final works, as well as their requirement for the incorporation of an upgraded gravel access road within the remediated zone.”

For the Scaw Metals project, the construction team has adopted the advantages of an LIC and mechanised approach to fast-track gabion fill rates by up to 20 m3 daily. (A single trained installer typically takes a day to pack 1 m3 by hand.)

Benefits of animation

River and coastal protection

“Increasingly our design recommendation services incorporate 3D animation renditions that transform ‘old fashioned’ 2D drawings into a very realistic perspective of what the final structure will look like. That then assists the client in deciding on the best rockfill colour match for their requirements, as well as the final optimum design approach,” says Cheyne.

“This was the case for the Scaw Metals site, with the software allowing us to superimpose the technical wall specifications over the animated rendition to create a 2D/3D hybrid model. From

Recently, Gabion Baskets’ well-established presence in the general flood, riverfront and beach erosion protection fields has been further enhanced by the conclusion of a distributor agreement with specialist manufacturer, Fibertex.

This includes the supply of the latter’s FiberRock® geosynthetic sandbags, which complement Gabion Baskets’ in-house flood barrier systems.

The latter are composed of a welded mesh steel gabion cellular frame lined with a durable geotextile that can be rapidly filled using on-site plant with any available material.

3D animation forms part of Gabion Baskets design services. The live view shows the position for a new 4 m high mass gravity retaining wall, while the 3D rendition provides an artist’s impression of how the final structure will look

Cheyne says demand is growing for beach sandbag installations in South Africa to counter wave erosion, as well as in neighbouring regions like Mozambique to protect properties and related infrastructure from rough seas and cyclone-related damage. At times these installations incorporate gabion elements for added structural stability, but these sandbags are designed to work optimally on their own and have an anticipated useable lifespan of more than 50 years.

One current proposal in Mozambique entails the stabilisation of an approximately 15 m high sand dune embankment utilising these geosynthetic sand containers.

“Erosion due to climate change, rising sea levels and land-use is an escalating concern that must be increasingly countered by proactive engineered interventions in various forms,” says Cheyne. “Foremost it’s an environmental issue but allied to that are the downstream impacts on enterprise and communities unless disaster contingencies are effectively well planned to mitigate immediate and future extreme weather events.”

Across South Africa and Southern Africa, a core part of Gabion Baskets’ multifaceted design recommendation and supply solutions are in the river protection space. Outside South Africa, various orders have been completed or are ongoing along the Zambezi River – particularly in Zambia.

A recent enquiry includes river frontage protection along an approximately 100 m long section for a mass gravity gabion wall with an approximate height of 3 to 4 m in Livingstone, Zambia, for a commercial client.

Overall, the demand for gabion systems keeps growing as a green solution. “It’s clear that the flexibility of gabion and allied environmentally engineered products have universal application and appeal across a broad building and civils spectrum, where their distinctive construction characteristics are among the most carbon neutral. We keep exploring the possibilities,” Cheyne concludes.

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RENEWABLE ENERGY & ELECTRIFICATION

A GREEN LIGHT FOR LICHTENBURG AND ITS COMMUNITY Wilson Bayly Holmes-Ovcon (WBHO) Construction, together with its joint venture par tner, the Sola Group, has completed the construction of the Merak 2 and 3 PV development.

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ne of Africa’s largest renewable energy projects under a Private Power Purchase Agreement, the installation covers approximately 4 km2 and will deliver power through a wheeling agreement to Tronox, a key player in the mining and minerals sector. The Merak 2 and 3 solar plants are situated near Lichtenburg in South Africa’s North West province.

The Merak 3 plant achieved commercial operation in March 2024 and Merak 2 in April 2024. This comes after a construction period that started in September 2022. WBHO is the majority partner for the design, procurement, construction, installation, connection and commissioning of the respective 130 MW and 126 MW solar PV plant and grid works.

Apart from contributing to renewable energy in South Africa, the project is especially meaningful as a pioneering example of how involving rural communities can foster shared growth and betterment.

“On arriving in the area, you could immediately notice the intense levels of need,”

says Shabier Ismail, a director in WBHO's Projects Division.

The area still experiences the impact of the severe social unrest in Lichtenburg and Coligny in April 2017. And violent protests are not uncommon today in the area.

“You meet the station commander at the police station. You meet the community leaders. You meet a councillor, and they all tell you the unemployment in the ward is 90%, and then you realise you are not just here to build a project, you are here to make a difference,” Ismail continues.

In this respect, the project created over 800 local jobs. Dozens of sub-contractors were also hired from the surrounding area, including Bakerville, Grasfontein and Carlisonia.

Adding back to those in need The WBHO Sola joint venture, in partnership with the employer, also set aside a ringfenced budget for community initiatives during the construction period. This enabled various positive social outcomes that include the establishment of vegetable gardens; the repair

of streetlights to increase night-time safety; the provision of 1 000 school bags, stationary, sanitary packages, and sports equipment, as well as Christmas gifts to local schools; the provision of transport for school learners to attend extra classes during the holidays and the North West University’s open day; and the establishment of a local soccer league of twelve teams with sponsored kits, equipment and tournaments.

Then when load shedding affected local water supply, WBHO and Sola stepped in and supplied generators for the pumps and assisted in distributing water in the community.

For a period of six weeks, 46 million litres of water was supplied to the entire town of Lichtenburg and surrounding areas.

Another initiative that set the Lichtenburg project apar t was the months of training offered to SMMEs in the community. Senior WBHO personnel instructed emerging local businesses through management, marketing, logistics and other more technical construction-related courses. It was extended into a mentorship programme, which included on-site work training.

Adds Greig Bastion, WBHO project director for these PV projects “Big projects have the potential to leave a community with a better economy, better skills, and with better infrastructure, but also with hope and trust – we are all building a better place together.”

The Merak 2 and 3 PV project covers an area of approximately 4 km2 and was executed by Wilson Bayly Holmes-Ovcon (WBHO) Construction, together with its joint venture partner, the Sola Group, in 2024

38 IMIESA May 2024

RENEWABLE ENERGY & ELECTRIFICATION

Digital solutions that lower building footprints As increasing emphasis is placed on the global drive towards net zero carbon emissions, ever y industr y is being challenged to lower its carbon footprint and adopt sustainable practices, buildings being a prime example.

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ccording to a United Nations report, as of 2020 buildings account for some 37% of global energy use and energyrelated CO2 emissions.

“As such, sustainable building practices are likely to see buildings of the future depending more on renewable energy sources rather than on traditional electricity grids. Electricity grids

in many regions – including South Africa – are still hugely coal-fired and thus detrimental to the environment,” says Mark Freeman, Offer Manager Digital Buildings for Anglophone Africa at Schneider Electric.

The only way to achieve this level of efficiency is through digitising a building to ensure the utilisation of the right power loads and the right power sources, at the right time, says Freeman. “Buildings of the future will not only have visibility of the power they consume but also where they are consuming it, how they are consuming it and which source it is coming from for specific applications.”

Mark Freeman, Offer Manager Integrated building management Digital Buildings systems provide actionable insights for Anglophone to manage buildings efficiently, Africa at Schneider improve engineering efficiency and Electric meet cybersecurity needs. These platforms integrate multiple systems for centralised, real-time control and management across one or several enterprise buildings.

Energy supply management Additionally, developers can integrate energy supply management software solutions

into their buildings that are designed to help power-critical and energy-intensive facilities maximise uptime and operational efficiency, says Freeman. These solutions can provide insight into electrical system health and energy efficiency, allowing informed decisions to be made that improve performance.

“From a single pane of glass, building managers can operate and manage ever y system and application, such as smar t electricity and water meters, pump and HVAC systems and building security, among others.

Not only can the switch-on and switch-off times be set for specific periods, but smart building solutions can also manage and switch between power sources for different systems, as and when needed,” Freeman explains.

Schneider Electric’s innovative solutions, such as EcoStruxure Building Operation, EcoStruxure Power Monitoring Expert, as well as other advanced offerings, are instrumental in steering developers towards a future where technology seamlessly integrates with the built environment.

“As electricity prices continue to rise and the transition to net zero carbon emissions becomes more pronounced, building owners will increasingly look to systems that will enable them to make educated and informed decisions about their energy options. Smart digital solutions can convert data into action and unlock a building’s energy management system’s full potential with advanced energy visualisation and analysis tools,” Freeman concludes.

IMIESA May 2024

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HAVE YOU REGISTERED FOR THE 87TH IMESA CONFERENCE YET?

2024

IMESA

CONFERENCE ENGINEERING REVOLUTIONISED

CAPE TOWN 6-8 NOVEMBER

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CRUSHING & SCEENING

Astec’s robust GT range proves its mettle The first GT205 mobile screen track unit commissioned in South Africa was supplied by Astec Africa and Middle East (AME) to longstanding customer Lizarox at the end of 2023

With South Africa’s construction industry facing challenges that include the rising costs of materials, labour and equipment, along with reduced budgets and opportunities, stakeholders across the value chain are under pressure to reduce costs and increase productivity.

I

n the concrete sector, producers of aggregate, which is the foundation of every construction project, are rising to the challenges by choosing flexible, multipurpose equipment that is robust, long wearing and simple to operate and maintain, like Astec Industries’ GT125 mobile jaw crusher and GT205 mobile screen.

The first GT205 mobile track unit commissioned in South Africa was supplied by Astec Africa and Middle East (AME) to longstanding customer Lizarox at the end of 2023. It is proving more than up to the task at a leading quarry in Ladysmith, KwaZulu-Natal.

Described by Lizarox director Michael Crackett as a “screening beast”, the Astec GT205 is being used in a two-stage and multi-stage crushing and screening application for the production of layer works materials such as G5 and G2, as well as single size aggregates for use in concrete and asphalt.

Lizarox chose the Astec GT205 because the screen is robust, and its operation is straightforward, Crackett says. “Certain competitor products are unnecessarily complicated. The maintenance of some equipment is difficult as a result of the logistics challenges experienced globally since the Covid-19 crisis.

“Astec’s backup on our existing equipment has always been excellent. When faced with challenges in the past, they always stepped up to the plate.

This remains the case today and provides us with a sense of comfort that we are in good hands when it comes to product reliability and backup service.”

Screen box setup Lizarox also favoured the GT205’s large screen box.

“This enables the production of high volumes of material when producing straightforward products such as G5. But, with the three-deck four-product conveyor setup, there is also an element of finesse available when coupled with the height and angle adjustable screen box. This functionality allows us to maximise high quality low yield products such as 7 and 10 mm surfacing stone,” Crackett states.

The three-deck mobile unit is fitted with a 5 x 20 screen and a Caterpillar C4.4 129 HP Tier III diesel engine. The screen’s gradation control allows for reclaiming fines in both wet and dry applications.

Astec mobile incline screen plants have an array of features for maximum screening efficiency and production. Astec Industries regional sales manager Casper Booyse expands: “Astec screen plants are engineered to provide higher production capacities and more efficient sizing than

comparable screens. Our mobile plants combine heavy-duty screens with industry-leading conveyor heights. A large range of media provides flexibility for a variety of applications.”

GT125 mobile jaw crusher versatility Equally effective in aggregate and recycling applications, Astec’s GT125 is built for maximum jaw crushing mobility. This robust crusher is making its mark around the world, especially in the United States, where its applications include producing and recycling aggregate.

The GT125’s large, dynamically balanced, heavyduty flywheels produce up to 33% more inertia than competitive models, leading to a reduced cost per ton over the lifetime of the machine. Furthermore, the crusher’s large, 32 mm stroke processes more material than competitive models, increasing production and reducing operating costs. A simple manual folding head section on the discharge conveyor reduces the footprint of the machine, reducing shipping costs.

Like all Astec equipment, the GT range has comprehensive aftersales support, service and spares availability across Africa and in the Middle East. This is delivered by Astec Industries AME and its growing network of qualified dealers across these regions.

The GT125’s large, dynamically balanced, heavy-duty flywheels produce up to 33% more inertia than competitive models, leading to a reduced cost per ton over the lifetime of the machine

IMIESA May 2024

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ASPHALT & CONCRETE PLANTS

PIONEERING PROGRESS

Lintec & Linnhoff’s commitment to African infrastructure development The African continent is a key region for Lintec & Linnhoff, representing one of the company’s largest markets.

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ere Lintec & Linnhoff asphalt mixing and concrete batching plants are hard at work in several African countries, thanks to our world-renowned reputation as a global leader in the manufacturing of construction equipment solutions, as well as pre and after-sales customer service.

Lintec & Linnhoff is backed by 100 years of collective German expertise, and our brands provide powerful and innovative solutions that meet industry standards for environmental impact, recyclability, and reusability for thousands of prestigious infrastructure projects worldwide.

Our presence at Big 5 Construct South Africa 2024 is a testament to the importance we place on the African market. The exhibition plays a key role in allowing us to strengthen our connection with our customers in their home markets. Our customer relationships are built on quality, trust, and service, with the exhibition serving as a platform to engage in conversations that help us understand their needs and help them improve their operations.

Over recent years Lintec & Linnhoff has expanded its business in multiple markets in Africa and is well-represented across the continent through dealership agreements with partners in Egypt and Nigeria with plans to further expand our distributor network this year.

This Lintec CSD2500B Containerised Asphalt Mixing Plant produced hot mix asphalt for surfacing work on a 14.2 km highway construction project in Abidjan

Leading projects Lintec & Linnhof f’s asphalt mixing and concrete batching plants have completed many major construction projects across African countries. These include Gabon where the Lintec CDP12001M Continuous Asphalt Mixing Plant supported the construction of a municipal project producing 100 -120 tons of hot mix asphalt per hour; Côte d’Ivoire where a Lintec CSD2500B Containerised Asphalt Mixing Plant produced hot mix asphalt for surfacing work on a 14.2 km highway construction project in Abidjan; Madagascar where a Lintec ECP60 Concrete Batching Plant was used by a Japanese contractor for the redevelopment of the Toamasina Port project; and Mali where

A Lintec CSM4000 Containerised Asphalt Mixing Plant commissioned in Cameroon to build the country’s first-ever expressway

a Lintec ECP90 supplied high-quality concrete to local contractors to support the nationwide push to increase public housing construction.

Fur ther examples include Egypt where a Lintec CSD2500B Containerised Asphalt Mixing Plant completed its first job on an impor tant municipal highway contract in Aswan; Cameroon where a Lintec CSM4000 Containerised Asphalt Mixing Plant was commissioned to build the country’s first-ever

ASPHALT & CONCRETE PLANTS

A Lintec ECP90 concrete batching plant commissioned in Mali. This plant supplies high-quality concrete to local contractors to support the nationwide push to increase public housing construction

In addition, the Lintec CSD Containerised Asphalt Mixing Plants are built in ISO-certified sea containers and are the first of their kind in the industry. The Lintec CSD Asphalt Mixing Plants feature a modular construction that allows for easy transportation and convenient installation, representing the ideal choice for both small and big project requirements.

The Linnhoff NVX NovaMax Asphalt Mixing Plants are designed for the most efficient asphalt mixing operation with hot elevator and vibrating screens. Its modules are configured for quick installation and compact footprint, making it an economical asphalt mixing plant suitable for any paving project.

Supporting growth expressway; Ghana, where a Linnhoff TSD1500 MobileMix Asphalt Mixing Plant achieved remarkable progress on a high-profile road project; as well as Ethiopia where the Linnhoff TSD 1500 MobileMix Asphalt Plant worked on Ethiopian roads and highways.

Showcased at Big 5 Construct South Africa At this year’s Big 5 Construct South Africa, we will be promoting our popular range of TSD, CDP, CSD, and NVX models.

The Linnhoff TSD MobileMix Asphalt Mixing Plant is ideal for short-term projects when time is of the essence. Featuring our trademark double-screen drum technology, the Linnhoff TSD range reduces overall operating costs and fuel consumption by eliminating the need for hot elevators and vibrating screens. They are also designed with four fully integrated basic mobile modules, with a built-in chassis for easy mobility.

The Lintec CDP series of continuous asphalt mixing plants ranges from 30-160 tph. They can be assembled on a suitable and solid compacted ground, without the need for concrete foundations. They are conceptualised for easy and quick set-up and dismantling, making them suitable for short-term projects or mobilisation from one project to another.

With a capacity that ranges from 80 tph to 240 tph, and batch sizes from 1350 kg to 3 000 kg, Lintec’s CSD Asphalt Mixing Plants offer superior and unique energy-saving technology that brings cutting-edge sustainability, low total cost of ownership, and reduced energy consumption. In addition, all plants are preassembled to undergo rigorous test cycles, ensuring quality as well as fast and smooth setup, low shipping costs, and efficient transportation.

According to Mordor Intelligence, the Africa Construction Market size is valued at USD 58.42 billion in 2024 and is expected to reach USD 74.81 billion by 2029, growing at a CAGR of 5.07%. With this in mind, Lintec & Linnhoff remains firmly committed to the region and will continue to listen and respond to the needs of our customers by providing industr y-leading solutions that offer exceptional solutions for infrastructure projects in African countries.

A Lintec CSD2500B Containerised Asphalt Mixing Plant. This unit was sold to an Egyptian contractor and completed its first job on an important municipal highway contract in Aswan

IMIESA May 2024

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CEMENT & CONCRETE TECHNOLOGY Mapei’s Mapecrete System is the ideal solution for creating concrete industrial flooring without control joints

Admixtures

MAKE CONCRETE WORK Providing physical as well as economic benefits, the role of admixtures in the concrete mix is a key factor in ensuring downstream quality and structural integrity, but it’s a complex science – and application specific. IMIESA speaks to Servaas Le Roux, Product Line Manager – Concrete Admixtures at Mapei South Africa about their solutions in the drive to achieve optimum concrete workability.

M

apei made its entr y into the admixture and construction chemicals segment globally in 1992 with the milestone introduction of the first ever acrylic based (polycarboxylate ether or PCE) superplasticiser in Europe. Over time, Mapei’s admixture range has grown extensively and now caters for a broad market spectrum of project and product applications, from precast manufacturing to readymix production and on-site concrete batching.

A liquid admixture, developed through modification to acr ylic polymers, PCE represents the third generation in the development of admixtures globally

44 IMIESA May 2024

by construction chemical producers.

Optimum water reducers, they are ideal for applications that include high-strength and high workability concrete.

PCE was preceded by first and second generation plasticisers, using lignosulphonate and naphthalene organic compounds, respectively. Lignosulphonate is a byproduct of the pulp and paper industry, while naphthalene is sourced as a coal or petroleum byproduct. As mid-range water reducers, their role in influencing the water to cement ratio is around 5-10% and 10-20%, respectively, compared to superplasticisers that can achieve around a 20-30% water reduction.

“In all cases, these plasticising admixtures provide a temporar y dispersing ef fect, improving the flowability of the concrete within the required placing window (or open time as it’s referred to in industr y), and ultimately enhancing cement hydration,” Le Roux explains.

However, since its introduction to the construction industry, the field of concrete admixtures has developed to the point where it now also offers many secondary effects to a concrete manufacturer. These could include either accelerating or decelerating the concrete setting time; reducing water content; increasing the initial and/or final concrete strength; reducing thermal cracking by countering early heat of hydration; minimising segregation or bleeding; enhancing pumpability; to compensate for poor aggregate proper ties; as well as to lower the overall cost of the cement paste employed. The latter constitutes 25% to 40% of the total volume of concrete.

In Mapei’s Concrete Admixture line, 70% fall into the plasticiser/superplasticiser categor y, with the remaining 30% comprising ancillary products that support the main line.

CEMENT & CONCRETE TECHNOLOGY “For South Africa, we mostly supply hybrids: a combination of lignosulphonate and PCE. Naphthalene has separate, unique applications for products that include clay mitigation and shotcreting,” says Le Roux.

Product examples from the Mapei admixture series include: • T he Dynamon Easy range: this hybrid solution is aimed at clients that include readymix producers and contractors (par ticularly on largescale projects).

They meet EN934-2 and SABS 5093-2 specifications, and are manufactured according to ISO 9001, 14001 and 45001.

• The Dynamon Xtend range: this is a pure PCE product, used in applications where a high degree of extended open time is required.

• The Dynamon precast range, which offers extremely high water reduction coupled with moderate open time, which is required in most precast facilities. An example is the construction of on-site precast prestressed bridge beams where maximum water reduction is required.

• The Mapeplast range: these are first generation plasticisers containing lignosulphonate, of fering a robust plasticising effect. Product applications include slipform paving; and flatwork, curb mixes and walls, where they enhance finish quality.

In turn, ancillary products include: • The Mapeform range, which offers mould release agents with either organic or oilbased base materials.

• The Vibromix range, used in the production of various vibrated concrete products, especially when zero or low slumps are required.

• T he Mapecure range of curing and sealing compounds.

• The Mapefibre range, with a wide variety of polypropylene, polyolefin and steel fibres designed to improve aspects ranging from plastic shrinkage control in concrete to energy absorption in shotcrete or unreinforced concrete jointless flooring.

•R etarders and accelerators, and • Mapeair air-entraining admixtures or foaming agents, which are well-suited for improving low quality aggregates or to mitigate freeze-thaw effects onto concrete structures.

composition of the final product, they are the essential ingredient in the overall concrete design, but which ones to select is the key.

“In terms of the professional services we offer, the starting point is a detailed client consultation about the required outcome on a specific product or project outcome basis. In this respect, it’s essential to verify the quality of the raw materials being used at source – the aggregates and binder – because that determines the admixture inter ventions required, plus the degree of acceptable volatility,” Le Roux continues.

“Having access to high quality aggregates is not always possible, particularly in remote areas. Subsequently, variations in quality can result in gap grading variances (the distribution of fine, medium and coarse particle sizes within an aggregate sample) that will influence concrete quality unless suitably treated with an admixture and/or ancillary products,” he explains.

“Essentially, this entails modifying the amount of cementitious material and water needed to make the mixture workable.

Where available, well graded aggregates are best because they improve workability and require less cement to achieve the desired strength.”

Professional advice and raw material analysis While concrete admixtures typically comprise less than 3% volumetric Mapefibre macro synthetic fibres for concrete

Application specific That’s why ever y situation calls for a unique approach. For example, a precast manufacturer in Gauteng, with a similar operation in the Western Cape fabricating the same product, might require a different admixture based on factors like local ambient temperatures and raw material variances.

“This requires a flexible and innovative approach from our side on a case-by-case basis because our client’s raw material sets can change depending on where they secure work and based on the specific concrete mix design parameters. So, it’s not a blanket approach,” Le Roux stresses.

Examples would include changing binder requirements like the inclusion of ground granulated blast furnace slag or fly ash additives. This will influence the admixture cement interaction, which might result in excessive bleeding or poor to no workability, for example, if not addressed. High ambient temperatures will exacerbate the issue.

Laboratory trials and dosing To verify the process, Mapei South Africa’s in-house laborator y at its Germiston headquar ters in Gauteng provides a comprehensive aggregate analysis service, which is supported by the local research and development team.

All clients are supplied with a purposedesigned and maintained Mapei admixture dosing system to eliminate the risk of under or overdosing for each specified precast, readymix or in-situ concrete application. Around 2 - 3 litres of admixture for 1 m3 of concrete is a typical requirement.

“Today, admixtures play a role in all concrete production and are a vital ingredient. At Mapei we are dedicated to working with our clients to develop the most cost-effective solution that maximises durability and the lifespan of building and infrastructure assets,” Le Roux concludes.

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CEMENT & CONCRETE TECHNOLOGY

CORESTRUC SCORES ANOTHER GOAL FOR PRECAST CONSTRUCTION The new precast concrete grandstand at the upgraded Richards Bay Football Club in KwaZulu-Natal is the largest and most recent to be built by Corestruc. It is able to seat the many fans of the soccer club, which secured its second season in DSTv’s Premier Soccer League in 2023.

The grandstand is founded on CFA piles

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onsisting of more than 800 precast concrete elements and 22 grids, the prefabricated concrete structure is 14,9 m in height at the back columns and 121 m in length.

Impressively, it was constructed in only four months after the in-situ footings were completed. This was achieved while working alongside the principal contractor, Trillionaire Group, which was appointed by uMhlathuze Local Municipality to upgrade this sports and recreational centre.

Piling commenced in March and was completed in May. However, due to persistent heavy rain through to July, progress was stifled, with actual integration of the precast concrete elements only commencing that month.

Geotechnical investigation After considering the geotechnical report supplied by the client, a more extensive geotechnical investigation was required to

46 IMIESA May 2024

Installation of the seating benches in progress

determine the deeper subsoil conditions.

This was undertaken with the assistance of the appointed piling contractor, Mega Pile.

Further geotechnical investigations provided sufficient information to finalise the CFA pile design. This is with regards to the specified design loading that had to be transferred from the precast concrete frame structure, via the in-situ cast concrete stub-columns and ground beam sub-structure, to the CFA piles.

Precast design methodology The rapid rate at which the company can construct these structures has been facilitated by a unique design that has been per fected over many years. Corestruc’s standardised system can be quickly and efficiently modified to suit most municipal requirements during the design phases.

This enables the manufacture of the system to commence as early as possible. In this way, the various precast concrete elements that make up the system are ready to be dispatched to site as and when they are

required once the ear thworks and site terracing have been completed.

Moreover, Corestruc’s design facilitates quick and efficient integration of the precast concrete grandstands. What took the company only a few months to construct would have otherwise taken a year had traditional castin-place concrete methods been used to build the large grandstand in Senwabarwana.

Time spent on site has been significantly reduced by standardising and minimising the number of precast concrete elements that make up the grandstand. Curved columns and rakers, benches and side panels also facilitate quick and efficient installation.

Simplified connections To fur ther streamline construction, the manner in which the various precast concrete elements are connected has been simplified.

The columns are connected to the in-situ bases by components that have been cast into the precast concrete elements. They are then secured using hold-down bolts in the

CEMENT & CONCRETE TECHNOLOGY

bases. The raker beams, seating benches and side panels are secured with strategically positioned dowels. They fit seamlessly into the sleeves that have been cast into the various precast concrete elements and into which the grout is then poured.

The high accuracies achieved when designing the grandstands and executing these in the precast concrete factories during the manufacture of the different concrete elements also streamline construction.

BIM approach Corestruc’s engineers use sophisticated commercial software for structural analysis and design. Building Information Modelling (BIM) systems are deployed to model the structures and each precast concrete element.

BIM improves quality control by enabling seamless tracking and tracing of ever y precast concrete element from their design phase through to integration on site. It also facilitates quick and efficient communication between all stakeholders. This includes clients and their implementing agents; consulting engineers; principal contractors; and the specialist precast concrete subcontractor, as well as its engineers which lend additional technical support.

To further ensure accurate manufacture of the precast concrete elements, forms have been manufactured from steel that has been cut with laser-cutting machines. Considering that quick turnaround time is important to avoid delays, they have also been designed to facilitate the accurate placement of the various cast-in components. Moreover, computerised batching plants facilitate optimised curing processes to further reduce lead times.

Total quality control In addition to those deployed in the precast concrete factories, quality control checks

are conducted after the transportation of the prefabricated concrete elements to site.

This is another important component of the precast concrete value chain over which Corestruc has complete control. The precast concrete elements are carefully loaded onto and affixed to the company’s tri-axle flatbed trailers. Although they have had enough time to harden fully, extreme caution must still be exercised to avoid damaging them.

As an additional precautionary measure, quality control is also undertaken during the various phases of construction.

Considering the precise design and manufacturing processes deployed, Corestruc’s riggers achieve tolerances of 5 mm when connecting the columns to the foundations and 5 mm when integrating the other components of the system.

predominantly constructed using structural steel with sheet metal as the cover.

Corestruc’s system is up to 40% more cost-effective than in-situ construction.

This is achieved by eliminating the need to manufacture bespoke shutters and operating a tower crane for almost 12 months on site, among other preliminary and general costs associated with such a project.

Moreover, by standardising the system, Corestruc can fix construction costs. This facilitates accurate budgeting and avoids cost overruns.

Precast concrete also addresses the delicate cost concerns associated with scheduling a typical cast-in-place construction project. By eliminating logistical concerns, scheduling becomes easier which, in turn, helps to ensure that unexpected costs do not accrue.

Installation The middle columns are the first to be placed.

They are set out with coordinates to confirm the plumb and position. The front raker beams are then aligned with the top and bottom bolts of the columns and fastened in place.

Corestruc then places the rear columns and braces them with structural steel. This provides the necessary stability at this stage of construction considering the slenderness of the columns. The top raker beams are then installed in the same way that the front elements are placed. Afterwards, they are braced horizontally in a similar sequence to that used for the back columns.

This is followed by the placement of the seating benches. They are lined up with the raker beams and then grouted into position and, in doing so, form a single monolithic structure. Thereafter, the side panels and steps are installed. The roofs of the structures vary from one sports and recreational centre to the next, but are

Durable and sustainable Designed to continue adding value for at least 100 years with minimal maintenance, Corestruc’s precast concrete grandstands are of an exceptionally high quality. This reduces maintenance costs for municipalities. Considering that less construction materials are required to maintain these structures over their long useable life, this also reduces the already lower carbon footprint of the company’s unique grandstands.

“Our precast concrete system has become the preferred method of building grandstands for municipal spor ts and recreational centres. This is considering the speed at which they can be constructed and the savings that they provide municipalities, both in terms of construction and operating costs over their long useable life,” Willie de Jager, Managing Director of Corestruc, concludes.

The prefabricated concrete grandstand structure is 14,9 m in height at the back columns and 121 m in length

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managing director of BLOCK PLAN. “We did this by placing the main body of the columns outside rather than on the inner side of the walling. This structural rhythm was further enhanced by capping off the walls with 8 m L-beams. The 300 mm upstand width of the beams mirrors the width of the columns and this gives the walls a very uniform concrete coping on all elevations. Moreover, the beams create a horizontal framework, which forms a pleasing contrast to the vertical column work.”

Some of the northern elevation columns showing the vertical slots for the insertion of the hollow-core slabs

Optimising space

NEW CAPE WAREHOUSE BUILT WITH PRECAST PRECISION Reserve-5, an attractive 5 500 m² distribution warehouse in Brackenfell, Cape Town, has been built with several precast concrete elements supplied by Concrete Manufacturers Association member, Cape Concrete Works. Completed in December 2023, Reserve-5’s precast components comprise columns, hollow-core slabs for walls and flooring, and precast stairs.

T

his is no ordinar y distribution centre. Visually striking and pleasing to the eye, precast concrete has been skilfully deployed as an aesthetic, as well as a structural component by architects

BLOCK PLAN. What’s more, of the 45 precast columns supplied by Cape Concrete, only two were placed inside the building for roof support.

“We were able to create a sense of rhythm across all elevations,” says Gordon Hubbard,

The wall columns were cast with vertical slots from top-to-bottom to accommodate the wall slabs, and by positioning the body of the columns outside rather than inside the walls, more internal space was generated. Additional space was achieved by restricting the number of internal columns to two.

Cape Concrete installed all the precast concrete elements and the consulting engineers, Ekcon, handled the structural engineering.

Construction began with the installation of the columns. Spaced at 8 m intervals across all four elevations, the columns created a framework for the installation of the wall slabs and the roof assembly. Using the Peikko bolting system, galvanised steel shoes were cast into the bottom of the columns and matching steel bolts were attached to the column footings. The bolts were spliced with the footing reinforcing, a process which required great precision. And to this end, Cape Concrete provided the contractors with templates to ensure that the footing bolts were placed accurately.

Lifting pins Cape Concrete also cast two lifting pins into each column, which were neatly grouted once the columns had been installed. The pins

Some of the southern elevation columns with hollow-core slabs in the foreground prior to installation

48 IMIESA May 2024

The partially complete southern elevation hollowcore wall

CEMENT & CONCRETE TECHNOLOGY The partially completed warehouse showing the masonry walls of the office components on the left and right of the picture

enabled a mobile crane to lift the columns off the truck beds and lower them into position over the footing bolts. Once column alignment had been adjusted with spacers, steel nuts were attached to the bolts to lock the columns permanently into position.

Roofing girder Before the hollow-core walling panels were inserted between the columns, a central heavy-duty roofing girder was assembled on the building’s east-west axis. The girder was supported by the two internal columns and two wall columns. Thereafter lighter steel sections were bolted onto the girder and some of the walling columns. Cape Concrete cast steel brackets into these columns to facilitate the attachment of the steel roof sections.

Warehouse structure The warehouse has a floor-to-roof height of 11 m and all the perimeter columns are 11 m high. The two internal columns comprise 8,3 m concrete columns mounted with 2,7 m steel sections. PVC 200 mm rainwater downpipes were cast into the two internal columns. This is because the roof falls towards the mid-point and all rainwater drains into the downpipes and then into drainage pipes embedded in the flooring.

Once all the wall panels were in place, Cape Concrete installed the L-beams, which were attached at either end with Y16 dowel bars.

Occupation and layout Reserve-5 was built for two tenants, which was why it is split into two sections, at a two-to-one third ratio. The sections are divided by a brick wall, which runs on a nor th-south axis. The larger unit was built with four vehicle access doors and the smaller unit has two. The doors measure 5,5 m in height and

Three of the four entrances to the larger warehouse

4,2 m in width and two of the doors in the larger unit were built adjacent to each other.

Solid, rather than hollow-core panels were inser ted above each door. These were required for bolting on the roller shutter door equipment. The construction of the frames for these doors also required shorter columns and hollow-core slabs, which were supplied by Cape Concrete.

Each distribution section has a two-storey office component, which is housed inside the greater building with floor footprints of 170 m² and 300 m² apiece. Cape Concrete’s hollow-core slabs were used for constructing the first floor and roof sections in what were other wise conventional brick and mortar structures.

Just under 9 m long and 1,2 m wide, the slabs were designed to carry 250 kN so that the roof section of each can be used for additional storage. Furthermore, Cape

Concrete supplied eight precast concrete staircases for the office structures.

Cape Concrete also supplied 10 solid panels with recesses for the installation of aluminium window frames. Installed at the upper level of the northern elevation, the windows provide the building with natural light.

Time and quality Hubbard says the use of precast concrete in Reserve-5 halved the construction time. “It took only three weeks to install the columns and the walling as opposed to three months had in-situ concrete been used. Likewise, the use of hollow-core slabs in the office sections saved several weeks.”

“Besides other benefits such as standardisation and better quality control, we were very happy with the quality of the precast concrete elements. Working with Cape Concrete is a pleasure. Always willing to compromise, they are always happy to sit around the table and resolve any outstanding matters,” Hubbard concludes.

The completed structure

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CEMENT & CONCRETE TECHNOLOGY

The formulation of AfriSam Roadstab Cement aims to address the vital requirements of road construction projects by ensuring the durability and stability of road bases

AfriSam Roadstab Cement enhances durability

A

friSam Roadstab Cement is a specialised, high quality composite cement engineered specifically for road stabilisation tasks. Available from leading construction materials supplier, AfriSam, this cement is designed to optimise the properties of soils used in road construction, notably by reducing their plasticity and enhancing their strength and stability.

The unique composition contributes to its efficacy, particularly in working with challenging soil types like clay. This addition not only improves the workability of the cement in various soil conditions but also facilitates easier handling and application during the construction process.

Stabilisation using cement also improves the proper ties of granular materials. When cementitious material is mixed with granular material in predetermined portions and is adequately mixed, compacted and cured, a bound material with significant strength is the result.

An impor tant advantage of AfriSam Roadstab Cement is its extended open working times as it provides ample time for the proper placement and compaction of materials. This type of flexibility in the construction timeline is crucial for achieving optimal results, ensuring that the stabilised layers meet the required standards for strength and durability.

IMIESA May 2024

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CEMENT & CONCRETE TECHNOLOGY

SPUN CONCRETE ELECTRIFICATION POLES ADD VALUE Multi-billion rand losses due to illegal electricity connections is a growing issue in South Africa, with knock on effects for society and the economy in terms of intermittent power outages. There are also downstream safety issues such as electrical fires and electrocutions.

T

o provide an effective solution, Rocla fields a range of spun concrete electrification poles designed to withstand vandalism risks, as well as providing a more durable solution compared to wooden alternatives.

Approved by Eskom’s Rosher ville Testing Station, a key advantage of these poles is that they are exceptionally strong through 360 degrees, whereas normal cast concrete poles have a major and minor load axis. In contrast, Rocla’s unique centrifugal manufacturing process provides a uniform densely compacted concrete along the whole length of the pole. This results in superior strength proper ties, plus lifespans exceeding 50 years with minimal maintenance.

Rocla of fers a variety of pole lengths in single, jointed, and double pole configurations, with custom options available to meet specific customer

sizing requirements. Applications include transmission and distribution power lines, telecom masts, lighting, security monitoring and stadium use.

Rocla offers a variety of pole lengths in single, jointed, and double pole configurations, with custom options available to meet specific customer sizing requirements

Sicelo informal settlement Demonstrating its design flexibility, Rocla (forming part of the IS Group that includes Technicrete), has recently provided a range of solutions for Lyon and Par tners Consultants at the Sicelo informal settlement, near Vereeniging, Gauteng.

“The implementation of electricity supply to Sicelo was a project that needed a customised electrification concrete pole solution. Our technical team met with the consultants and the engineers for the Sicelo informal settlement project and under took the manufacture and supply of their final design specifications required for this five-phase project,” explains Kevin West, a Rocla sales consultant.

“Our ability to customise, manufacture and deliver over 105 concrete spun electrification poles within the required timeframes was a key factor to our successful partnership,” he continues.

The products supplied for all phases comprise 11 m/160 mm tip/8.5kN spun poles and 9 m/160 mm tip/8.5kN spun poles.

“A safe electricity supply to informal settlements is a priority. It uplifts the community, and we are a proud par tner to Lyon and Par tners in the supply of infrastructure that meets their objectives,” West concludes.

INDEX TO ADVERTISERS OFC, 6

IMESA

4, 40, 50

Astec Industries

19

JPCE

25

EnviroServ

IFC

Lintec & Linnhoff

Gabion Baskets

17

Maccaferri

AfriSam

52 IMIESA May 2024

Mapei

13

Rainbow Reservoirs

31

OBC

SBS Tanks

2

9

Terraforce

21

IMESA The official magazine of the Institute of Municipal Engineering of Southern Africa www.imesa.org.za

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