IMIESA April 2023

www.infrastructurenews.co.za

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

INFRASTRUC TURE DEVELOPMENT • SERVICE DELIVERY • ROADS • BUILDING • MAINTENANCE • ENERGY

Roads & Bridges New frontiers in digital engineering

Trenchless Technology Factors to consider when lining pipelines Stormwater & Drainage Sustainable attenuation ponds

Waste & Recycling Stemming the flow of e-waste to landfills

APE Pumps & Mather+Platt Success founded on passionate employees

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INSIDE

VOLUME 48 NO. 03 APRIL 2023

32 Regulars www.infrastructurenews.co.za www.infrastructurenews.co.za

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

INFRASTRUC TURE DEVELOPMENT • SERVICE DELIVERY • ROADS • BUILDING • MAINTENANCE • ENERGY

Roads & Bridges New frontiers in digital engineering

Trenchless Technology Factors to consider when lining pipelines Stormwater & Drainage Sustainable attenuation ponds

Waste & Recycling Stemming the flow of e-waste to landfills

APE Pumps & Mather+Platt Success founded on passionate employees

Editor’s comment President’s comment Index to advertisers

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Cover Story Success founded on passionate employees

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Thought Leadership PPC’s strength and vision supports African infrastructure expansion

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Energy & Electrification I S S N 0 2 5 7 1 9 7 8 Vo l u m e 4 7 N o . 0 1 • J a n u a r y 2 0 2 2 • R 5 5 . 0 0 ( i n c l . VAT ) I S S N 0 2 5 7 1 9 7 8 Vo l u m e 4 8 N o . 0 3 • A p r i l 2 0 2 3 • R 5 5 . 0 0 ( i n c l . VAT )

ON THE COVER

Testbed investment in battery storage technology More time to prepare for EPC compliance

Companies that consistently perform and deliver exceptional customer service in their niche markets have an infinite life. A prime example is the legendary history of APE Pumps and sister company Mather+Platt, which have been pump leaders in South Africa since 1952. General manager John Montgomery profiles some of the key men and women who continue to shape the group’s future. P6

Unique AKS system keeps concrete protected for longer

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40

TRENCHLESS TECHNOLOGIES

50

VEHICLES & EQUIPMENT

34 36 40 42

46

Sustainable attenuation pond designs in precast concrete

47

Water & Wastewater 18

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Urban wetland management is now crucial Closing the gap: access to water

48 49

Vehicles & Equipment Bell cuts new path with own grader series Green asphalt delivery on Chinese expressways

22

Cement & Concrete

24 27 27

Concrete knowledge vital for safe and reliable infrastructure Kariba Dam rehabilitation project progresses Desert bridges get extensive overhaul

Roads & Bridges New frontiers in digital engineering Sanral reports strong project pipeline N4 slow lane upgrade now well advanced

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Stormwater & Drainage

Road Construction | Technologies, Standards & Specifications When it comes to quality, durability and sustainability are interlinked

Trenchless techniques have proven advantages that need exploring Design considerations for new pipelines and rehabilitating pipelines with linings Novel culvert jacking project showcases creative thinking Slurry microtunnelling solutions for SA hard rock conditions

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Contracts & Intellectual Property Procurement as the basis for theft and extortion

South Africa’s largest biofiltration plant now operational

Lining Systems | Corrosion Protection

Waste & Recycling Stemming the flow of e-waste to landfills and extracting sustainable value

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Metro: Nelson Mandela Bay

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Urban Development & Renewal 22 years of managing capital expenditure projects

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Trenchless Technologies

Africa Round-up Infrastructure news from around the continent

Doing more for our asphalt industry Customer appreciation day for asphalt clients

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CEMENT & CONCRETE

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QUALITY & RELIABLE

MODULAR ASPHALT SOLUTIONS Linnhoff was established in Germany in 1919. Apart from being one of the oldest names in the industry, it is also a leading brand of asphalt mixing plants. Word of our quality and reliability has spread as far and wide as the roads paved by the hot mix asphalt produced with Linnhoff asphalt mixing plants over the last century.

EDITOR’S COMMENT MANAGING EDITOR Alastair Currie SENIOR JOURNALIST Kirsten Kelly JOURNALIST Nombulelo Manyana EDITORIAL COORDINATOR Ziyanda Majodina HEAD OF DESIGN Beren Bauermeister CHIEF SUB-EDITOR Tristan Snijders CONTRIBUTORS Burgert Gildenhuys, Alaster Goyns, Sibusiso Mjwara PRODUCTION & CLIENT LIAISON MANAGER Antois-Leigh Nepgen GROUP SALES MANAGER Chilomia Van Wijk BOOKKEEPER Tonya Hebenton DISTRIBUTION MANAGER Nomsa Masina DISTRIBUTION COORDINATOR Asha Pursotham SUBSCRIPTIONS subs@3smedia.co.za ___________________________________________________ ADVERTISING SALES KEY ACCOUNT MANAGER Joanne Lawrie Tel: +27 (0)11 233 2600 / +27 (0)82 346 5338 Email: joanne.lawrie@3smedia.co.za ___________________________________________________

PUBLISHER Jacques Breytenbach 3S Media Production Park, 83 Heidelberg Road, City Deep Johannesburg South, 2136 PO Box 92026, Norwood 2117 Tel: +27 (0)11 233 2600 www.3smedia.co.za ANNUAL SUBSCRIPTION: R600.00 (INCL VAT) ISSN 0257 1978 IMIESA, Inst.MUNIC. ENG. S. AFR. © Copyright 2023. 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: Ollah Mthembu Tel: +27 (0)82 823 7104 Email: np@imesa.org.za SOUTHERN CAPE KAROO Secretary: Henrietta Olivier Tel: +27 (0)79 390 7536 Email: imesasck@imesa.org.za WESTERN CAPE Secretary: Michelle Ackerman Tel: +27 (0)21 444 7114 Email: imesawc@imesa.org.za

Getting SOEs to work

T

he recent announcement that the South African Post Office (SAPO) has been placed under provisional liquidation doesn’t come as a surprise, but it’s concerning for the country and SAPO’s employees.

As with many other state-owned enterprises (SOEs) like Eskom and SAA, progressively poor administration over many years has inevitably brought SAPO to this point.

But it doesn’t have to signal the end and it shouldn’t because SAPO has historically been the backbone of our interconnected society, providing an invaluable service, including a savings bank.

However, the only way to financially resuscitate SAPO is to ensure that it has a saleable service the market still wants.

Plus, instead of trying to go it alone, there are major opportunities for government to engage with the private sector to create a modern and relevant SAPO. Classic examples in practice globally include Germany’s DHL (owned by Deutsche Post AG) and the UK’s Royal Mail (owned by International Distribution Services plc). Although both are privatised, they continue to serve their countries – and customers worldwide – with distinction. Imagine a SAPO that could follow suit, maybe even spreading its wings across Africa.

Public-private partnerships are a global trend As has been proven worldwide, private investors are the best placed to restore, renew and grow any sector because they understand the risk factors, and what – in their view – is bankable. However, this doesn’t mean that the state’s responsibility needs to be compromised in terms of oversight and essential service provision.

A prime example is government’s overall responsibility for the provision of national energy security, but with free rein given for independent power producers (IPPs) and municipal entities to bridge the infrastructure gap.

Everyone wins. Growing the IPP market creates employment and new, competitive skills.

FREE STATE & NORTHERN CAPE Secretary: Wilma Van Der Walt Tel: +27 (0)83 457 4362 Email: imesafsnc@imesa.org.za

The ABC logo is a valued stamp of measurement and trust. IMIESA is ABC audited and certified.

A recent example of a groundbreaking IPP initiative is the City of Cape Town’s announcement that it plans to develop a R1.2 billion solar PV plant with the potential to generate up to 60 MW, thanks to funding support from the C40 Cities Finance Facility.

Feasibility studies are expected to be completed towards the end of 2023, with plant commissioning planned for 2026.

In April, the City also put out a tender for 500 MW of additional capacity to be supplied by the rapidly growing Western Cape IPP segment.

Compliance and more compliance However, state funding for energy – driven by taxation and society’s needs – remains a dominant part of the equation, as it should, since enabling social and civil infrastructure is government’s primary mandate, with or without private support.

And there’s always a business model that must be followed. A case in point is the water and wastewater treatment segment, where the billable services rendered are vital for municipal service delivery – so it’s an enterprise in practice.

That’s why, going forward, all SOEs and allied public entities must run as financially sound businesses that don’t drain the tax base with wasteful expenditure. The upside is that the Auditor-General South Africa’s office is now empowered to intervene and pre-empt material irregularities that have resulted in too many unsatisfactory audit outcomes – ones that now threaten the outlook for entities like SAPO.

Alastair

IMESA

@infrastructure4

Infrastructure News

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

INFRASTRUC TURE DEVELOPMENT • SERVICE DELIVERY • ROADS • BUILDING • MAINTENANCE • ENERGY

Roads & Bridges New frontiers in digital engineering

Trenchless Technology Factors to consider when lining pipelines Stormwater & Drainage Sustainable attenuation ponds

Waste & Recycling Stemming the flow of e-waste to landfills

Novus Holdings is a Level 2 BBBEE Contributor: novus.holdings/sustainability/transformation

Cape Town solar plant

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. www.infrastructurenews.co.za

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. _____________________________________________

Furthermore, it helps ensure the current financial sustainability of key sectors like agriculture, construction, manufacturing and mining.

APE Pumps & Mather+Platt Success founded on passionate employees

Cover opportunity

In each issue, IMIESA offers advertisers the opportunity to get to the front of the line by placing a company, product or service on the front cover of the journal. Buying this position will afford the advertiser the cover story and maximum exposure. For more information on cover bookings, contact Joanne Lawrie on +27 (0)82 346 5338.

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IMIESA April 2023

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PRESIDENT’S COMMENT

IMESA

MUNICIPAL ENGINEERING IS A KEY ENABLER During April 2023, I had the oppor tunity to attend the first International Federation of Municipal Engineering (IFME) board meeting for the year, as the representative for South Africa and IFME’s other Southern African member countries, namely Botswana, Namibia and Zimbabwe.

H

osted in Birmingham, England, this coincided with the Interchange Conference focusing on integrated transport infrastructure, including how information technology, artificial intelligence and alternative energies like green hydrogen will shape the future of smart city mobility.

In parallel, as one of the Interchange’s six co-hosted events, was the 2023 IFME World Congress, where I had the opportunity to network and exchange ideas with my municipal engineering counterparts on shared experiences.

It’s refreshing to note that our Southern African challenges are not unique – particularly when it comes to asset management and optimum infrastructure utilisation. There were key speaker presentations in this respect from the UK and New Zealand, homing in on the

challenges of managing and detecting underground ser vices.

While non-revenue water (NRW) losses are a factor worldwide, the problem is particularly concerning in South Africa, due to our ageing and leaking infrastructure.

Estimates place this at around 35% on average, compared to a global benchmark of some 15%. In addition to lost billable revenues, the implications for our waterscarce countr y are severe and so far more needs to be done to monitor, maintain and upgrade pipeline ser vices, referencing best-in-class inter ventions.

Climate change is a real threat Climate change mitigation is crucial when it comes to extreme weather events, which includes the need for future-proof designs, ranging from river erosion control to stormwater management and sustainable urban drainage systems.

Lowering carbon emissions is an equal priority in terms of how we design and build structures, with an emphasis on using ‘green’ materials and techniques.

A key element will be the way renewable and alternative energies dovetail with current and future designs. Within this context, new fuels like green hydrogen will help to lower the cost in all sectors – from desalination to the powering of vehicles.

These and allied themes will continue to grow in importance as UN nations strive for net-zero emissions by 2050. They will also Sibusiso Mjwara, PrTechEng, MIMESA, MSAICE, MWISA, MIPET

be a major focus for the IFME 2024 World Congress scheduled for 23-26 September in Utrecht, Netherlands, under the theme ‘Future Green City.’ Utrecht is the ideal location, as this city is regarded as an international reference site for best-inclass municipal innovations.

Back in South Africa, we also need to do more to green our cities, and make them optimal living spaces, with a concerted effort made to promote a circular economy.

It is an exciting new frontier of exploration, and one that requires constant engagement between the public and private sector. Within this area, IMESA’s role is to facilitate positive change within the municipal space, constantly engaging with our Institute members, municipalities and industr y stakeholders to per fect workable solutions.

Strategic partnership A ver y encouraging development in this respect is that SALGA (South African Local Government Association) and IMESA are reviving the strategic par tnership agreement that was signed in 2011 to strengthen collaboration and assist municipalities with their infrastructure challenges. A steering committee is being appointed to identify which of the key issues can be addressed and to ensure that the proposed strategies are implemented.

Working together, we are stronger in our quest for a sustainable world that delivers dignified and enabling infrastructure ser vices.

IMIESA April 2023

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COVER STORY

Success founded on PASSIONATE EMPLOYEES Companies that consistently perform and deliver exceptional customer service in their niche markets have an infinite life. A prime example is the legendary history of APE Pumps and sister company Mather+Platt, which have been pump leaders in South Africa since 1952. General manager John Montgomery profiles some of the key men and women who continue to shape the group’s future.

B

eyond being an original equipment manufacturer (OEM), the group is graded as a 7 ME contractor in terms of the Construction Industry Development Board rating system, operating across South Africa, as well as in Southern Africa, with a permanent office in Lusaka trading as PSV Zambia.

“Since 1952, the group and its personnel have been involved in a wide variety of South African and African infrastructure and industrial projects, developing a rich legacy

6 IMIESA April 2023

of experience,” says Montgomery, adding that today the South African and Zambian arms form part of the global WPIL Limited group of companies, all focused on OEM pump solutions.

“Every member of the group is a highly valued team player who contributes to our collective success. We invest extensively in technology, training and personal development, backed by apprenticeship and mentorship programmes.

As a result, we have exceptionally high employee commitment levels, which is why

so many of our staff stay with us through to retirement,” Montgomery continues.

An employee with 50 years’ service Currently, Noman Kroukamp, aged 75, is the group’s longest serving employee, now working four days a week in the Inventory Department where he supports the Sales, Planning, Manufacturing and Construction divisions. He has never retired, and remains with the group because of their recognition of his lifelong knowledge, expertise and dedication, passing on the invaluable lessons learnt to young members coming through the ranks.

His journey as a much younger man began in 1973 when he joined what was then referred to as Amalgamated Power Engineering – then headquartered in Bedford, England, and subsequently trading independently today as APE Pumps in South Africa following a buyout.

Prior to that, he worked for International Combustion Africa as a pupil engineer, in the process completing his NTC 5 and NTD

studies in mechanical engineering, with a specific focus on pumps and heat engines.

“I’ve had a passion for pumps ever since, and it’s been an amazing experience seeing the group grow in brand strength, backed by concerted research and development (R&D).

From inception, custom designs were always part of our offering, along with our standard range. Every drawing is on record since 1952, enabling us to refurbish or remanufacture any one of our pump models for all industries,” says Kroukamp.

A series of acquisitions From the 1950s, APE in South Africa embarked on its own acquisition path, which included the revitalisation of the Mather+Platt series in 1954. The latter has a pedigree dating back to the UK’s First Industrial Revolution in the late 19th century.

Other subsequent acquisitions included the Sangus Engineering turbine pump range, and the Fairbanks Morse vertical turbine series, complementing APE and Mather+Platt’s horizontal, vertical, split and end suction pump series.

Some of the key horizontal split pump installations at the time included systems for the roll-out of Eskom’s greenfield Duvha and Hendrina power stations. Allied to this were installations for some of Johannesburg and Pretoria’s high-rise buildings.

Every member of the group is a highly valued team player who contributes to our collective success.”

Annemarie Prinsloo, finance manager

There were many other subsequent acquisitions, such as the Robuschi pump offering, focusing on the petrochemical market, which was subsequently unbundled from the group.

However, ensuing developments led to APE’s appointment as the agent for the Byron Jackson petrochemical pump range – and, more specifically, the API 610 pump. The group is now the only manufacturer in the world to produce this series following the original OEM’s demise.

“If anything, the group’s quality keeps getting better every year, with current mechanised and software solutions far surpassing the tools I had as a fledgling technician, but the principles of pump design and fluid transfer haven’t changed,” adds Kroukamp.

Quality assurance Each pump that the group produces can have up to 100 or more components that form its internal workings, particularly on multistage pumps. One missing item, and the integrity of the overall system can fail.

Making sure this doesn’t happen is a core part of Themba Dlamini’s responsibilities as a quality assurance specialist, and it’s based on

a solid track record of experience that dates back to 1985 when he joined the group in the main Stores Department. Over time, he received practical training in the machining workshop, and added to his skill set by attending courses in industrial marketing.

“As my exposure to the business grew, I wanted to understand more about how our products fit into the market segments that we serve, as well as how they match up against the competition. That has been key in performing my role,” says Dlamini.

Every pump manufactured, repaired or retrofitted by the group adheres to a sectional arrangement drawing produced by

Noman Kroukamp, Inventory Department

Themba Dlamini, QA specialist

Lyn Braybrooke, office manager and HR

Jamie Robinson, sales

Gabriel Ngozo, sales

Thorne Zurfluh, mechanical engineer

IMIESA April 2023

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COVER STORY

the Engineering Department, with all the parts preordered and ready. “We never assume because attention to detail is essential for guaranteed pump performance. That’s why we follow each prescribed assembly step as well as check – and double-check – that the correct procedure has been followed,” adds Dlamini.

Administration That level of attention to detail is universal throughout the group and is especially important in terms of company administration and human resource management. This area of responsibility falls under the scope of office manager, Lyn Braybrooke, who has been with the group since 2002, in the process earning Microsoft Certified Professional registration.

Working directly with Peter Robinson, group CEO, her roles extend to include the compilation of tenders in conjunction with the Sales and Engineering teams. She is also responsible for all inventory purchasing, as well as supporting the group’s Contracting Division from a project management perspective.

“Given our high manufacturing volumes, just-in-time delivery is the key to cost-effective production, liaising with our local foundries, suppliers and group companies globally to ensure that each pump is delivered and commissioned on time, and within budget,” says Braybrooke.

“Troubleshooting comes with the territory, as does proactive internal and external communication – everyone needs to be kept informed. Foremost, though, is that if management looks after staff, they’ll look after the customer,” Braybrooke adds.

Finance For any business, strict fiscal discipline and prudent expenditure are key to a successful

enterprise. In this respect, following the money is the responsibility of Annemarie Prinsloo, as the group’s finance manager, who joined the organisation in 1997.

“I’ve worked in various industry sectors, and each one has its own unique elements. This has also proven to be the case on my 26-year journey – and counting – with APE Pumps and Mather+Platt,” says Prinsloo.

“Where my role really makes a difference is in ensuring that every element of our multifaceted supply chain is fully serviced from a financial management perspective. We’re Proudly South African and are committed to supporting local content and allied enterprise initiatives,” she continues.

“Another key focus is continued mentorship and training, so that future leaders are empowered with accurate information to plan and budget for company expansion,” Prinsloo adds.

Sales excellence The responsibility for driving bottom-line performance needs everyone on board, says Jamie Robinson, who forms part of the Sales team, with a specific focus on the African territories where the group operates. Robinson joined the group in 2002.

“I’ve been exposed to all areas of the business, which has strengthened my ability to tailor solutions for our clients. In Africa, some of our most notable projects include a turnkey system upgrade for Malawi’s Blantyre Water Board, ongoing work for the Royal eSwatini Sugar Corporation, and the supply of dewatering solutions for Zambian mining operations,” says Robinson.

Within the Sales Department – and working alongside Robinson – Gabriel Ngozo is one of the veterans, and has been honing his skills since

joining the group in 1984. That equates to close to 40 years of experience, which began when he joined as a receiving clerk, subsequently moving up to sales.

“One thing I can say is that ensuring the highest level of customer satisfaction has always been a top priority. We pride ourselves on manufacturing world-class products, and in ensuring long-term support. Matching the right pump to the application is vital, and I’ve gained extensive knowledge in this area,” says Ngozo.

“Then, from an aftersales perspective, we have a detailed record of every pump we’ve ever sold, installed and commissioned, along with all the serial numbers for every component, so, when it comes to a rebuild or replacement, the parts are always available,” adds Ngozo.

Engineering Maintaining product leadership is crucial, and that hinges on ongoing R&D, investments in modern machinery, as well as embracing new 3D design and software simulation tools.

For mechanical engineer Thorne Zurfluh, it’s an exceptional opportunity to perfect pump selection designs and to interface with the client’s engineers when the group implements turnkey projects. He joined the group in June 2022 having worked previously as a design engineer with an EPCM contractor.

“Pumps have always fascinated me and I’m very excited about working with an organisation that has such a long and proud legacy. Fluid transfer processes are essential for all industries, as well as the delivery of water and wastewater services; in this respect, the group is a pioneer in terms of innovation,” he explains.

Adds Zurfluh: “Future designs will be driven by the need for improved energy efficiency, as well as enhanced maintainability and serviceability.

We’re also seeing an increasing shift towards outsourced operations and maintenance, which is a key growth area for the group, working with clients to optimise their systems.”

Teamwork makes the dream work For Montgomery, who has served 20 years with the group, it’s a privilege to head up such a dedicated and talented team.

“We didn’t become a pump leader and masters of fluid control by chance. Our growth over more than seven decades has been driven by engineering excellence and world-class customer service. Achieving that has only been possible because of our exceptional people,” Montgomery concludes.

www.apepumps.co.za www.matherandplatt.com

8 IMIESA April 2023

BIENNIAL PROJECT EXCELLENCE AWARDS

CALL FOR ENTRIES To recognise outstanding achievements in municipal infrastructure, we are calling for entries

Planning and design Construction methods Innovation and originality

that showcase projects that demonstrate the best of civil engineering as a science and how engineering

Meeting social and technical challenges

enhances the lives of the local communities, through excellence in:

Contributing to the well-being of communities

CATEGORIES

1

ENGINEERING EXCELLENCE IN STRUCTURES & CIVILS E.g. Projects demonstrating engineering science, use of alternate materials, innovative construction processes, etc.

2

COMMUNITY UPLIFTMENT & JOB CREATION E.g. Projects demonstrating labour-intensive construction, skills development, community awareness/participation, etc.

3

ENVIRONMENT & CLIMATE CHANGE E.g. Environmental rehabilitation, renewable energy, drought solutions, coastal initiatives for rising sea levels, pollution control, educational/ technical initiatives, etc.

CLOSING DATE FOR SUBMISSIONS 03 July 2023

Only projects that have reached practical or substantive completion by 30 June 2023 will be accepted for the Excellence Awards.

Adjudicators reserve the right to reallocate entries in the 3 categories.

ENTRY FORMS AND AWARD CRITERIA Available for download on the website: www.imesa.org.za

IMESA THE INSTITUTE OF MUNICIPAL ENGINEERING OF SOUTHERN AFRICA (IMESA)

QUESTIONS Contact Debbie Anderson on +27 (0)31 266 3263 or email conference@imesa.org.za

INFRASTRUCTURE NEWS

FROM AROUND THE CONTINENT

MOZAMBIQUE LNG production set to expand Exxon Mobil is calling for expressions of interest in the design and building of a liquified natural gas (LNG) plant. To be situated in the north of Mozambique at the Rovuma Basin, the plant is set to have a capacity of up to 18 million tonnes a year.

Exxon’s announcement comes after TotalEnergies SE released a statement where it is considering restarting its own LNG export venture Mozambique’s Cabo Delgado province. Both Exxon’s previous project and TotalEnergies’ project were halted two years ago following an attack on the town of Palma, but a mix of local and foreign troops have since made progress in containing the violence that’s left more than 4 600 people dead.

In its new project, Exxon Mobil is reportedly partnering with the China National Petroleum Corporation, Portugal’s Galp, South Korea’s Kogas and Mozambique ENH. Exxon is part of a consortium with Eni SpA of Italy, which in November exported Mozambique’s first LNG production from a floating vessel offshore. That plant has an annual capacity of 3.4 million tonnes.

EGYPT Third nuclear reactor to be built The Egyptian Nuclear and Radiological Regulatory Authority (ENRRA) has issued the construction licence for the third reactor (Unit 3) of the country’s four-reactor nuclear power plant (NPP) at El Dabaa. Egypt currently operates one 22 MWt capacity research reactor.

El Dabaa will be the country’s first NPP and is located on the Mediterranean coast, some 320 km north-west of Cairo. El Dabaa is being developed and will be operated by the country’s Nuclear Power Plant Authority (NPPA). Its reactors will be to the Russian state-owned nuclear energy group Rosatom’s VVER-1200 design, already in use at Russia’s Leningrad and Novovoronezh NPPs and at Belarus’ Ostrovets NPP. The Dabaa plant is part of a deal signed in 2015 between Rosatom and Egypt, which is expected to cost about US$30 billion (R545 billion).

Construction of Unit 3 is expected to start within the next few months. Construction of Unit 1 commenced last July, while that of Unit 2 started in November. The NPPA applied for the construction licences for both Unit 1 and Unit 2 in June 2021, while its applications for the same licences for both Unit 3 and Unit 4 were submitted in January last year.

Once the construction permit has been issued, the technical works for the first concrete of the third nuclear unit are intended to commence during the second quarter of this year.

10 IMIESA April 2023

MALAWI Grant to boost Blantyre water and sanitation The International Development Association, a World Bank subsidiary, is set to provide a US$145 million (R2.6 billion) grant to Malawi’s Blantyre Water Board (BWB). The utility will use the funding to increase access to safe water and sanitation for approximately 500 000 people in the city of Blantyre.

New water supply facilities will be built and independent power sources will be added so that facilities can operate during power outages. Drinking water and sewage systems will also be upgraded for greater efficiency, as will solid waste management facilities.

According to the World Bank, the project will last six years. In addition to water and sanitation safety, the project will enhance the operational and financial efficiency of the BWB, whose mission is to provide reliable and affordable water services to Malawians, while contributing to the development of the national economy and preservation of the environment.

TRENCHLESS TECHNOLOGY | SEWER REHABILITATION COVER STORY

MOROCCO Electric trucks for waste management

KENYA $2.4 billion worth of dams to boost water availability Kenya plans to seek investors to help build seven dams at a cost of US$2.4 billion (R43.6 billion).

The government plans to sign water-purchase agreements with investors who will finance, design, build and commission the facilities. The mechanism will enable investors to sell and deliver water needed for household and irrigation use.

The biggest planned water project is the High Grand Falls Dam on the Tana River, in eastern Kenya, with a capacity of 5.6 trillion litres that is expected to cost $1.3 billion (R23.6 billion).

President William Ruto, who came to office in September, has pledged to develop at least 100 dams to improve water security and boost agricultural productivity. Several amendments are planned to the East African nation’s Water Act to provide a framework for the government to buy water in bulk from investors for resale to public water companies that supply homes and farms that irrigate fields.

Kenya plans to put 375 864 ha under irrigation and connect 4.25 million new households to clean piped water.

Refuse collection company Armahas recently taken deliver y of Volvo Trucks’ first heavy batter y-electric truck.

“This is a proud moment when we take the first step to more sustainable, electric transpor t in Morocco and Africa together with our customer Arma and the city of Rabat. This clearly shows that zero-emissions trucks have a role to play in many par ts of the world.

Volvo is the first global brand with heavy electric trucks in commercial operation in Africa. We have the broadest electric truck line up in the industr y, which makes it possible to electrify a large par t of heavy transpor ts already today,” says Mar tin Nilsson, MD, Volvo Trucks Morocco.

By replacing the existing Volvo FE diesel truck with a Volvo FE electric on a typical route, approximately 30 tonnes of CO2 could be saved ever y year.

Morocco has ambitious climate goals, based on large investments in renewable energy. The countr y is a leader in solar power and home to the world’s biggest concentrated solar power facility, Noor Quarzazate, located 200 km south-east of Marrakech.

TANZANIA Funding for Kakono hydropower plant A signing ceremony has been held for funding agreements with the African Development Bank (AfDB) and Agence Française de Développement (AFD) for financing of the 87.8 MW Kakono hydropower plant. A fur ther €36 million (R718 million) will be provided by the European Union for technical assistance, environmental studies and capacity building.

Cedric Merel, head of cooperation with the EU delegation, said the EU is glad to contribute to effor ts by the government of Tanzania to diversify its energy sources and bring green energy into the mix. He said the Kakono project also will reduce greenhouse gas emissions by 213 810 tonnes per year, making a significant contribution to economic development and climate change adaptation.

The Kakono Dam will be in the Kagera Region in the nor th-western corner of Tanzania, near the border with Uganda, about 90 km west of Bukoba Municipality. It will be located on the Kagera River and owned/operated by the Tanzania Electric Supply Company Limited (Tanesco).

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THOUGHT LEADERSHIP

PPC’s strength and vision

supports African infrastructure expansion South Africa’s construction sector is under major pressure to sustain itself, but there are positive signs of an upward trend. Alastair Currie speaks to Bheki Mthembu, executive, PPC, about how the group’s operations are faring locally and in Africa.

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PPC runs CETA-accredited training programmes for communities covering all the steps required to build a house using its products. Skills include construction management, bricklaying and plastering

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What is PPC’s take on opportunities for the civils and building sectors in 2023?

BM The approximately R903 billion allocated by the South African government for public sector infrastructure investments over the next three financial years starting in 2023/24 is very encouraging. As we understand it, there are four provinces where the bulk of the funds will be

Bheki Mthembu, head: Inland Business Unit at PPC

12 IMIESA April 2023

allocated, namely Gauteng, KwaZulu-Natal, and the Eastern and Western Cape.

Historically, there have been funding constraints and implementation bottlenecks; but if we can effectively unlock elements of this investment pipeline, it will have a highly positive impact on our construction and broader macro economy. It is well known that we have an extensive infrastructure backlog in terms of energy, housing, rail, roads, water and sanitation, so the time for action is now.

As South Africa’s largest cement producer, PPC is well positioned and invested to support demand in the local market, backed by a comprehensive national distribution network stretching from Cape Town to Musina.

Internationally, we also have operations in Botswana, Zimbabwe, the DRC and Rwanda.

Our products have been tried and tested over the past 130 years of our existence and, during that time, have been an integral ingredient in a large portion of South Africa’s existing infrastructure, including megaprojects like Gautrain. That is also certain to be the case going forward.

Our slogan – ‘Strength and beyond’ – underscores our commitment to a life-long journey with our customers in terms of product excellence, custom solutions and comprehensive technical support to meet

specific project specifications. These services are backed by our state-of-the-art laboratory testing facilities housed at our Jupiter plant in Gauteng.

Together with all of these elements, however, the one crucial thing we need to get right is public and private sector alignment and collaboration. The best infrastructure master plans – including the National Infrastructure Plan 2050 – are only possible if there’s a strong and sustainable construction industry to execute them. Plus, we need to educate and empower our communities to realise the benefits of social infrastructure as an enabler for education, healthcare and employment.

How does the African regional construction economy compare with trading conditions in South Africa?

Currently, in other countries where we operate in Africa, most are reflecting positive GDP growth, plus there’s a high level of public accountability and willingness to get things done.

Rwanda is experiencing a construction boom with landmark projects underway that include the Bugesera International Airport, situated approximately 25 km south-east of Kigali, where PPC is supplying bulk cement.

The road and bridge segments are also very active in Rwanda – both for new construction

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and maintenance – as is the residential housing market.

Due to the strategic location of our Rwanda plant, we’re also seeing a surge in bulk cement export demand into neighbouring countries like the DRC. Meanwhile, in Zimbabwe, the country is currently investing 5-7% of GDP on public infrastructure projects that include dams, housing, roads and solar power plants. Over the past eight years or so, the housing market in particular has created huge demand for bagged cement, and this trend is set to continue.

In terms of megaprojects, the Gwayi-Shangani Dam development stands out as a significant one. The dam has an estimated reservoir capacity of some 634 million m3 and is now at an advanced stage of construction. Then on the roads side, there’s the Beitbridge-Harare Chirundu Highway project, which is one of Zimbabwe’s largest transportation investments in decades.

In Botswana, we also expect to see a renewed investment in infrastructure in areas like water and sanitation, schools and gravel-to-asphalt road upgrades within towns and settlements.

But back in South Africa, the pace has been slower than in our other territories; however,

as I mentioned in the beginning, the pipeline is growing.

How is PPC helping to make a difference for contractors and communities?

Alongside our technical services for construction projects, PPC invests extensively in community training in the regions in which it operates. We definitely support the view that no one should be left behind.

Examples include our CETA-accredited training on the steps required to build a house using our products. Skills include construction management, bricklaying and plastering. We trained around 200 people in South Africa during the past financial year through the CETAaccredited programme. However, we believe this programme is invaluable for aspiring SMMEs everywhere, as well as unemployed persons seeking entry into the building industry.

Allied to this, we’ve trained about 4 000 brickmakers nationally through our brickmaking workshops. The training focus is on making a quality brick and the business side of running a brickyard.

Alongside our own internal graduate and allied artisan development initiatives, we also run apprenticeship programmes for external candidates who may subsequently

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THOUGHT LEADERSHIP

How have sustained Eskom power outages affected PPC’s production in SA?

PPC’s commitment to its communities begins at the early childhood development stage, where its ‘Build a Word’ board game promotes the importance of reading for comprehension as the foundation for life

be offered a position with PPC. Trades include fitters and turners, and boilermakers.

Foremost, though, is our appreciation that the building blocks for education and skills development start at preschool and primary school level. In response, we fund projects that include meals programmes, the building and refurbishment of schools, as well as the distribution of our ‘Build a Word’ educational board game kits that promote spelling, reading comprehension and writing.

Recent CSI outreach examples include a new creche facility for Redeemed Kids Kingdom Preschool in Daveyton, Gauteng.

PPC also recently ‘adopted’ the Happy Sabby Day Care Centre in Gomora, close to the group’s Hercules plant in Pretoria.

Are cement import volumes into South Africa dropping off or increasing?

Currently, the entire South African cement producing industry has an estimated spare capacity well in excess of 35%. For this reason, there’s absolutely no justification for cement imports, but there’s still evidence of this. Estimations put this at around 1 million tonnes annually.

As a proudly South African company, PPC, like other local producers and companies in the cement logistics supply chain, is committed to transformation, SLP and CSI contributions, pays tax, and directly and indirectly creates employment. Cement imports do not contribute and may in fact not meet our strict quality standards, which has implications for potential structural failures.

14 IMIESA April 2023

The upside is that there has been an estimated 20% decline in imports, but this could partly be due to the recent slide in the rand against the US dollar, which makes it less attractive to import. But the threat remains when market conditions become more favourable.

What needs to change in South Africa to accelerate our economic reconstruction programmes?

For investors, policy certainty is essential, as are an enabling environment and legal enforcement, especially when it comes to procurement and stakeholder engagement.

A case in point is the so called ‘construction mafia’. We really need to get on top of this phenomenon, as it is a major downside risk, deterring investments and delaying projects along with the knock-on effect of cost overruns. It’s also not something we see happening in other parts of Africa where we operate.

We have a dedicated supply agreement with Eskom as a heavy industrial user, so in principle we should not be affected. However, at times we’re requested to curtail demand on the grid during higher load-shedding stages.

This means that we need to shutdown powerhungry units – sometimes for up to six hours – which has serious implications for our production on specific products. Sometimes, to meet an order, we’re also forced to operate during peak periods where the Eskom tariff is the highest, which significantly increases our manufacturing cost.

Then there are the power dips and subsequent surges that burn out critical equipment. So, load-shedding ripples across the value chain – from our mining operations to the factory and dispatch.

But clearly, we don’t function in isolation.

The impact of load-shedding across society and business in general has been devastating. So, before we talk infrastructure development, we need to guarantee energy security and keep it affordable. In the meantime, we are rolling out solar solutions across our operations to reduce the baseload demand wherever practical.

And in closing?

As a manufacturer, we live by our brand promise of empowering people to experience a better quality of life. We are integral to South Africa’s future, as well as the other African countries where we operate.

The potential for positive socio-economic gains within the sub-Saharan region are significant, and we need to leverage the opportunities together through stronger public and private engagement.

ENERGY & ELECTRIFICATION

Testbed investment in battery storage technology

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he CSIR’s newly established indoor energy storage testbed facility will support the continued roll-out of battery technology developments in the South African market. Its establishment forms part of a collaboration agreement between the CSIR and VITO (the Flemish Institute for Technological Research), within the framework of the World Bank Energy Storage Partnership initiative.

“The facility will provide much-needed testing for the country. It will be used as a service for technology developers or importers who would like to characterise their technologies for market entry. Additionally, it is a stepping stone towards addressing the intermittency challenge of renewable energy,” says Renesh Thakoordeen, project leader: Energy Storage Testbed, CSIR. In addition to being equipped with a high-precision system for battery module and pack tests, the facility also features a new-generation temperature chamber to provide data on the operating behaviour of batteries used in harsh climates.

Carlo Mol, project manager: Energy Technology, VITO, says the energy storage testbed is the first step towards a broader cooperation between the CSIR and VITO. This follows the signing of a memorandum of understanding in April 2022 to extend their research to cover a broad range of sustainable technologies.

The CSIR’s Ranesh Thakoordeen (left), researcher and project lead, and Sumi Moodaliyar, researcher, at the indoor energy storage testbed facility

Zutari achieved a 6 Star Green Star rating and WELL certification for the Exxaro head office in Centurion

MORE TIME TO PREPARE FOR EPC COMPLIANCE

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roperty owners and inspection bodies have been given much needed breathing room thanks to an extension of the deadline for energy performance certificates (EPCs) for buildings. The Department of Mineral Resources and Energy announced the three-year extension to 7 December 2025 on 25 November last year.

The difference between the current Green Star energy performance rating system from the Green Building Council South Africa (GBCSA) and EPCs is that the former is voluntary while the latter will become mandatory, explains Martin Smith, design director and expertise leader: Building Services at Zutari.

In terms of the regulations, EPCs will need to be in place for public and private buildings over 1 000 m2 and 2 000 m2, respectively.

Zutari is a well-established market leader in this niche sector and has already certified over a hundred Green Star projects in accordance with GBCSA’s criteria. One of the most notable is a 6 Star Green Star rating for Growthpoint Properties’ flagship Exxaro head office development in Centurion. This was also the first building in South Africa to achieve WELL certification by the International WELL Building Institute.

Real-time tracking To hone its market offering going forward, Zutari has partnered with 4Sight, a leader in digital transformation, to implement a sustainable data strategy. Among other things, this will enable near real-time tracking of building performance.

The combination of 4Sight’s domain expertise in digital transformation and Zutari’s scientific and engineering knowledge creates a unique value proposition to help customers maximise the value of their assets, particularly in terms of optimising energy and water use – ultimately reducing their carbon footprints. For applicable building categories, this will also aid in EPC compliance.

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URBAN DEVELOPMENT & RENEWAL

of managing capital YEARS expenditure projects The Johannesburg Development Agency (JDA) turned 22 on Saturday, 1 April 2023 and looks forward to working even harder to implement infrastructure developments – one of the most capitalintensive areas of municipal spending.

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he JDA plays a role in the implementation of the Growth and Development Strategy of the City that responds to the Joburg 2040 ideals of resilience, liveability and sustainability.

Established in 2001, at a critical moment in Johannesburg’s history as part of the iGoli 2002 re-engineering process, the JDA now celebrates more than two decades of managing capital expenditure projects. Below are a few project milestones reached in year 21 of its operations.

Year 21 milestones Gandhi Square East public environment upgrade: In Gandhi Square East, the JDA Orchards Clinic

16 IMIESA April 2023

completed the Main Street Public Environment Upgrade, turning the area into a high-quality environment and enhancing the pedestrian experience, featuring wider sidewalks, pedestrian lighting, landscape, trees and

Oval Park and Bertha Solomon Recreation Centre

natural elements, and upgraded Portplein Park as part of the scope of works.

Drieziek public transport facility: The allweather, aesthetically pleasing Drieziek public transport facility includes 37 holding bays, 42 loading bays, 10 wash bays, private car parking, 22 trader stalls, ablution facilities and a public square for traders with a sitting area.

Opened on 10 December 2022, the public can now enjoy this amazing facility and travel to their destinations safely.

Orchards Clinic: Opened by Gauteng Health Department in September 2022, Orchards Clinic is a vibrant, primary healthcare facility with 20 consulting rooms, emergency rooms, antenatal, ARV and TB service facilities, a courtyard, office space and a parking area for staff and patients.

URBAN DEVELOPMENT & RENEWAL

Oval Park and Bertha Solomon Recreation Centre: As part of the Eastern Gateway Precinct master plan, JDA completed the construction and upgrade of the Oval Park and Bertha Solomon Recreation Centre. The JDA engaged residents and other park users to design a safe, accessible, inclusive and sustainable public space through participatory tools and methods. The project received a certificate of recognition for excellence at the Institute for Landscape Architecture in South Africa’s 2022 Awards of Excellence.

Lenasia public transport facility: The Lenasia public transport facility opened to the public in December 2022. The project forms part of the JDA’s turnkey projects identified for upgrades. The intention of the upgrades was to accommodate taxis, traders, pedestrians and commuters in a safe, clean and attractive environment that will enhance the overall functionality of the Lenasia CBD.

CEO on JDA’s future development interventions Speaking about the JDA’s longevity and success, CEO Mokgema Mongane explains that there are two fundamental management approaches in the universe – the task-based approach, and the people-based approach.

“I believe in a delicate balance of longevity, resilience, tenacity and sustained success.”

The JDA plays a pivotal in taking Johannesburg forward and it is Mongane’s goal to fine-tune and optimise the delivery

of infrastructure and development projects more efficiently.

“Essentially, the JDA plays a key role of providing infrastructure development on behalf of numerous client departments and other municipal entities within the City of Johannesburg. These include the Department of Development Planning, Human Settlements, Health, Public Safety, Transport, Community Development, Social Development, and the Johannesburg Roads Agency,” Mongane notes.

“The infrastructure projects comprise transport-oriented developments, public environment upgrades, stormwater and gravel road upgrades, clinics, fire stations, public transport facilities, bus rapid transit Lenasia Public Transport Facility

Drieziek Public Transport Facility

infrastructure, multipurpose centres, libraries and shelter,” he adds.

When asked what he will be prioritising over the next year to ensure the success of the projects by the JDA, Mongane explains that the entity’s immediate focus revolves around its financial sustainability and initiatives.

These include revenue enhancement activities within the short- to long-term ranges.

Looking ahead to the next five years, Mongane’s long-term goals for the JDA are: Operational efficiency: focusing on continuous improvement/optimisation of core business processes and delivering projects on time, within schedule and as per specified quality.

Capacity creation: to capacitate the organisation in terms of human resources, technology and tools of trade.

Revenue enhancement: to generate sufficient revenue for financial sustainability in the long run as well as expand on and optimise the client base.

“As we reach our 22-year milestone, we acknowledge that without our committed Board, Management and Employees, this will be an impossible task, and we know that it is the people at the JDA who make the JDA. We look ahead to greater heights,” Mongane concluded.

www.jda.org.za

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WASTE & RECYCLING

Stemming the flow of e-waste to landfills and extracting sustainable value In terms of the legislation, waste from electrical and electronic equipment – widely termed e-waste – can no longer be sent to a landfill for disposal and needs to be recycled. Alastair Currie speaks to Keith Anderson, CEO of eWASA, about the body’s role as a Producer Responsibility Organisation (PRO) in managing the process, which includes interacting with municipalities.

What are some of the key developments leading up to eWASA’s registration as a PRO?

Department of Forestry, Fisheries and the Environment (DFFE) gazetted the new Extended Producer Responsibility (EPR) regulations, KA In March 2021, the Minister of the which came into effect on 5 November 2021, with wide-sweeping implications and obligations for not just manufacturers of electrical and electronic equipment – but also distributors, retailers and wholesalers – to take back and recycle all types of end-of-life products. There was a six-month window to enable industry to make preparations.

Prior to this, a great deal of public and Keith Anderson, private stakeholder CEO of eWASA engagement had taken place over a period of years in negotiating the finalisation of an Industry Waste Management Plan for ours and other sectors in accordance with a Section 28 Notice issued in terms of the National Environmental Management: Waste Act (No. 59 of 2008).

Then, in 2020, the Minister announced the withdrawal of Section 28 and replaced it with the Section 18 EPR

18 IMIESA April 2023

regulations. This went out for public comment, which led to the establishment of a Ministerial Task Team to iron out issues raised, on which I served as one of the advisory members as an e-waste industry representative. eWASA was subsequently appointed as a PRO to manage EPR responsibilities in our sector, which in our case encompasses electrical and electronic equipment, lighting, paper and packaging. Just to clarify, there are other PROs in these fields, each with their own action plan.

Our overall mandate as eWASA is to ensure that e-waste, which falls into the hazardous waste category, does not pose a risk to the environment. Plus, there are major commercial opportunities, and we support government’s objectives to create employment and grow SMMEs in the recycling sector.

What progress has been made on EPR implementation?

From a PRO perspective, we’ve scaled up our capacity to manage the process. This includes advising our members on the steps required across the full value chain, from producers to dismantlers, refurbishers and waste pickers.

A key portion of the latter focus is on the packaging sector, collecting plastics, but there are a smaller number also collecting e-waste.

In terms of the regulations, the PRO and producers are required to negotiate with the waste pickers and establish a collection payment scale. We have engaged with the South African Waste Pickers Association and the Association of Recyclers, as the two main representative bodies in the country, and are close to finalising an agreement. Part of the requirement is that all waste pickers will need to be registered. That’s beneficial in terms

WASTE & RECYCLING

back in payment to certified recyclers who treat e-waste responsibly.

Are municipal landfills complying?

of knowing the numbers, plus it’s part of formalising the sector.

Another positive development is that every registered recycler will be able to claim back from the PRO for products recycled. An example could be a recycled product originally produced by a leading electronics manufacturer registered with eWASA. The recycler will be required to submit a materials recovery sheet to claim a refund.

Has the e-waste industry complied?

Yes and no. We have some exceptional examples of good corporate citizenship, where producers manufacture their products with life-cycle reutilisation as the starting point, and with passionate support for the EPR mandate. Generally, though, the response from producers has been mixed.

For producers, there are added cost implications since they now need to register with eWASA, or another sector PRO, and pay EPR fees to have their end-of-life products collected and disposed of in an environmentally sound manner. However, we still have a situation where a high percentage of producers are not on board in terms of the regulations.

This ‘free rider’ situation is unacceptable, as it unfairly prejudices paying members, many of whom are global manufacturers that currently pay millions in EPR fees.

The world’s best legislation is meaningless if it’s not enforced.

So, from eWASA’s perspective – as a pioneer in promoting e-waste – we believe there needs to be more proactive enforcement by the DFFE. From our discussions, the department has indicated that it is scaling up its compliance division, but to date – to the

best of our knowledge – no one has been prosecuted for non-compliance.

The regulations make it clear. Fines can go up to R5 million and/or a 15-year prison sentence.

How is the PRO funded?

By September 2021, all PROs had to submit their EPR fee methodology for review by the Minister of the DFFE, followed by a final vetting process by the Minister of Finance and the issuing of a concurrence letter. We received our letter in July 2022. That put us a bit on the backfoot, but we are now moving forward with good traction.

Our current PRO plan approved by the DFFE runs for five years. In terms of the agreement, a portion of the EPR fees can be used to sustain the PRO on a progressively declining scale. In year one, which was 2022, it was a maximum of 20%. This year, it’s 15%, and from year three onwards 12%. The upside is that this encourages prudent expenditure. The downside is that for smaller PROs, it may not be financially sustainable longer term.

From eWASA’s perspective, each producer provides us with a five-year forecast and we have excellent industry support. Some 70% of the funds paid by producers are ploughed

Before I answer that, let’s ask the question: “Are domestic households currently separating their hazardous waste at source?”

The answer in many cases is no. And even where responsible citizens do separate at source, how many municipalities are equipped to collect and treat hazardous waste in terms of engineered disposal sites?

Against this background, the DFFE’s recent release of the draft Household Hazardous Waste Management Strategy for public comment prepares the groundwork. It will also clarify the gaps between EPR obligations and municipal landfill responsibilities.

As a PRO, we are required in accordance with the regulations to form relationships with municipalities. The feedback we often receive is that they have insufficient funding, expertise and capacity, so industry must manage the problem. That’s clearly not practical. As in regions like Europe, e-waste needs an organised and systematic framework, and the central facilitator is the public sector. We need distinct colour-coded bags and collection bins for each designated waste stream. eWASA’s response is that we can assist municipalities with technical advice on establishing disposal sites, and we can put them in touch with our certified recyclers.

Plus, there’s a very willing waste picker segment that can be mobilised.

As part of the eWASA Foundation, we plan to roll out a series of online and in-person training programmes aimed at stimulating SMME development. We also plan to reach out to schools to educate children about e-waste, as well as install collection bins at these facilities. A portion of the funds from the recycled waste will be donated back to the schools.

And in closing?

E-waste recycling is a highly lucrative industry globally, and there are niche players in South Africa who are showing the way. Foremost though, it’s an environmental imperative and we must ensure compliance with the legislation – whether from imports or locally produced goods – and prevent e-waste going to landfill. From a PRO standpoint, our producers are committed to the process, but we need everyone on board, including the municipalities, to make it work.

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CONTRACTS & INTELLECTUAL PROPERTY

In today’s world, we often hear about corruption, theft and extortion in various fields. However, when it comes to using the procurement process as the basis for theft and extortion, it is nothing less than a criminal act.

Unfortunately, it is a practice that is rampant in South Africa.

By Burgert Gildenhuys*

Procurement as the basis for theft and extortion

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t is no secret that South Africa pays lip service to small businesses’ development and innovation, but its deeds speak the opposite. The government’s approach through the tender conditions it introduces regarding intellectual property is a prime example of how corruption gets institutionalised in the country.

One of the ways this happens is by forcing professional service providers to surrender all claims to intellectual property and/or copyright in terms of any systems, methodologies, processes developed or data collected/ improved under a contract. This practice is not only unethical, but it also goes against the principles of fair competition and innovation.

Furthermore, it is a form of extortion, where the service provider is forced to give up their intellectual property in exchange for the contract.

Terms of reference When a ‘terms of reference’ states that all data collected or derived from work during the contract period is retained and belongs to the client, the project becomes a way of accessing data without paying for it. Most often, the data used in a project belongs to third parties and access to it is governed through specific agreements. What belongs to the client are the deliverables and not the data, tools and means to produce what is required. It is a form of theft where the government tries to expropriate

20 IMIESA April 2023

property without compensation. This practice is unacceptable and needs to be condemned in the strongest words.

Even suggesting that the data collected or derived must be provided to the client and its agents in a prescribed format free of cost and compensation is highly unethical, and, again, if a contract requires free handouts, it is simply extortion. Every planning study starts with a data collection phase. However, we are not aware of a single tender that is prepared to acknowledge the cost of data in the pricing of a tender, but every single tender demands, as a condition of tender, that data must be handed over free of charge, cost or compensation.

What is the difference between this and some official or politician demanding payment for awarding a tender? If the latter happens, everyone will cry corruption, but nobody blinks an eye when expropriating the service provider’s data, tools and means to produce what is required as a condition for awarding a tender.

Fair competition Developing systems and processes takes years, and millions are invested. Moreover, these systems and processes provide businesses with a competitive edge in pricing and delivery of services. This procurement practice is the most significant disincentive to innovation and a way for the government to strip a business of its competitive advantage.

The usual clause that excludes intellectual property registered before the bid dates is not enough protection for the service provider. These clauses are vague and open to interpretation, which could lead to the government taking away the intellectual property rights of service providers even for work done before the bid dates.

Furthermore, the fact that bids state that no proprietary systems or non-accessible software (read software to be paid for) will be accepted as part of a project reflects a lack of understanding or experience from the clients and procurement institutions. Recognising that

Burgert Gildenhuys, director, BC Gildenhuys & Associates

CONTRACTS & INTELLECTUAL PROPERTY

systems are essential for solving complex problems and driving progress is crucial.

Increased complexity requires sophisticated systems to manage and analyse data efficiently and accurately. Moreover, by preventing service providers from creating proprietary systems or non-accessible (read ‘not free’) software, one risks limiting a service provider’s ability to develop cutting-edge technologies that can help solve complex problems. One must recognise the value of intellectual property and the need to protect it.

Skills and capacity Skills transfer and capacity building are entrenched requirements in government tenders, and accompany the required data and systems. It alludes to the fact that officials must be fully empowered to use and apply the tools and systems developed as part of a project. However, this should not come at the cost of the service provider’s intellectual property rights.

The extent to which skills and capacity were destroyed in government is well documented. In addition, skills and experience take time and come at a considerable cost.

Twenty years of experience cannot be gained in a week or two. Transferring this

responsibility to a service provider is unfair and, when it is further incumbent on service providers to skill people in using their own products that have been unjustly extorted or expropriated, it can hardly be ethical or fair.

entrench the corruption culture further and institutionalise it in the country. It is time for South Africa to change its approach towards these procurement elements and adopt a fairer and more ethical approach.

Compensation

Recommendations

The government should compensate the service provider for their intellectual property and data collected during the project, and they should not force them to give it up. The practice of using procurement as the basis for horse trading and extortion is not only unethical, but it also stifles innovation and fair competition. Furthermore, it helps to

If we turn the focus and accept the bona fides of government in its approach and that extortion and expropriation of intellectual property are not the intention, then one needs to view it in the light of the government not having the resources to access what it needs and that it admits to skills shortages.

Then the right move will be to approach service providers who developed the systems and have the data required data or access to the data and sit down and devise a way to work around these barriers. One is unaware of a single service provider that will turn away the government when being approached for support. However, such support comes at a cost, and somebody – whether it is government itself, the service provider as an act of self-sacrifice or a benevolent third party – will have to pay. In the final analysis, leveraging tenders and contracts to access intellectual property, systems and data remains as unethical as can be. *Pr. Pln, MIAM (London), ILGM, B(TRP), BAdmin (Municipal Administration)

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ROAD CONSTRUCTION | TECHNOLOGIES, STANDARDS & SPECIFICATIONS

When it comes to quality,

durability and sustainability are interlinked it. Therefore, substandard products will be extremely detrimental in terms of strength and durability performance. The knockon effect is premature failure and more frequent maintenance, which all result in additional costs.

Non-compliance with material specifications is not the only concern though. From our experience, these types of operations do not have the necessary health and safety protocols in place, which poses a major risk to the people employed there.

Roadstab is a specially engineered, composite, high-quality cement that serves as a highly effective layer works stabiliser

Does the right cement make a difference?

South Africa’s future depends on world-class infrastructure and roads are the socio-economic conduit. IMIESA speaks to Amit Dawneerangen, GM Sales and Product Technical: AfriSam Construction Materials, about the group’s integral role as a leading construction materials supplier.

How does AfriSam add value?

So, it’s an exact science?

AD Working closely with contractors in the road construction space, we provide a turnkey package in terms of project-specific aggregate, cement and readymix solutions for road, bridge, and ancillary infrastructure such as culverts and pavements. On top of that, we’re able to produce customised products to meet the requirements of any project specification.

Additionally, every AfriSam product is supported by our Centre for Product Excellence (CPE), which includes in-field technical support.

Throughout, quality control is paramount.

Yes, it is. For example, by actively mapping quarry rock type and quality, AfriSam technical experts ensure that blasted material is expertly paired with the design engineers’ requirements in terms of specific grading, shape and wearing properties. For optimum performance, it’s crucial that the layer works materials have the necessary interlocking support, whether it’s a low- or high-volume road.

In this respect, AfriSam offers a range of specialty aggregate for layer works and asphalt designs. This includes aggregates for the base and pavement (G1-G3), as well as sub-base layers (G4-G7).

How serious is the threat posed by non-licensed aggregate quarries?

This is a serious matter as it has been generally found that products manufactured by these quarries are substandard and do not meet the requirements of the relevant specifications.

The performance of a pavement is as good as the quality of materials used to construct

Absolutely. A prime example is cement’s role in layer works stabilisation by ameliorating local soils containing undesirable clays. Our purposedesigned product is Roadstab, a specially engineered, composite, high-quality cement that serves as a highly effective stabiliser.

It’s not uncommon to see cement spread by hand ahead of in-situ mechanical stabilisation.

However, a faster alternative is to use our specially designed cement-spreading truck services. Fitted with spreader bars, our drivers are trained to work with site managers to ensure an even application of cement during construction.

We also develop fit-for-purpose cements for structures like bridges. Here, for example, AfriSam High Strength Cement (HSC) has been engineered to render a concrete with a dense matrix, which is desirable in attaining designed service life.

Then for just-in-time delivery, nothing beats high-quality readymix. We have a pump fleet with some of the longest boom reaches in the country, capable of pumping concrete into those hard-to-reach places.

Are there any new road specifications to note?

The COTO draft specification document was issued for implementation in October 2020 and is meant to replace the COLTO document.

Currently, most projects are still utilising COLTO and very few have implemented COTO as

Amit Dawneerangen, GM Sales and Product Technical: AfriSam Construction Materials

22 IMIESA April 2023

ROAD CONSTRUCTION | TECHNOLOGIES, STANDARDS & SPECIFICATIONS

the official specification document. COTO is still receiving commentary from the industry with the aim of updating and revising the various sections.

part of the company’s product development cycle, giving it the scientific and experiential basis to constantly add new innovations to its extensive range of offerings.

How does AfriSam help to lower the carbon footprint?

How exactly does AfriSam measure durability?

We’re the leaders in green cement technology and pride ourselves on providing our customers with products that are environmentally friendly.

One of our flagship brands is the Eco Readymix series, which blends high-performance cement with carbon-neutral mineral components to achieve excellent cementitious properties.

Remarkably, the carbon footprint of this concrete has been reduced by between 46% and 51% compared to typical industry concrete, depending on the compressive strength. The chief reason for this is its lower clinker content, as well as the reduced use of limestone, which is a non-renewable resource.

Within the Eco Readymix range are Starmix, Foundation Mix and Retainer Mix, each developed to meet a particular construction application. Despite their low carbon footprint, their respective performance is far superior to concrete made from pure cements and AfriSam produces ultra-high-performance Eco Readymix concretes with compressive strengths of above 70 MPa.

We are the leaders in durability index testing and have a detailed understanding of how constituent materials and site practices (compaction and curing) impact on the durability and performance of concrete. The AfriSam CPE laboratories are set up to perform the durability index testing and this is available as a service to the construction industry on a commercial basis.

What are some of AfriSam’s key research and development (R&D) projects currently?

By investing in the expertise and systems that sustain quality products, AfriSam is well positioned to conduct and coordinate valuable research into the properties of cements, supplementary cementitious materials, aggregates and concrete. These research projects are initiated and rolled out in collaboration with customers, universities and other bodies.

R&D projects currently underway include a long-term assessment of the effects of highly corrosive environments on concretes made with differing proportions and types of raw materials. Results from these tests feed into dedicated computer software, which allows architects and contractors to specify the appropriate grade of concrete to suit their project’s environmental conditions.

Proactive monitoring, while part of AfriSam’s quality control function, also forms an important

AfriSam operates a readymix pump fleet with some of the longest boom reaches in the country

What type of technical support can clients expect?

AfriSam has a dedicated focus on product quality and an even stronger focus on the correct and optimum use of our products. We believe in knowledge sharing, which includes technical advice and training. Our commitment is to work closely with our clients to help them develop user-specific solutions.

AfriSam offers a range of specialty aggregate for layer works and asphalt designs. This includes aggregates for the base and pavement (G1-G3) as well as sub-base layers (G4-G7)

How can AfriSam help support SMME road contractor development?

AfriSam has been involved for many years in new business development training, providing incubator programmes for people wanting to start small businesses. We also support small contractors through our Technical Department in their use of our products, as well as through our CPE. SMME contractors learn skills such as calculating their bill of quantities and determining the necessary quality of materials they should be using. There are also financial solutions that we offer to smaller businesses to help them deal with their limited liquidity.

In turn, we also expect SMMEs to play their part in terms of this collaboration by bringing their initiative, experience, responsibility and basic expertise to the table. It’s a two-way, evolving partnership.

And in closing?

AfriSam’s technical consultants proactively visit customers on-site to demonstrate the correct use of their product, as well as to identify any cost saving opportunities

projects coming online, together with municipal roads projects.

Alongside major upgrades, there’s also a pressing need for widespread road and bridge maintenance; here, AfriSam’s basket of services are a fit-for-purpose solution.

AfriSam is invested in South Africa and South African construction. Renewed investment in road infrastructure is long overdue; however, we’re starting to see more Sanral

www.afrisam.com

IMIESA April 2023

23

ROADS & BRIDGES

New frontiers in digital engineering

Leveraging the latest advances in digital engineering, SMEC South Africa continues to refine its virtual design capabilities to optimise the construction, maintenance and asset management of transportation routes.

Alastair Currie speaks to Edward Archer, function manager: Roads & Highways, about the key benefits for clients and contractors, citing SMEC’s ongoing work for Trans African Concessions (TRAC) as a prime example.

T

he digital transition from the 2D to the 3D environment, along with the rapid pace of software development, is presenting a whole new range of opportunities for design engineers to add value through the modelling of captured and design data in ways that cannot be replicated by traditional printed drawings,” says Archer.

24 IMIESA April 2023

SMEC’s virtual rendition of the Montrose Interchange on the N4 west of Nelspruit, Mpumalanga. The original provincial road intersection was constructed in the 1970s and required a major upgrade to cope with current traffic volumes. Following a drone survey, SMEC’s design team created a 3D reality mesh using Bentley’s ContextCapture software as a basis for the conceptual design options and further design development

“The speed, accuracy and level of detail are revolutionary, enabling conceptual design development and design updates much more efficiently. Plus, with the use of virtual reality (VR), we can take clients, contractors and stakeholders into the 3D realm and walk, drive or fly them through actual site backdrops, incorporating all interrelated design elements so they can see what works and may not work best in practice.”

Within the transportation space, the bulk of SMEC’s projects are multidisciplinary in nature, encompassing areas that include traffic studies, geometric design, structures, pavements, geotechnical engineering, stormwater, and street lighting.

As Archer points out, prior to digitalisation, coordinating and integrating this volume of multifaceted information was a mammoth task.

Today, however, all of that data is conver ted into a centralised digital model that continues to evolve as each project develops, which has been the case with SMEC’s involvement in various stages of the N4 Maputo Corridor development.

Key sections of this approximately 560 km route – stretching from Pretoria to Maputo – are managed

by TRAC in conjunction with the South African National Roads Agency Limited (Sanral) and its Mozambican counterpart, Administração Nacional de Estradas (ANE).

One of SMEC’s recently completed TRAC projects is an extensive upgrade of an existing N4 two-lane carriageway to an undivided four-lane carriageway (16.4 m sur face width) from east of the Crocodile River bridge (km-distance 0.180) to the Kaalrug/Magnesite mine (D1545) intersection. The length of the road is approximately 15.5 km, with the works completed in Q1 2022.

The detailed design for this project was developed in 2018 and at the time served as one of SMEC’s first major advances in the use of a 3D engineering model to identify all possible conflicts before commencing construction.

Low-impact surveys In the early stages of a project, there is often little time or money to conduct expensive, detailed surveys – especially

ROADS & BRIDGES

when some of the options or concepts might not be implemented. SMEC made many advances in using low-cost survey techniques like unmanned aerial vehicle drone surveys coupled with traditional lidar surveys to produce stunning visuals in record time.

Using a combination of Bentley’s ContextCapture and MicroStation applications, SMEC created reality meshes of several project sites. This was achieved in different ways depending on the source data – in some cases using photogrammetry and in other cases marrying together billions of lidar points used to extract a ground terrain with highresolution aerial imagery to produce a similar result.

SMEC saw the objective of using these digital recreations as the best way to effectively communicate engineering designs in a real-world context.

Digital model SMEC overlays its design model on top of this scalable mesh, bringing in designs from a multitude of CAD applications into a common data environment. This provides rich levels of functionality that include simulation, clash detection, costings, quantities, collaborative design workflow

This 3D reality mesh, created from drone photos alone, was used to diagnose traffic safety issues and communicate concept design options to the client and other stakeholders at a fraction of the cost of a traditional survey

integration across multidisciplinary teams, as well as design review updates.

Starting with the baseline design, and thanks to advances in 3D modelling software, Archer says it is extremely valuable to develop 3D conceptual design models that can be used as a basis for client and community stakeholder discussion during the feasibility phase, and then to interrogate and refine it further during the design development stages to ultimately take the project through to fully digital-driven construction.

A practical example is a future planning study carried out for TRAC at Schoemanskloof, Mpumalanga. Here, the existing road has a speed limitation of 100 km/h due to the challenging terrain and the existing horizontal and vertical curvature of the road. To showcase one option to improve the level of service (LOS), travel time and safety, SMEC submitted a conceptual design overlaid on a scalable mesh design showing a proposed new alignment in an oblique view. TRAC’s engineers were then able to visualise SMEC’s proposal and evaluate the proposed alignment on site.

“There’s no doubt that 3D models convey the message with far more clarity than a conventional cross section or layout drawing – something that clients really appreciate,” Archer explains.

App development

The approved Montrose Interchange design currently under construction.

The interchange occupies the narrow space between the Crocodile and Elands rivers at the start of the old Montrose Pass on the N4

To enhance the digital experience, SMEC has a Management Services Function that develops purpose designed maps and apps for use by its personnel as well as its clients.

“In TRAC’s case, the engineers are using the app to carry out route inspections, future planning scenarios, or to validate design proposals using a tablet to log reports by taking a photo and/or adding a voice or written note.

Since all available terrain information is preloaded, location photos taken are instantly recognised and referenced,” Archer continues.

Traffic studies In terms of its agreement with Sanral

IMIESA April 2023

25

ROADS & BRIDGES and ANE, there are set LOS targets that TRAC must adhere to now and in the future during the concession period, which requires submitting a status report annually. The LOS scale runs from A through F and forms the basis of current operations management and future planning.

An A rating indicates idyllic driving conditions, while an E rating indicates heavy congestion and a situation where road users travel under very poor and frustrating conditions. An F rating, in turn, indicates a complete failure of the facility.

Globally, the Highway Capacity Manual (HCM) issued by America’s Transportation Research Board is one of the benchmarks for measuring traffic flows and calculating LOS. To advance what has traditionally been a manually intensive process of reprocessing HCM calculations for different scenarios, SMEC has created a traffic-centered 560 km digital twin of the entire Maputo Development Corridor as a microsimulation model using the PTV Vissim multimodal traffic flow simulation software. As the term

microscopic implies, this is a highly detailed simulation model.

SMEC has calibrated the model in terms of metrics like driver behaviour, actual travelling speeds measured on the road, and vehicle class performance for every section of the N4 that TRAC is responsible for. This model includes all significant interchanges and intersections on the route. The results of these microsimulations can then be used to advise on infrastructure upgrade requirements to maintain the level of service experienced by road users.

When TRAC submits its LOS report each year, all the latest traffic data recorded at various counting stations, as well as the N4 toll plazas, are analysed and reported on.

Holistic assessment plans and smart designs Another solution developed for the TRAC concession is a holistic assessment plan. “Using our data, we’ve been able to consolidate existing road infrastructure, geometric alignment, heavy vehicle travel speeds and accident statistics over the

past five years and plot them along the route to pinpoint hotspots. We overlay this with the PTV Vissim model analysis to identify where additional lanes and/ or passing lanes are required on specific sections to maximise LOS and improve safety,” Archer continues.

To further refine its delivery models, SMEC is exploring the world of artificial intelligence (AI). “As an AI project experiment, we captured a section of road, with a specific focus on road signs, and ran it through an AI model. Each road sign was automatically georeferenced and positioned in CAD, identified in terms of type and material, dimensioned, and quantified. This exercise definitely shows the potential for AI to process data and use it to promote accuracy and efficiency,” adds Archer.

“Going forward, our objective is to leverage digital technologies to achieve more efficient results and workflows. In this respect, we’ve come a long way in the past five years, constantly shifting the boundaries of virtual design to engineer safer and more effective transportation solutions,” Archer concludes.

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ROADS & BRIDGES

Sanral reports strong project pipeline

N4 SLOW LANE UPGRADE NOW WELL ADVANCED

E

ntrusted with the Pavement Management System for Bakwena Platinum Corridor Concessionaire, JG Afrika is helping to maintain the N1/N4 toll road to the highquality standards specified in the concession contract.

As part of this responsibility, JG Afrika and principal contractor, G4 Civils, are rehabilitating a 20 km section of the slow lane of the N4 between the Kameeldrift and Ga-Rankuwa interchanges.

JG Afrika commenced with the engineering design in 2020 and is now overseeing the construction works, which commenced in January 2022 and are now well advanced for scheduled completion in August 2023.

Construction methodology

T

he South African National Roads Agency SOC Limited (Sanral) awarded 323 tenders to the value of R59 billion in the past financial year. This is a significant increase on the previous period, when tenders worth R22 billion were awarded.

Over and above the tenders awarded by Sanral Head Office and its various regional offices, 12 contracts above R750 million were awarded after the board reviewed the submissions as part of its oversight role.

The total value of these is R28 billion, of which the last four, awarded on 31 March, are split between KwaZulu-Natal and the Eastern Cape.

Supporting SMMEs In line with Sanral’s commitment to economic transformation, at least 30% of the contract value of each tender will be subcontracted to small, medium and micro enterprises (SMMEs). This effectively ensures that close to R18 billion will go to SMMEs located in the various communities in which the projects will be implemented.

Through these awards, the roads agency continues on its positive trajectory to drive economic recovery as part of the broader national effort by government to invest in economic infrastructure. Such significant awards also enable Sanral to squarely respond to the triple challenge of poverty, unemployment and inequality across South Africa through large-scale job creation, skills development and knowledge transfer.

The scope of work entails milling the existing surfacing, base, subbase and a portion of the selected layer. The base and surfacing layers are being milled to a depth of 205 mm and width of 3.7 m, and stockpiled for reuse. In turn, the sub-base and a portion of the selected layer are milled to a depth of 510 mm and width of 3.7 m and sent to a separate stockpile. Roller compactors then compact the remaining selected layer, achieving the required density in five passes.

Hereafter, the milled surfacing and base, as well as 100 mm new G5 material and cement, are placed and stabilised to form a new 300 mm, 3.7 m wide C3 selected layer. A 150 mm bench is then formed on either side of the new base.

After this, a new 150 mm, 4 m wide G1 base consisting of commercially sourced material is placed, and a 150 mm bench formed on either side for the new surfacing, comprising a 60 mm 4.3 m wide continuously graded asphalt layer.

Comments Emma Day, executive associate at JG Afrika: “To mitigate the impact of the construction work on the flow of traffic, rehabilitation, which is being undertaken in sections, needs to be planned very carefully. Unexpected ground conditions, such as areas with underground water, have also been a challenge.”

Breaking down monopolies Furthermore, Sanral states that it remains committed to breaking down monopolies and ensuring meaningful transformation that changes people’s lives for the better. “Our transformation efforts go beyond facilitating access to black-owned businesses. We want them to participate, grow and ultimately prosper,” says Themba Mhambi, board chairperson, Sanral.

To this end, Sanral has embarked on an extensive training and capacity-building campaign, which targets more than 40 000 SMMEs over a three-year period, effectively teaching them to submit compliant, competitive and profitable tenders.

Rehabilitation in progress on a 20 km section of the slow lane of the N4 between the Kameeldrift and Ga-Rankuwa interchanges

IMIESA April 2023

27

ROADS & BRIDGES

The Society for Asphalt Technology (SAT) has bounced back strongly from the pandemicinduced isolation with new leadership, fresh ideas and a revived passion for networking.

W

e have learned a lot about adapting to change in the past few years and this will ser ve us well as we plan for the future,” says John Onraet, operations manager, SAT. “We are aware, more than ever, of our responsibility as members of SAT to suppor t sustainability and growth in our industr y through uncer tain times.”

In the past few months, SAT has seen the inauguration of a new president, Krishna Naidoo (Sanral), and election of its new vice-president, Joanne Muller (AECI Much Asphalt). Imraan Amien

DOING MORE FOR OUR ASPHALT INDUSTRY (PHB/Ensync Engineers) remains the only standing regional chair following his acceptance of re-election in the Southern Region. The Central Region – representing Gauteng, the nor thern provinces, and neighbouring countries – has welcomed Tafadzwa Mafuma (AECI Much Asphalt) to the helm. Lee McNeil (Ten Civils) is the new chair of the Eastern Region, and Nik Berning (Liesen Bitumen) leads the Eastern Cape Region.

Events Herman Marais

John Onraet, operations manager, SAT

28 IMIESA April 2023

his tenure, along with a continuous drive to rethink SAT’s priorities. This foresight has created a platform from which to launch various initiatives now being planned and actioned.

Krishna Naidoo and Joanne Muller are leading the drive to add more value for current and prospective SAT members, with significant focus on leveraging their collective exper tise and experience.

Herman Marais, the fifth president of SAT, has ser ved the society in several capacities for many years, culminating in five years as president.

The incoming president, Krishna Naidoo, has paid tribute to Marais for building a solid foundation for SAT through “excellent ser vice, suppor t, leadership, guidance and inspiration”.

Marais has been praised for his consistency, his culture of always showing up, and his diligent and levelheaded steering of the ship. However, he was not afraid of change and played a major role in the success of the first two SATBinderrr conferences amid the pandemic. He also led a complete rebranding of SAT during

SAT has a busy diar y planned for 2023. The Central and Eastern regions have already co-hosted a successful joint hybrid event around the basic principles of raw materials.

In-person workshops were hosted in Gauteng and Durban, with online presence countr ywide.

An event seeking solutions to challenges in the industr y in collaboration with the international asphalt sector (including sub-Saharan Africa, France, Germany and Australia) has also drawn strong interest.

Regional and national events planned for the rest of 2023 include workshops on critical issues, site visits, shor t single-topic educational events, and networking sessions.

ROADS & BRIDGES

The hybrid model, tested at the 2022 SATBinderrr conference, is proving successful and inclusive.

SAT is also pleased to be playing a leading role in the CAPSA 23 conference planned for October with several members on the organising committee and expected to present papers.

Upskilling presenters A review of SATBinderrr 2022 has resulted in some exciting new developments that will elevate future events. These include the acquisition of professional audio equipment to improve the overall experience for attendees across all SAT events, as well as access to a well-priced course to assist SAT members with presentation skills.

“We are excited about the new level of professionalism we hope to achieve through both of these developments,” says Onraet. “The presentation skills

course will also add ongoing value for members in their jobs outside of SAT and we hope to attract funding from employers to assist this initiative.”

SAT is also engaging more closely with international asphalt associations in the interests of sharing best practice and collaborating globally on industr y issues. This ‘International Series’ of industr y events is planned as an ongoing focus area for SAT.

Student membership Young, talented professionals are needed in the industr y and SAT is focusing on attracting student members to help instill an interest in asphalt among young people entering technical careers. “We have several leading exper ts and academics on our national and regional committees who are assisting us in our campaign to get more student members on board,” says Onraet. He points out that access to many of the industr y’s

CREATE A LIFETIME BOND WITH MAPEI

leading professionals and the large, growing body of published work through SAT is extremely valuable for student members.

Innovative ways to fund the annual fees for students are currently being discussed. “We know students are illequipped to pay the fees, so we need to assist them until they are employed.”

A new SAT-hosted competition for pavement/asphalt-related undergraduate projects countr ywide will be launched this year to improve awareness of SAT among undergraduates and promote involvement in the industr y at graduate level.

A little fur ther down the road but equally exciting is the development of a dedicated SAT app.

“We can’t reveal much about this yet,” says Onraet. “But it is just one par t of our drive to stay relevant, to ensure our sustainability, and to add more value.”

ROADS & BRIDGES

Customer appreciation day

for asphalt clients

Overview of the control cabin

Customers touring the Eerste Rivier plant

L-R: Renaldo Goodwin, branch manager: Contermanskloof, AECI Much Asphalt; Candice Josias, regional sales manager, AECI Much Asphalt; Mampho Sotshongaye, managing director of Golden Rewards 1981; Thembi Mbusi of Golden Rewards 1981; and Randall Koopman of ROK Civils

L-R: Francois van der Spuy, project manager at AECI Much Asphalt, along with Frans de Jongh and Frik de Jongh of Jumbo Tar

Deon Pretorius of Estrada Construction (left), and Noloyiso Mafenuka, sales manager: Western Cape, AECI SprayPave

30 IMIESA April 2023

ROADS & BRIDGES

Hilton Duplessis (left), production supervisor: Eerste Rivier, AECI Much Asphalt; and Renaldo Goodwin, branch manager: Contermanskloof, AECI Much Asphalt

L-R: Candice Josias, regional sales manager, AECI Much Asphalt; Nicky Gerste of NDG Construction, winner of 10 tonnes of pavement mix in the raffle draw; and Bruce Anstis, branch manager: Eerste Rivier, AECI Much Asphalt

L-R: Reginald Ferreira, weighbridge supervisor: Eerste Rivier, AECI Much Asphalt; Delicia Lackay and Germaine Koopman of Four Stones Civils; as well as Rumarques Brown, production manager: Western Cape, AECI SprayPave

D

uring March 2023, AECI Much Asphalt hosted 31 customers at the Eerste Rivier plant and Central Laboratory in Cape Town to celebrate long-term relationships and catch up with old and new friends.

“The event not only enabled us to reconnect with clients in person, but also to showcase our plant, products and laboratory capabilities,” says Brendon Masters, regional manager, AECI Much Asphalt.

Several new managers have been appointed recently in the Western Cape. These include Masters, who has worked for AECI Much Asphalt for almost 30 years and moved from Contermanskloof as branch manager to Eerste Rivier as regional manager in 2022.

Other new managers include Renaldo Goodwin, branch manager: Contermanskloof; Bruce Anstis, branch manager: Eerste Rivier; Candice Josias, regional sales manager: Western Cape; and Angel Nomatiti, branch manager: George.

The George plant falls under the Western Cape region.

Masters adds: “The idea of the event was to introduce the team and show our appreciation to all our customers, no matter how big or small, for their support. We place great value in meeting face to face and will continue these events in future.”

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METRO FOCUS: NELSON MANDELA BAY

South Africa’s largest

BIOFILTRATION PLANT NOW OPERATIONAL

The Coegakop WTW is possibly the most ambitious biological manganese removal plant in the world

Par t of the Coegakop Wellfield Project, the Coegakop Water Treatment Works (WTW) is designed to treat groundwater to potable standards for drought-stricken Nelson Mandela Bay Municipality (NMBM).

N

ot only the largest biofiltration plant of its kind in South Africa, the Coegakop WTW is possibly the most ambitious biological manganese removal plant in the world (treating high concentrations up to 2 500 mg/ℓ).

Preekstoel Plant in Hermanus is the only other biofiltration plant of this kind in the countr y, but it can only treat 10 Mℓ/day, as opposed to the 20 Mℓ/day treatment capacity of the Coegekop WTW

What is biofiltration and why use it?

Biofiltration is a biological method of treating water whereby a specific culture of autotrophic bacteria is allowed to grow on a filter media to aid in the removal of dissolved minerals. These bacteria are chemosynthetic, utilising chemical energy released when they use oxygen to oxidise the metals. They are of the same type of bacteria as those found in wastewater treatment works to convert ammonia to nitrate and are harmless to humans.

“The Coegakop WTW uses biofiltration technology because it is an affordable, efficient, sustainable and reliable treatment solution with low maintenance costs. The normal filtration process requires the use of more chemicals, so Matthew Hills, civil engineer, NMBM

32 IMIESA April 2023

this approach reduces our operational cost and is also better for the environment,” explains Matthew Hills, civil engineer: Water & Sanitation Subdirectorate, NMBM. Hills adds that the cost per kilolitre of water is less than alternative water sources for NMBM. “NMBM is confident that Coegakop will supply the lowest cost per kilolitre of water within the NMBM water supply system. Aside from the iron and manganese elements, the water is pristine and characterised by low levels of salinity.”

Besides the water purification, there are negligible bulk water transfer costs, since the treated water goes straight to the existing Coegakop reser voir approximately 650 m away. From there, distribution pipelines supply areas of Mother well, Colchester and the Coega SEZ. “Having a second source of water supplying the Coega SEZ is essential for

METRO FOCUS: NELSON MANDELA BAY

investor confidence and will unlock the potential for further development and job creation,” says Hills.

The treatment process primarily involves biological oxidation and filtration of iron and manganese, as well as the stabilisation and disinfection of groundwater from the Coegakop Wellfield.

The project Groundwater initially enters the works showcases NMBM’s The boreholes at Coegakop at the raw water inlet chamber where pH recover y ponds where the ability to deliver highare equipped with level and and oxygen levels are adjusted before solid residue settles, quality, innovative flow sensors linked to the the water is distributed to the sand and the supernatant infrastructure to the community Scada system. Overall, this filters. Interesting, the water temperature is pumped back to the determines how abstraction rates is around 27°C due to the depth of head of the works. Settled affect the overall aquifer. Effects of the aquifer. solids are allowed to dr y over abstraction are monitored on boreholes There is a two-stage biofiltration time and are periodically removed for further upstream of the Coegakop treatment process removing iron and then disposal off-site.

Wellfield near Kariega. This information manganese. The iron and manganese This treatment process relies on is transferred to the Coegakop WTW in the groundwater are initially in a interstage filter feed pumps, backwash and shown on the plant Scada. This will dissolved state and cannot be removed pumps, backwash blowers and treated ensure that timely inter ventions can be by conventional filtration alone. Inside the water high-lift pumps. made to the abstraction rates to prevent filters are dedicated strains of bacteria that Sophisticated monitoring any detrimental groundwater draw-down are cultivated to facilitate the oxidation and control effects and negative impacts to existing of iron and manganese. Solid precipitate Automated control and instrumentation aquifer users. particles are formed and then filtered out. systems will ensure that the treatment The data will also prove invaluable for The filtrate then flows by gravity through process operates effectively and that the Department of Water and Sanitation in a packed limestone bed, stabilising the the process controllers can monitor all monitoring aquifer health and water use in pH levels. From there, it moves into a activities centrally. Automated reporting will terms of the licensed aquifer abstraction. treated water storage tank. A residual be generated, assisting with compliance dose of chlorine (as calcium hypochlorite) In conclusion reporting. This is primarily done through a is added into the treated water storage The project involved rigorous and highly Scada system. tank, controlled by a chip-feeder dosing collaborative interaction between the client, “NMBM is refining its ability to operate system. This is done to protect water engineers, architects, hydrogeologists, plants remotely, as well as record, view against downstream contamination. The environmental practitioners, 3D software and manage data. With the drought, the treated water is then pumped to the modellers and virtual reality programmers. balance between water demand versus Coegakop reser voir for distribution to “The Coegakop WTW is an incredible available supply is precarious and we NMBM communities. achievement. It showcases NMBM’s need to react rapidly to any changes within The filters are backwashed with a ability to deliver high-quality, innovative this system. Adopting a modern Scada combined water/air-scour system, infrastructure to the community, and it system is a huge step in the right drawing water from the manganese is a strong reminder that we as South direction towards achieving filtrate tank, and supplying air The water Africans can and should take a leading an optimised, efficient and from dedicated backwash temperature is around 27°C due role in solving our own water challenges,” reliable water supply system,” blowers. The spent backwash to the depth of the Hills concludes. explains Hills. water is fed to backwash water aquifer.

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TRENCHLESS TECHNOLOGIES

Trenchless techniques

HAVE PROVEN ADVANTAGES THAT NEED EXPLORING In recent years, there have been widespread media repor ts concerning the water problem facing South Africa and the amount of drinking water being lost before reaching the public. Possibly up to 40% of the extracted water is lost due to leaking supply pipelines. By Alaster Goyns, Pr Eng*

W

ith wastewater, there is a similar situation, where sewers are leaking and polluting the natural water courses. During wet periods, these sewers are surcharged with groundwater flowing into them through the leaks and causing the overloading of wastewater

A seriously corroded cast iron pipeline

treatment facilities. Urgent remediation interventions are therefore required.

One option is to replace the pipes; however, another far more beneficial approach is to rehabilitate them using trenchless technology (TT) – a technique that has proven beneficial worldwide, but with less prominence to date in South Africa.

For towns and cities, one of the key construction challenges in replacing pipelines is urban densification. This is where trenchless interventions excel, being generally more cost-effective and far less socially and environmentally disruptive.

There are a broad range of TT solutions to choose from, depending on the degree of degradation in scenarios where pipelines are partially or fully deteriorated and close to collapsing. Here, TT pipelining applications are highly efficient. They entail the insertion of tightfitting smooth liners within existing pipelines, often resulting in a slight improvement in the capacity of the buried conduits.

These linings are continuous from manhole to manhole. Additionally, they are made from materials that are strong and impermeable, thereby eliminating problems with leaking joints.

For new infrastructure, or where existing pipes need to be replaced or upgraded in terms of capacity, common TT applications – each one being project-specific – include pipe bursting, horizontal directional drilling, pipejacking and microtunnelling. In most cases, these systems can be installed with minimum need for excavation, making them ideal for situations where services need to be installed under road and rail networks, as well as residential and commercial developments.

Geotechnical investigations

A relined pipeline negotiating a curve

34 IMIESA April 2023

In dealing with buried conduits, whether they will be placed in open trenches or using TT techniques, it is essential to understand what the site conditions are before any design or construction takes place. Surface inspections do not provide information about what is underground and what buried problems there may be. So, an essential activity before any trenched or trenchless construction is commenced is to do an investigation of the conditions beneath the surface to a level below where the construction is to take place.

TRENCHLESS TECHNOLOGIES

SASTT WEBINAR SERIES 2023 Programme and Dates • General introduction to TT activities: 6 June 2023 • Performance and condition assessment of existing pipelines: 11 July 2023 • Pipe lining techniques, such as slip lining, cured-in-place-pipe and others: 12 September 2023 • On-line replacement techniques such as pipe bursting: 14 November 2023 2024 Programme • New installations – short crossings such as moling, ramming and pipejacking • New installations – long crossings such as directional drilling and microtunnelling • Supporting services such as pipe cleaning and over-pumping • International developments www.sastt.org.za

Performance and condition assessment When it comes to the rehabilitation or upsizing of installed conduits, it is essential that their performance as well as their condition be assessed. By combining this with the site investigations, problems can be identified and their underlying causes usually determined.

Doing this means most of the problems that could arise during construction are identified and the necessary measures to avoid them can be taken. While this may be seen as incurring added cost at the beginning of a project, in the long run, it saves time, money and minimises claims due to unforeseen conditions.

Showcasing the benefits: the SASTT webinar series Locally, TT practitioners – comprising consulting engineers, contractors, and OEMs – are represented as a body by the Southern African Society of Trenchless Technology (SASTT). The latter is recognised as a registered Voluntary Association by the Engineering Council of South Africa.

As part of its engagement, SASTT regularly runs industry events and workshops, which will now be expanded to include the phased introduction of a series of eight short webinars over the next two years. These webinars will cover the various techniques available for the installation, rehabilitation, repair, and replacement of buried conduits with minimal excavation.

The purpose of these events is to inform all role players involved in the planning, design,

construction, operations and maintenance of buried pipelines about the role of TT in preserving and enhancing South Africa’s water and wastewater infrastructure. Local experience is benchmarked against global best practice via SASTT’s affiliate membership of the International Society of Trenchless Technology (ISTT).

SASTT’s webinar series will cover the full spectrum of trenchless techniques locally available. (See the SASTT Webinar Series box on the left for the 2023/24 programme.) As well as providing an overview of the topics, each webinar will cover the hydraulic, structural, watertightness and durability requirements for specific TT techniques, with reference to realworld case studies.

The webinars, which will be hosted via 3S Media’s webinar platform, earn Continuing Professional Development (CPD) points and will serve as invaluable building blocks towards a far greater appreciation of the proven value of TT to maximise asset management utilisation and sustain socio-economic development. *Individual member of the Southern African Society for Trenchless Technology (SASTT) and owner of PIPES cc

TRENCHLESS TECHNOLOGIES

Design considerations for new pipelines and rehabilitating pipelines with linings Irrespective of whether a pipeline is a gravity or a pressure system – and whether it is new or one due to be rehabilitated – there are four basic requirements that must be met, namely hydraulic per formance, strength, water-tightness and durability. By Alaster Goyns, Pr Eng*

T

he primary function is hydraulic capacity and performance. This is determined for anticipated future demand within 20 or 30 years. Other requirements ensure that the primary one is met and can continue to do so even after the capacity demand has been reached, making an additional pipeline necessary to meet the required future capacity.

36 IMIESA April 2023

Pipeline failure can be either functional, when it is unable to meet the demand, or more serious when one of the other requirements is not met. Functional failure occurs when the demand is greater than the capacity and is generally a temporar y condition that occurs with increasing frequency as a pipeline ages. A nonfunctional failure is not temporar y and results in deteriorating pipeline condition

and eventual structural failure if no remedial measures are taken.

When considering how to cope with the failure of a pipeline, a clear distinction must be drawn between a functional failure due to the inability to meet its required hydraulic per formance, and failure to meet one of the secondar y requirements when its deteriorating condition will eventually lead to a structural collapse and an inability to per form at all. With a functional failure, the pipeline can be upsized or an additional pipeline installed.

When one or more of the secondar y requirements deteriorate, the primar y requirement may still be met for some time, but a structural collapse will occur eventually due to a combination of these factors. Hence it is essential to assess the per formance and condition of pipelines to identify any problems, determine the underlying causes, and take the necessar y

TRENCHLESS TECHNOLOGIES

remedial action to ensure that they can continue per forming satisfactorily.

Pipe subject to internal pressure expands around whole circumference

Pipe subject to external load is squashed vertically and expands horizontally

Gravity versus pressure systems Trenchless techniques for the rehabilitation of pipelines using linings to reinstate their structural, watertightness and durability requirements are similar, whether gravity or pressure systems. However, differences need to be considered when doing the structural design of the lining to be used.

The major difference is due to the loading cases to be considered. With gravity systems, the lining needs to be designed for the groundwater pressure that develops between the liner and host pipeline due to leaks into the system. It needs to be designed so that it does not buckle under the maximum value of this pressure when the pipeline is empty. For pressure systems, the liner must be designed for the maximum internal pressure, as well as for external pressure that may occur when the pipeline is empty.

With gravity and pressure systems, the pressure between the host pipe and the lining differs. For the gravity system, this pressure will depend upon the maximum water level above the pipeline invert, which may be at the groundwater level or, under certain circumstances, at the level of flood waters above ground level. For the pressure system, there may be a leak in the pipeline at a high point. When a lining is placed, this water can then flow down to a low point and result in significant pressure between the host pipe and the lining. Under these circumstances, it may be necessar y to take additional measures to reduce the magnitude of this pressure.

Installation of a cured-in-place liner for a sewer line rehabilitation project

Preventing buckling or bursting There is a significant difference in the structural requirements for a pipeline or a lining to handle external forces to prevent buckling and those required to handle internal pressures to prevent bursting. The buckling resistance is dependent upon the wall thickness to the power of 3, whereas the internal pressure is directly related to the wall thickness. This is shown in the formulae to be used for the two different loading cases.

For external loading, it is the pipe ring stiffness (PRS) that resists the buckling and this is calculated from:

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TRENCHLESS TECHNOLOGIES

PRS = EI/D3 = (E/12) x (t/D)3 where PRS is pipe ring stiffness E is Young’s modulus of pipe material I is moment of inertia of pipe wall = t3 /12 t is pipe wall thickness D is mean pipe diameter For internal pressure, it is the direct tensile stress, called the hoop stress, that resists the internal pressure and this is calculated from: σ = (pD)/(2t) where σ is circumferential hoop stress in pipe wall p is internal pressure in pipe D is the mean pipe diameter t is pipe wall thickness To determine the structural requirements of a pipeline to handle internal pressure, the same approach will be taken irrespective of the pipe material being used; however, when determining these requirements to handle the external loads, there is a clear distinction between the approach taken depending on whether the pipes are rigid or flexible. Differences in the per formance of the pipes, or linings when subject to Spirally wound pipe lining technology employed during the rehabilitation of a section of the Cape Flats 1 sewer line in Cape Town

internal pressures and external loads, will depend upon the pipe, and lining material properties.

Installation and founding conditions With a new pipeline, its external load carr ying capacity depends upon the installation and founding conditions, as well as the relationship between the pipe stiffness and soil stiffness. With rigid pipe materials, such as vitrified clay, concrete or fibre cement, the load will be sensitive to the actual installation that could be in a trench, under an embankment, or in a tunnel, and the founding conditions, which could var y from yielding to unyielding.

The bedding support will enable the installed pipe to carr y up to 2.5 times the load that it could carr y in a factor y test.

The combination of these factors can make a significant difference to the strength of pipe required for a given situation.

With flexible pipe materials such as polypropylene (HDPE), polyvinyl chloride (PVC), glass-reinforced plastic (GRP) or steel, the support from the embedment around the pipe enables it to carry as much as 12 times the load that it could carry in a factory test. In addition, a pipe made from a flexible material will deform under load and shed the load onto the columns of earth on either side of it.

The combination of these factors means that the rigid pipe will carry between 40% and 90% of the external load imposed on it and the bedding will carry between 10% and 60% of this load. This combination of factors will result in the flexible pipe carrying only between 5% and 20% of the external load imposed on it, while the embedment will carry between 80% and 95% of this load.

This explains why the load carrying capacity of rigid pipes is dependent mainly upon their installation and founding conditions, whereas the load carrying capacity of flexible pipes is dependent mainly upon the strength and support provided by the surrounding embedment material.

Rigid or flexible With the structural design of a new pipeline to carry external loads, the procedure depends upon whether the pipe is rigid or flexible.

In both cases, the load carrying capacity depends upon the pipe/soil interaction but, in the case of the rigid pipe, the pipe strength

38 IMIESA April 2023

is the critical factor. With flexible pipe, the pipe deflection is critical. In simple terms, this can be expressed for the rigid pipe as: Pipe strength = Load on pipe/Soil

strength For a flexible pipe this can be expressed as: Pipe deflection = Load on pipe/(Pipe

stiffness + Soil stiffness) There are differences and similarities in the way that pipes, and linings within pipes, handle these loads and pressures.

When comparing a new pipeline being installed versus one being relined, the interaction between the pipe and the soil is critical with a new pipeline; with a relined pipeline, it is the interaction between the host pipe and the lining. When an existing pipeline is being rehabilitated with a lining, the external loading on the lining will depend upon the deterioration of the host pipe. If the host pipe is still structurally sound, but is leaking or starting to show signs of durability problems, cleaning and lining the pipeline will rectify these problems, but there will be an accumulation of water pressure between the host pipe and the liner. The pipeline would also be classified as partially deteriorated.

Under these conditions, the liner will just be designed to handle the water pressure between it and the host pipe. However, if the host pipe is structurally unsound and could be expected to collapse in the near future, it is then classified as fully deteriorated. Under these conditions, the liner is designed to handle both the external water pressure, plus the earth and traffic loading being carried by the host pipe.

In both cases, the lining may receive some radial support against buckling due to water pressure between the host pipe and the liner. The liner in a partially deteriorated host pipe will fit tightly within the host pipe and this will enhancement its ability to resist the groundwater pressure. However, with a fully deteriorated host pipe, the liner is designed to take the full external load, consisting of water pressure, earth loads and traffic loads, with no assistance from the host pipe. Over time, the loading on pipelines may change from those when they were first installed depending upon surrounding soil conditions.

This should be checked when evaluating the condition of a pipeline to be rehabilitated. *Individual member of the Southern African Society for Trenchless Technology (SASTT) and owner of PIPES cc

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TRENCHLESS TECHNOLOGIES

Novel culvert jacking project showcases creative thinking With more than 200 projects completed to date, BLOC Contractors continues to refine its specialist skills in the geotechnical engineering and trenchless technology fields. As company director Byron Field explains, no two jobs are alike, so innovation is key to per fecting the right methodology.

O

ne of BLOC’s recent milestone projects serves as a prime example of the expertise and precision required to install new subterranean services under live railway conditions.

Situated in Inyoni, KwaZulu-Natal, the project scope entailed the establishment of two pedestrian culvert underpasses beneath sections of Transnet lines to enable access to new RDP houses implemented by the KwaZuluNatal Department of Human Settlements. The culverts also needed to be wide enough to accommodate the movement of cattle owned by small-scale farmers in the area.

In conjunction with BVi Consulting Engineers, BLOC devised a design and construct culvert jacking solution to install the two 3.5 m wide by 2.5 m high culverts, one measuring 26 m and the other 28 m in length.

“Conventionally, a common methodology in congested urban settings is to advance the

installation incrementally with precast culvert sections to complete the structure. However, since we had lots of space to work with in this rural setting, we opted to install each culvert as a preconstructed unit,” says Field.

“That required a lot of room for out-of-the-box thinking to perfect this trenchless approach, considering that each culvert weighs around 500 tonnes. But the weight was not the main challenge. The primary one was to manage the drag,” Field continues.

concrete strength had been attained, the jacking programme commenced in conjunction with progressive tunnelling operations through the railway embankments at a steady advance rate.

“We generally tunnelled for 0.5 m, and then jacked the culvert element forward in a constant cycle until we came out the other side,” Field explains, adding that it took around two and a half months to push the culverts through their respective sections.

Preparing to launch In preparation for the launch, a casting floor was constructed for each of the two culvert sites, incorporating an anchored thrust block purpose-designed by BLOC. To firmly secure the thrust block in position, anchor cables were installed by drilling down some 18 m to reach bedrock.

Then, once BLOC had completed the construction of the culverts and the required

INYONI PEDESTRIAN CULVERT UNDERPASS JACKING PROJECT

Anchor cables were installed by drilling down some 18 m to reach bedrock The anchored thrust block purpose-designed

by BLOC Contractors for the project

One of two completed culverts constructed

40 IMIESA April 2023

Preparation of ground anchors for the thrust block

TRENCHLESS TECHNOLOGIES

smooth. This ensures that the sheet remains static, while the culvert slides smoothly forward.

The system worked perfectly,” Field expands.

Hydraulic cylinders employed to push the culvert forward

Current work nationally

Reducing the drag coefficient One of the key concerns during the design stage was the limited overhead cover above the culverts, comprising engineered fill varying in depth from 1.5 m to 2 m. Since engineered fill is not as stable as in-situ natural ground, this had to be factored in due to the high drag loads generated during the jacking programme.

In principle, the risk existed that the railway lines could be pulled sideways during the underground thrusting process.

To ensure that didn’t happen, a specialist HDPE liner sheet technology was employed. Fed from the front and over the top of the culvert during the tunnel advance, the continuous sheet acted as a membrane barrier between the culvert and the overhead fill, greatly reducing the degree of friction.

“The top side of the sheet incorporates anchor knobs that embed into the overhead ground, while the underside of the sheet is completely

Alongside its pipe- and culvert-jacking contracts, BLOC has been working extensively on lateral support projects focused on reinstating structures and embankments damaged by the widespread flooding that occurred in eThekwini and beyond during 2022.

In parallel are a series of national infrastructure projects that support the installation of water and sanitation pipeline services. Examples include a project in Fleurhof, Gauteng, where BLOC has installed the underground services for a private residential development in conjunction with municipal entity Johannesburg Water. The scope entailed six pipejacking phases over a five-month period.

Back in KwaZulu-Natal, BLOC recently mobilised on-site to complete a four-phase pipejacking project for a sewer outfall within Harry Gwala District Municipality.

Further afield in Mpumalanga, there are also a series of new projects underway. Current work includes a project with four pipejacked crossings within Gert Sibanda District Municipality, entailing the installation of bulk water pipeline services in Balfour.

BLOC also recently completed a stormwater upgrade project in eMalahleni Local Municipality in conjunction with toll road concessionaire TRAC N4.

Setting the scene, an existing 30 m long Armco stormwater pipe travelling under the N4 had been scavenged over time for scrap

metal, potentially threatening the integrity of the road by creating an unsupported void. To remediate the situation, BLOC jacked through a precast concrete pipe. The existing voids were in turn filled with grouting as part of the stabilisation works.

“From a time and cost perspective, trenchless techniques are ideal for the installation of below-ground services because they greatly reduce the need for open trench excavation, especially beneficial in dense urban areas.

However, in the case of projects like Inyoni and the N4, it’s also the only viable approach to ensure that existing infrastructure remains intact,” Field concludes.

Each of the two culverts is 3.5 m wide by 2.5 m high

Limited ground cover of between 1.5 m and 2 m required an innovative solution to enable a safe jacking methodology

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TRENCHLESS TECHNOLOGIES

Slurry microtunnelling solutions for SA hard rock conditions Global population growth and increasing urbanisation are forcing cities to develop sustainable infrastructure for traffic, utility service supply and disposal networks.

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esides the drinking water supply, wastewater handling plays a fundamental role in urban development schemes. Thus, the large-scale provision of an efficient sewerage system is a major challenge in the steadily growing cities of South Africa. Existing networks have to be expanded and new high-capacity schemes built to meet future requirements in increasing sewage volume and growing challenges in flood protection.

The role of mechanised tunnelling For South Africa’s upcoming water and sewage disposal projects, mechanised tunnelling and microtunnelling are indispensable to install the required

infrastructure underground, with minimum impact on the sur face.

Besides segment lining, which is mostly used to build main collector tunnels (ID ≥ 3 000 mm), microtunnelling with slurr y pipejacking equipment has a long tradition in trenchless construction of sewer networks and link sewers. On an international scale, technological advancements and valuable experience gained by the contractors have pushed the boundaries in microtunnelling in terms of achievable drive length, tunnel diameter and ground conditions.

In the planning stage of tunnelling projects, clients and planners need a broad knowledge about the available technologies and the feasibility limits to

go for in choosing the best suited and most efficient method. Subsequently, the close cooperation of technology supplier and contractors to design the tunnelling equipment will ensure a safe and reliable project execution.

Slurry microtunnelling in South Africa With a rising number of projects executed with slurr y microtunnelling in South Africa, clients and consultants are becoming more and more aware of the possibilities this technology offers. In addition, safety aspects are becoming more important in the construction industr y. Remotely controlled microtunnelling is therefore an alternative to conventional methods, especially in the non-accessible diameter range (ID < 1 200 mm).

More than 10 years ago, the first Herrenknecht slurr y microtunnelling had been used for utility projects in Durban.

Later on, several AVN machines (ID 800/ 1 200 mm) successfully completed sewer projects in Cape Town, such as the Cape Flats 3 Bulk Sewer Phase 2 and Southern Corridor Farm 694 Bulk Sewer, for example.

Other potential projects are being planned such as Philippi Sewer and Montague Drive Bulk Sewer in Cape Town, uMKhomazi Bulk Water Supply and the proposed tunnel in Buffalo City (East London).

Hard rock conditions The challenging ground conditions in South Africa, mainly consisting of hard rock,

A Herrenknecht AVN 1000 being lowered into the launch shaft on the Cape Flats – Khayelitsha Main Water Supply Pipeline Project in 2021

42 IMIESA April 2023

TRENCHLESS TECHNOLOGIES

AVN 800 HR for hard rock with compact jacking station prepared for drive in test mine

• compact jacking frame to achieve a small launch shaft of Ø 3.2 m • operation by standard control container C20 possible • flushing ring: fine rock particles to be kept away from annulus • extension kit OD 1 295 mm with rock cutting wheel, up to 80 MPa possible.

Cutting wheel design and tooling

require special solutions for tunnelling equipment in order to make projects economically and technically feasible.

The continuous further development of slurr y microtunnelling is important to cope with the var ying geological conditions, including weathered rock, rock-soil transitions, as well as fractured and intact hard rock with high strength and abrasivity.

In the past, in hard rock conditions, the applicability of slurr y microtunnelling has been especially limited in the nonaccessible diameter range.

Nowadays, the ever-growing number of microtunnelling projects in hard rock conditions is mainly driven by recent technological developments to overcome the limitations in drive length and to improve per formance.

AVN 800 for hard rock With the recent development of the power ful AVN 800 HR (OD 975 mm) for hard rock, Herrenknecht has developed a new machine type, which per fectly fits the

South African standard pipe diameter for sewerage projects. This microtunnelling TBM (MTBM) is equipped with a stronger main bearing and an adapted cutting wheel design.

The machine excavates the rock with a jacking force that is three times higher on the cutting wheel in comparison to the traditional AVN of the same size. A flushing ring at the bottom of the machine with remote-controlled ball valve prevents fine particles in the annulus, thus reducing jacking forces.

Technical improvements: • for rock with high uniaxial compressive strength (UCS): up to 200 MPa • extended drive length: up to 200 m • high wear-resistance of TCI cutter discs • increased rotation speed of cutting head: up to 26 rpm @ 260 ℓ/min • stronger main bearing: 89 t

The cutting wheel’s tooling composition is the most critical part in rock applications.

Tool size and arrangement are determined based on the rock properties in order to obtain reasonable rock chip sizes that can be handled by the discharge system. Three main cutting tool types can be considered for MTBMs: disc cutters, TCI cutters or milled tooth cutters.

The most common cutting tool remains the disc cutter, which is well known from large-diameter hard rock TBMs. However, due to space constraints, the disc cutter is normally modified into a double or triple disc cutter, which decreases the spacing and therefore leads to faster chipping of the rock.

On the other side, the larger number of rings on cutters decreases the available thrust force per ring and therefore decreases the probability of creating tensile cracks that lead to chipping. This makes it important that

Hard rock cutting wheel design and TCI cutter

With the recent development of the powerful AVN 800 HR (OD 975 mm) for hard rock, Herrenknecht has developed a new machine type, which perfectly fits the South African standard pipe diameter for sewage projects

IMIESA April 2023

43

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TRENCHLESS TECHNOLOGIES

small-diameter hard rock AVN machines have a capability of high jacking forces and both a strong main bearing and cutter bearing.

If this problem cannot be solved with a technical solution, or if a high requirement on the lifetime of the cutters exists, TCI or button cutters are recommended. This cutter type has also been chosen for the AVN 800 HR. TCI cutters exert a point load force on the rock, resulting in numerous small chips.

Due to the tungsten carbide insert, the TCI cutter is considered especially wearresistant, which is beneficial for long drives in small diameters, where cutterhead inter ventions are not possible.

AVN 800 HR in operation The first tests of the AVN 800 HR equipment took place in early 2017 in Germany. In the meanwhile, several AVN 800 HR MTBMs are or have been in operation worldwide – e.g. in Australia, Brazil and Scandinavia.

One example of a successful reference project is the Water Main Improvement Project in Hong Kong in 2020. Slurr y microtunnelling was selected as the preferred method to install the 107 m long section, with a constant radius of 153 m on a sewerage project, owned by the Water Supplies Department.

The complete tunnel alignment led through granitic rock with a maximum UCS of up to 200 MPa. Due to these hard rock conditions and the small diameter of only 960 mm (OD), an AVN 800 HR for

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hard rock was selected. As cutting tools, conical 317 mm cutters with TCI inserts were selected.

The AVN 800 HR has an installed power of 90 kW, enabling a maximum cutting wheel rotation speed of 26 rpm and a maximum torque of 55 kNm. Thanks to the innovative cutting tool choice, it took only 60 days to complete the drive, including several idle days.

Impact for the trenchless industry This AVN 800 for hard rock will push the boundaries of what is possible in smalldiameter microtunnelling in terms of feasible drive length in hard rock conditions.

Longer drives make microtunnelling a more economic and environmentally friendly construction method. The number of shafts can be reduced, impact on the surface can be minimised, and the construction of larger tunnels only for access reasons can be avoided in certain projects.

Furthermore, new opportunities for clients and consultants in the planning of tunnel routes for different infrastructure installations can be considered, making trenchless technologies even more competitive and cost-effective, while improving public acceptance at the same time.

Conclusion Thanks to major technical developments such as innovations in machine per formance, cutting tool design, peripheral equipment and digital

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ABOUT HERRENKNECHT AG Herrenknecht looks back on 45 years of experience in mechanised tunnelling. As the world´s leading manufacturer of tunnelling equipment, Herrenknecht maintains a close partnership with its customers, who have successfully completed countless tunnelling projects worldwide.

Based on an international service network and reliable technology not only for tunnelling, but also for pipeline, mining and shaft sinking applications, Herrenknecht provides mechanised solutions for ambitious upcoming projects and their successful completion.

solutions, the boundaries of small-diameter slurr y MTBMs in hard rock are continuously being pushed.

In recent years, the trend towards smaller diameters and longer drives has been increased, which puts a larger focus on the design and selection of efficient MTBM equipment. This does not only ser ve the tunnelling industr y in delivering infrastructural projects in growing South African cities like Johannesburg or Cape Town. Technological advances in tunnelling technologies will also be of great importance to the mining industr y, with impact on the feasibility of future projects and applications.

Water Main Improvement Project, Hong Kong: (A) Job site surroundings, (B) launch shaft, and (C) AVN 800 HR after breakthrough

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LINING SYSTEMS | CORROSION PROTECTION

Unique AKS system keeps concrete protected for longer For reasons of economy, longevity and mouldability, concrete is the structural material of choice for pipes, bunds and reser voirs in wastewater treatment plants.

Supplied in thicknesses from 1.65 mm up to 10 mm, the liner is used in a diverse range of chemically aggressive applications, such as mining, water treatment and the conveyance of sewage.

Its superior crack-bridging ability allows for movement in the concrete structure, without delamination.

AKS™ outperforms

Once anchored firmly into the structure, AKS™ CPL offers a chemically inert, flexible skin

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his versatile and age-old material presents one serious and costly drawback, though: it is susceptible to degradation in modern, aggressive environments.

Corrosion of the concrete due to chemical attack in particular can significantly reduce the lifespan of unprotected concrete structures, such as pipes used in wastewater treatment works. This often necessitates disruptive and costly replacement operations for municipalities and facility operators.

Sophisticated cast-in corrosion protection liners (CPL) such as those manufactured

by AKS Lining Systems effectively prolong the lifespan of new pipes, bund areas and reservoirs, dramatically reducing the lifetime cost.

Groundbreaking advance AKS Lining Systems has taken the cast-in liner concept and perfected its design through the development of Anchor Knob Sheet (AKS™) technology. The concept surpasses all concrete protection alternatives in both cost savings and performance.

46 IMIESA April 2023

AKS™ CPL, manufactured from highdensity polyethylene (HDPE), was designed specifically for the conveyance of sewage and is supplied in wide sheets, tubes or rolls to suit the project requirements.

In the case of concrete piping, the concrete pipe manufacturer integrates the tube with the concrete during the casting process.

The unique anchors are embedded into the concrete, so that the tube forms an integral part throughout the pipe’s length.

In this way, AKS™ enhances the robust qualities of HDPE linings through the close matrix of anchors. These anchors permanently secure the sheeting to the structure.

In its element AKS™ CPL is unique in its design. A total of 1 230 anchors per m² ensure the AKS™ lining is locked firmly into the concrete structure.

The use of HDPE AKS™ CPL in conventional concrete pipes allows these conduits to be used in applications where previously only GRP, PVC or solid wall HDPE pipes would be considered.

A concrete pipe lined with AKS™ offers numerous benefits: chemical resistance to nearly all aggressive environments; no limit to the size or diameter of the pipe; the smooth HDPE internal surface offers far higher friction values for additional carrying capacity; high abrasion resistance ensures minimal damage or wear and tear; and the overall cost of large-diameter pipe lined with AKS™ is greatly reduced compared to alternatives.

Rapid availability AKS™ CPL is manufactured at the large production capacity plant of AKS Lining Systems, based in Brackenfell, Cape Town. A yard with ample storage provides the shortest possible lead times to customers.

For added peace of mind, AKS invites its customers to a plant visit to familiarise themselves with the integrity and quality standards at work at the company.

For fur ther information, please visit www.aks.co.za, email aksmarketing@aks.co.za or call +27 (0)21 983 2700.

STORMWATER & DRAINAGE

Sustainable attenuation pond designs in precast concrete When UD Trucks in Kraaifontein, Western Cape, needed a solution for heavy stormwater flow in an area with a very high water table – during both summer and winter – an attenuation pond was proposed.

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he system developed for this site employs 2 158 Terraforce L11 hollow core concrete retaining blocks purpose-designed for landscaping and erosion control, countering the many pressures working in and around the pond.

A sustainable urban drainage system (SUDS), attenuation ponds are commonly found around new construction projects, such as residential and commercial property developments, as well as new roadways.

“Essentially, the principle is to temporarily store stormwater for phased release back into a watercourse or main stormwater network.

The stormwater is collected and routed into the stormwater system the normal way, but with the use of flow controls,” says Holger Rust, founder and head of Terraforce.

Design layout Terraforce L11 blocks – concrete-filled for this application – were chosen for their weight per square metre to help deal with the surcharge of the parking area, as well as any internal or external water pressure on the pond walls.

The pond was also installed with an impervious plastic lining of 500 micron that comes up 1.2 m behind the Terraforce retaining wall. Any water generated by

ENGEN MBEKWENI CONVENIENCE CENTRE

The Terraforce L12 block and Terracrete permeable paver system installed at the Engen Mbekweni Convenience Centre

PROJECT TEAM

Main contractor: Isipami Construction Civils contractor: Neil Zaaiman Civils Subcontractor: LFC Construction

seepage is taken away immediately by an additional agricultural drain behind the blocks.

To finish off the base of the pond, grass blocks were placed on top of a 250 mm thick drainage layer consisting of a 35% sand and 35% sub-base mix, topped off with 30% clay grit. This special mix provides a solid, but porous base for the pond.

Permeable solution for Engen Demonstrating the flexibility of Terraforce’s systems is another recently completed SUDS project for the Engen Mbekweni Convenience Centre in Wellington, Western Cape. For this project, Terraforce L12 blocks and Terracrete permeable pavers were used to create a naturally draining pond.

UD Trucks Kraaifontein’s attenuation pond lined with 2 158 Terraforce L11 blocks. The pond was also installed with an impervious plastic lining of 500 micron that comes up 1.2 m behind the Terraforce retaining blocks

A single drainage system (pipe, bidim and sand layer) was installed behind the Terraforce retaining wall to catch water ingress and channel it into the main catchment. Gabions were used as stub walls facing the inlets to slow down the flow of stormwater at its peak.

This reduces flow sufficiently to allow it to seep through the large holes of the Terracrete pavers, which are soil-filled to encourage plant growth, further contributing to a reduction in water velocity.

“These projects showcase the effectiveness of environmentally engineered systems to form a diverse range of stormwater interventions. They are vital for combatting erosion, as well as for flood mitigation,” Rust concludes.

UD TRUCKS KRAAIFONTEIN PROJECT TEAM

Consulting engineer: Consulting Engineers Architect: FDA Architects Main contractor: Longworth & Faul Civils contractor: Neil Zaaiman Civils Subcontractor: LFC Construction

IMIESA April 2023

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WATER & WASTEWATER

Urban wetland management is now crucial

Substantial urban green/blue infrastructure has been lost due to urbanisation. Within this class, wetlands have been hit the hardest, as they are highly sensitive ecosystems. Urban wetland management is therefore needed to alleviate the further loss of wetlands.

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he total population of South Africans living in urban areas in 2021 was over 67%. By 2030, the numbers are expected to reach levels of more than 71% and by 2050, eight out of ten people will be residing in urban areas. Due to this rate of urbanisation, there has been an alarming decline in the existence of wetlands. The increased development in catchment areas has led to the increase in wastewater, pollution and pesticides that end up in the wetlands, as well as changes in the landscape and an increase in soil erosion.

Urban wetlands are defined as wetlands that occur in and around urbanised areas; they can be either natural or artificial/ constructed. Whether natural or artificial, they may be permanently or temporarily flooded. Natural wetlands make up lakes, marshes, floodplains, peatland, estuaries, mangroves and coral reefs, while artificial/ constructed wetlands entail ponds, storm water treatment sites, drains, reservoirs and constructed canals.

Urban wetlands are often referred to as the ‘city’s kidney’ or ‘biodiversity library’, due to their ability to purify water passing

FOR MORE INFORMATION ON HOW TO BECOME WATER WISE, VISIT: 48 IMIESA April 2023

through the wetland ecosystem and being a habitat to a vast number of different plant and animal species.

Some of the goods and services provided by urban wetlands include: • Socio-economic benefits to the community, where grass-like plants from the sedge family (bulrushes or Typha capensis) are harvested for making mats, baskets or brooms. Fishing from wetlands can also provide communities with food.

• Recreational, leisure activities are monetised to increase job employment for the communities living in the vicinity of wetlands.

• Their microclimate allows wetlands to reduce overheating in urban areas.

• Wetlands reduce the occurrence of floods in urban areas by reducing the speed/ power of water that enters the wetland ecosystem, and releasing the water slowly into the environment.

• Due to the hydrology, geomorphology and vegetation found in wetlands, the water that enters this ecosystem can be purified through sedimentation that allows particles to settle due to the reduced speed of water.

Also, certain heavy metals can be absorbed

facebook.com/WaterWiseRSA twitter.com/water_wise

by specialised plants within wetlands making them unavailable in the water.

Urban wetland management Urban wetland management is now crucial to alleviate the further loss of wetlands. It is important for any urban wetland management plan to make provision for sustainable development that can be beneficial to both humans and the environment. Urban wetland management strategies should include community projects to promote better management of wetlands, a centralised legal framework that helps protect wetlands, and buy-in from local government to ensure that the green/blue infrastructure is well protected by enforcing the law.

With more than 70% of wetland ecosystem types having no protection in South Africa, this calls for immediate action for wetland conservation, especially as this is a waterscarce country. To make an impact on wetlands in your area, please visit the Water Wise website to see how you can get involved in wetlands conservation.

www.randwater.co.za

www.waterwise.co.za/site/home.html

WATER & WASTEWATER

Closing the gap: access to water In the Eastern Cape and Limpopo, approximately 30% of households have limited access to water, where mostly women and children are required to walk long distances to access water for their basic needs.

SBS Tanks is geared to assist these regions in making water more accessible.

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he provision of safe and readily available water is important for public health and poverty reduction. A recent study by Statistics SA revealed that tap water inside dwellings, off- or on-site, was least common among households in Limpopo (69.4%) and the Eastern Cape (71%).

Alfred Nzo Municipality appointed SBS Tanks to assist with the delivery of bulk water storage solutions. The company installed two 110 000 ℓ steel water storage tanks in the rural area of Luncedweni and a further 120 000 ℓ bulk water storage tank in the Ntabankulu area. The tanks were erected quickly with very little site preparation required and will provide the surrounding communities with water storage for at least the next 65 years.

“SBS Tanks recognises the challenges faced by rural municipalities to deliver equitable access to water across widespread and often inaccessible terrain and within budgetary constraints,” says Mava Gwagwa, director: New Business at SBS Tanks.

Proven, effective solutions “Our solution has been proven to be effective

over the past 25 years and we are geared to assist the Eastern Cape and Limpopo regions, as well as the rest of the country, to bring access to water up to the 100% mark. With our modular, bolted steel panel water tanks and reservoirs, we provide quick access to bulk water storage, at a fraction of the cost, time and infrastructure requirements of a concrete alternative and with the design including a potable water storage liner, it is safer than other steel alternatives.”

According to Gwagwa, the benefit of using a potable-water-safe liner is that water is stored away from direct contact with the tank structure and kept free of contaminants, making it safe for drinking. “SBS Tanks water storage liners are manufactured in our ISO 9001 and ISO 45001 facility and comply with international potable water storage standards, keeping water clean and safe. This is in direct contrast to other bulk water storage solutions, some of which have stored water in direct contact with the welded steel structure, resulting in structural corrosion and contamination of the water. Other storage solutions require water to pass through a treatment plant post storage due to open storage and contact with various other construction materials.”

ABOVE and BELOW Two 110 000 ℓ steel water storage tanks in the rural area of Luncedweni, Eastern Cape

He adds, “The in-house SBS Tanks engineers work with municipal engineers to design the best solution for bulk water or effluent processing. This can include one or multiple SBS Tanks of up to 4.2 Mℓ each to get the necessary configuration and ensure continuous water supply, even during maintenance. Once completed and fitted with liner, the tank can be commissioned immediately and connected to pipework to deliver water to the community.”

For remote sites, SBS Tanks components can be transported in smaller vehicles, or if necessary and in areas with no road access, carried to site. Site preparation requirements include a level platform with safe bearing capacity equal to or exceeding 100 kPa and basic concrete ring beam for larger-capacity tanks, which, along with tank installation, does not require heavy-duty equipment.

Visit the website for more information or email info@sbstanks.co.za for a quote for your next water storage project.

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VEHICLES & EQUIPMENT

BELL CUTS NEW PATH WITH OWN GRADER SERIES

Fitted with the ZF Ergopower transmission, the G140 is well suited for all maintenance and light to medium construction tasks

The introduction of the Bell motor grader series is a significant step forward in Bell Equipment’s strategy to grow its own range of manufactured product for the global construction and mining industries, with production set to begin as early as Q3 2024.

The Bell G200, the largest model in the range, is designed for bulk earthworks and the mining industry

50 IMIESA April 2023

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ell Equipment will initially offer three base machines, comprising the G140, G160 and G200. The G140 is ideally suited for all maintenance and light to medium construction tasks, while the G160, with its increased power and performance, is designed to handle heavy construction applications. In turn, the flagship G200 model is designed for bulk earthworks and the mining industry. Each base machine has the option of a four- or sixwheel drive configuration.

“From the conception of the Bell grader we factored in the requirements of a six-wheel drive configuration. This early integration, as opposed to trying to add into the platform later, has resulted in a better performing machine that is more controllable, robust and easier to maintain,” explains Warren Swart, product manager, Bell Equipment.

VEHICLES & EQUIPMENT

Bell Equipment’s ability to focus on the operator experience and install built-in asset protection is well demonstrated and particularly key to the owners of motor graders.” Warren Swart, product manager, Bell Equipment

Design Over two decades of experience in the supply, maintenance and repair of motor graders – along with insights from many local and international expert advisors – has provided Bell Equipment’s design team with a detailed understanding of optimum machine configuration. While retaining a familiar control and layout, Bell has incorporated a range of advanced components and features that will help operators improve productivity, maintain costs and deliver work efficiently.

Automated functionality for specific tasks has also been one of the significant drivers in the motor grader design process. Automation allows the operator to stay focused on the job at hand. It also helps to improve fuel efficiency and component life expectancy.

Ease of maintenance Recognising the diverse range of applications and often remote deployment of motor graders, Bell has standardised on highquality, low-maintenance components, such as a fully sealed circle bearing. This

provides extended service intervals and consistent grading performance without the need to make regular adjustments. To simplify operations further, advanced diagnostics are incorporated into the machine to reduce the complexity of daily checks and servicing efforts.

Engines and transmissions In terms of the power train, Bell graders are fitted with Cummins engines and ZF transmissions. The G140 uses the Ergopower transmission, while the larger G160 and G200 are equipped with the cPower transmission.

“The Ergopower transmission is well respected in the grading application for entry-level units and we are particularly excited about the opportunity that the cPower transmission provides for higherduty applications. There will be significant advancements that we can offer users of the

Automation has been one of the significant drivers in the Bell motor grader design process

Bell Equipment’s test and prototype graders have already been operating with great success in a wide variety of applications – from landscaping, heavy ripping and final levels to overall road construction

two larger graders by having a transmission that can be so easily tailored to a customer’s needs,” says Swart.

Utilising industry-leading components for all systems has been instrumental in achieving an efficient and robust grader. “Getting established components to work well together is what our system engineers do well and, in a highly operator-sensitive product like a motor grader, we knew that we had to get the overall feel 100% right. We are confident we have achieved this and those testing the product confirmed this for us,” he says.

The Bell design team also focused on providing long-term durability across all structures. According to the results of strain gauge testing, the main frame will provide a life expectancy exceeding market norms by 40%.

Moreover, the tandem axle, with enhanced bearing and interaxle cooling, provides reliable performance in long-haul applications.

“It has been really pleasing to see the improvements in efficiency and performance identified during the design stage being confirmed on real-world job sites,” adds Swart.

Made in SA for the world The Bell grader has been designed as a truly international product with the capability to meet varying emission regulations in international markets, as well as different types of operator controls. The South African launch of this product is only the start of an exciting journey.

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VEHICLES & EQUIPMENT Lu’An Highway Industry’s Lintec CSM4000HRC asphalt mixing plant was retrofitted with Lintec & Linnhoff’s HRC hot recycling system, which allowed 40% of the hot mix asphalt to be derived from RAP

Meeting high production demands, a Lintec CSM4000HRC asphalt mixing plant recently passed the 2 million tonne mark on key road upgrades in China’s Anhui province.

Green asphalt delivery on Chinese expressways

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wned by Lu’An Highway Industr y, the plant set up for the S244 regional expressway project began in Februar y 2016 on a site in Lu’An city, with production commencing the following June, providing hot-mix asphalt for the 23.04 km Huoqiu Garden to Xuji interchange section. The plant produced approximately 150 000 tonnes for the 03 section of the highway, with the project completed in 2022.

Having concluded work on the S244, the equipment has since been used to carr y out asphalt pavement repair and maintenance projects on other

expressways in Anhui province. On these works, the 320 tph capacity Lintec CSM4000HRC plant, paired with its HRC hot recycling system – retrofitted by the OEM – yielded efficient integration of RAP with exceptional productivity.

A key benefit for customers is that the HRC attachment can be retrofitted into any Lintec asphalt plant for the processing of milling waste or material excavated from road pavement recycling, significantly reducing the transport and production costs of bitumen and aggregates.

RAP production During the asphalt production process, RAP materials are first pulverised in an asphalt recycling granulator and then processed and screened into the required sizes. They are then heated inside the HRC’s parallel drum and kept at the optimum temperature

of 140-150°C before being fed into the RAP buffer silo prior to weighing.

By being kept completely separate from the virgin aggregates until mixing begins, the desired amount of RAP can be chosen for each batch. Thereafter, the RAP will join the separately weighed and screened virgin aggregates in the mixer of the asphalt mixing plant to produce a precisely controlled batch of hot mix asphalt.

Commenting on the plant, a spokesperson from Lu’An Highway Industry states: “Over the years, the superb output and quality of our Lintec CSM4000 has been greatly supported by the hot recycling system.

It has given us huge cost savings, while ensuring mix quality remains at the highest level – all while being extremely simple to operate.”

Supplying solutions globally for the asphalt and concrete industries, Lintec & Linnhoff’s comprehensive product line-up comprises the Lintec, Linnhoff and Eurotec brands. Its products include asphalt mixing plants, concrete batching plants, pavement related technologies, and specialist concrete cooling solutions.

Lu’An Highway Industry’s CSM4000HRC plant mixed more than 2 million tonnes of hotmix asphalt for the construction of the 23.04 km S244 expressway and several other road rehabilitation projects in China

52 IMIESA April 2023

CEMENT & CONCRETE

Concrete knowledge vital for safe and reliable infrastructure As concrete is one of the most commonly used materials in construction projects, it is essential that municipal engineers have a strong understanding of its properties and benefits, says Bryan Perrie, CEO of Cement & Concrete SA (CCSA).

material when compared to other construction materials and it can also be produced using locally available materials, reducing transportation costs.

Fire resistance: Concrete is highly resistant to fire, making it ideal for use in structures where fire safety is a concern.

Energy efficiency: Concrete structures have good thermal mass properties, which means they can retain and release heat slowly, leading to substantial energy savings in buildings.

Training courses

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Pigmented concrete lanes forming part of Cape Town’s MyCiTi BRT network

oncrete can be manufactured to an enormous range of specifications to suit a wide variety of applications by using different mix designs or adding different materials,” Perrie explains. This has a bearing in terms of new construction, as well as optimum maintenance interventions to maximise the lifespan of structures and ensure public safety.

Even where old concrete has reached the end of its service life, it can still be reused as aggregate for new concrete mixtures.

Industrial waste by-products that would otherwise have been sent to landfill – like fly ash, silica fume and blast furnace slag – can also be incorporated to enhance the various performance properties of concrete.

“Concrete provides faster construction, which means reduced carrying costs and faster revenue generation. This facilitates more timely payback of financing charges and faster revenue generation for any developer or owner,

including municipalities,” Perrie continues.

Standing the test of time Among the vital qualities of the world’s most popular and perennial building material are: Sustainability: Concrete is a sustainable material that can be produced with lower carbon emissions than other construction materials.

Strength and durability: Concrete is a strong and durable material that can withstand high compressive forces and resist weathering, erosion, and many other adverse environmental factors. This makes it ideal for use in infrastructure that needs to last for many decades.

Cost-efficiency: Concrete is a cost-effective

CCSA’s School of Concrete Technology offers two training courses particularly useful for municipal staff, namely SCT20 Concrete Practice and SCT30 Concrete Technology. Both regularly attract strong enrolment, calling for several presentations every year.

Perrie says the four-day SCT20 Concrete Practice course is excellent for those applying concrete technology on-site such as foremen, supervisors and staff responsible for quality assurance. Additionally, successful completion of this course earns four Continuing Professional Development (CPD) points.

“The more advanced SCT30 Concrete Technology five-day course – which earns five CPD points – is aimed at civil and structural engineers, experienced technicians and technologists, and is ideal for gaining detailed knowledge of how cement and concrete works,” Perrie concludes.

Rome’s ancient Colosseum underscores the longevity of concrete

Iconic architect Santiago Calatrava’s auditorium in Santa Cruz de Tenerife in the Canary Islands strikingly illustrates the design potential of concrete

For further information about the CCSA’s range of services, visit www.cemcon-sa.org.za.

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IMESA MESA

IMESA AFFILIATE MEMBERS PROFESSIONAL AFFILIATES

AECOM siphokuhle.dlamini@aecom.com AFI Consult banie@afri-infra.com Alake Consulting Engineers lunga@alakeconsulting.com ARRB Systems info@arrbsystemssa.com Asla Construction (Pty) Ltd johanv@asla.co.za BMK Group brian@bmkgroup.co.za Bosch Projects (Pty) Ltd mail@boschprojects.co.za BVI Consulting Engineers marketing@bviho.co.za CCG puhumudzo@ccgsytems.co.za / info@ccgsystems.co.za Corrosion Institute of Southern Africa secretary@corrosioninstitute.org.za Dlamindlovu Consulting Engineers & Project Managers info@dlami-ndlovu.co.za EFG Engineers eric@efgeng.co.za Elster Kent Metering Mark.Shamley@Honeywell.com EMS Solutions paul@emssolutions.co.za ERWAT mail@erwat.co.za ESCONGWENI BPH ENGINEERS (PTY) LTD info@escbph.co.za Gabion Baskets mail@gabionbaskets.co.za GIBB marketing@gibb.co.za GIGSA secretary@gigsa.org GLS Consulting info@gls.co.za Gorman Rupp Cordeiro@gormanrupp.co.za Gudunkomo Investments & Consulting info@gudunkomo.co.za Hatch Africa (Pty) Ltd info@hatch.co.za HB Glass Filter Media info@hardybulkinglass.com Herrenknecht schiewe.helene@herrenknecht.de Huber Technology cs@hubersa.com Hydro-comp Enterprises info@edams.co.za Infrachamps Consulting info@infrachamps.co.za INFRATEC info@infratec.co.za IQHINA Consulting Engineers & Project Managers info@iqhina.co.za iX engineers (Pty) Ltd hans.k@ixengineers.co.za JBFE Consulting (Pty) Ltd issie@jbfe.co.za JG Afrika DennyC@jgafrika.com KABE Consulting Engineers info@kabe.co.za Kago Consulting Engineers kagocon@kago.co.za Kantey & Templer (K&T) Consulting Engineers ccherry@ct.kanteys.co.za Kitso Botlhale Consulting Engineers info@kitsobce.co.za KSB Pumps and Valves (Pty) Ltd salesza@ksb.com KUREMA Engineering (Pty) Ltd info@kurema.co.za Lektratek Water general@lwt.co.za Loshini Projects muzi@loshini.co.za Makhaotse Narasimulu & Associates mmakhaotse@mna-sa.co.za Mariswe (Pty) Ltd neshniec@mariswe.com Martin & East gbyron@martin-east.co.za M & C Consulting Engineers (Pty) Ltd info@mcconsulting.co.za Mhiduve adminpotch@mhiduve.co.za MPAMOT (PTY) LTD mpumem@mpamot.com Mvubu Consulting & Project Managers miranda@mvubu.net Nyeleti Consulting naidoot@nyeleti.co.za Odour Engineering Systems mathewc@oes.co.za Prociv Consulting & Projects Management amarunga@prociv.co.za Rainbow Reservoirs quin@rainbowres.com Re-Solve Consulting (Pty) Ltd maura@re-solve.co.za Ribicon Consulting Group (Pty) Ltd info@ribicon.co.za Royal HaskoningDHV francisg@rhdv.com SABITA info@sabita.co.za SAFRIPOL mberry@safripol.com SAGI annette@sagi.co.za SALGA info@salga.org.za SAPPMA admin@sappma.co.za / willem@sappma.co.za SARF administrator@sarf.org.za.co.za SBS Water Systems marketing@sbstanks.co.za Silulumanzi Antoinette.Diphoko@silulumanzi.com Siroccon International (Pty) Ltd admin@siroccon.co.za SiVEST SA info@sivest.co.za Sizabantu Piping Systems (Pty) Ltd proudly@sizabantu.com Siza Water (RF) Pty Ltd PA@sizawater.com Sky High Consulting Engineers (Pty) Ltd info@shconsultong.co.za SKYV Consulting Engineers (Pty) Ltd kamesh@skyv.co.za Smartlock jp.alkema@smartlock.net SMEC capetown@smec.com Southern African Society for Trenchless Technology director@sasst.org.za SRK Consulting jomar@srk.co.za Star Of Life Emergency Trading CC admin@staroflife.co.za TPA Consulting roger@tpa.co.za V3 Consulting Engineers (Pty) Ltd info@v3consulting.co.za VIP Consulting Engineers esme@vipconsulting.co.za VNA info@vnac.co.za Water Institute of Southern Africa wisa@wisa.org.za Wam Technology CC support@wamsys.co.za Wilo South Africa marketingsa@wilo.co.za WRCON ben@wrcon.co.za WRP ronniem@wrp.co.za Zutari Rashree.Maharaj@Zutari.com

CEMENT & CONCRETE

Kariba Dam rehabilitation project progresses

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he stabilisation and reshaping of the plunge pool at the foot of Kariba Dam’s 138 m high wall is using vast quantities of concrete in a range of applications.

“Among the first challenges we faced was in the construction of piers for the temporary coffer dam, where concrete had to be poured underwater to create a foundation,” says Martie Coulson of Mart Martie Coulson, director at Mart Solutions, Chryso Southern Africa’s Solutions, with Gilles Mouquet from Razel Bec Zambian distributor.

Mart Solutions has been one of the key suppliers of construction chemicals to main contractor Razel-Bec since the beginning of the project.

“Difficulties in finding bedrock for piers 7, 8 and 9 – as well as for the dam’s right bank – meant that 22 000 m3 of concrete had to be placed underwater,” Coulson explains.

This arduous process – which took six months and was completed in September 2022 – involved pumping concrete to a depth of 25 m, with divers handling the 125 mm diameter pipe to place the concrete. Adding to the complexity was the movement of water from Zimbabwe’s nearby hydro-electric turbine outlet.

“This raised the risk of the cement being washed out of the mix, leaving the aggregate behind, as well as further reducing visibility for the divers. The Chryso Aquabeton product played a critical role as an anti-washout admixture that increases the cohesion of the concrete mix,” she explains, adding that this allowed the placement of a concrete base for the three piers, measuring some 15 m wide and 20 m deep.

Repairing a rock fault Another important aspect of the project is repairing a fault in the rock at the foot of the Kariba Dam wall.

Here, some 7 071 m3 of specialised concrete will be used for the large 90 m high, 45 m wide and 2.5 m thick wall, which will be built in front of the fault as a protective shield. This will be fixed onto the 12 m long, 40 mm diameter anchors in the wall, which Kariba Dam before and after placement of the piers will in turn be secured 10 m into the rock.

A combination of Chryso Omega 162 and Chryso Fluid Optima 206 will be used in conjunction with densified silica fume and fly ash in the concrete mix for the wall to assist in preventing the temperature rise in the concrete during placement and to avoid cracking. This is important due to the high ambient temperatures of up to 40°C.

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CEMENT & CONCRETE

Desert bridges get extensive overhaul Comprehensive concrete repairs have ensured the continued structural integrity of two strategic bridges on Namibia’s MR44.

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Sikaflex-11 FC+, a one-part, multipurpose elastic adhesive and joint sealant was used on the bridge parapet joints

ocated some 80 km apart, these comprise the Omaruru River Bridge in Henties Bay and the Swakopmund roadover-rail bridge, with refurbishment on both structures completed concurrently by Actual Impact Group. Specialist solutions for all phases were supplied by Sika.

Initial bridge repair work was attained with SikaGrout-212, an easy-to-use, singlecomponent, high-strength, shrinkagecompensated cementitious grout; and Sika MonoTop-412 NFG, an R4 class repair mortar with corrosion inhibitor. On both projects, Sikalastic-152 was also applied to all exposed concrete components, which totalled around 4 450 m2.

Sikalastic-152 is a two-part, cementitious, polymer-modified, flexible, crack-bridging,

based on a combination of epoxy resins and selected high-strength aggregates.

Swakopmund bridge deck About 480 m² of bridge deck and approach slabs at the Swakopmund site had SikaBit Pro P40 PE applied.

Reinforced with a dimensionally stable, non-woven polyester inlay, the underside has a thin polyethylene burn-off film for effortless application. It can be applied to wood, metal and concrete substrates, including over existing bitumen roofing membranes.

On the general concrete work, Sika AnchorFix-2+, a solvent-free, twocomponent anchoring adhesive, was used to anchor the concrete balustrades on the bridges. In turn, Sika Antisol E was used as a concrete curing agent. The latter is a ready-to-use, spray-applied, liquid wax emulsion that prevents water loss from the surface of freshly placed concrete, without affecting the normal setting action.

With the works completed, the bridges are once again ready to withstand the harsh environmental elements on one of Namibia’s most important tourism and commercial corridors.

fibre-reinforced mortar for waterproofing and concrete protection that can be applied to various types of construction substrates. In turn, the expansion joints on both bridges were sealed with the Sikadur-Combiflex SG system.

Both Sikadur-42 ZA and Sikadur-43 ZA were used under the bridge bearing On the general concrete work, Sika AnchorFix-2+, a pads on both solvent-free, two-component anchoring adhesive, was used to anchor the concrete balustrades on the bridges sites. The former is a three-part, moisture-tolerant, multipurpose epoxy grouting system, and the latter a solvent-free, threecomponent, repair and filling mortar

INDEX TO ADVERTISERS 22

Johannesburg Development Agency

16

AKS Lining Systems

OBC

Lintec and Linnhoff Holdings Pte Ltd

2

APE Pumps (Pty) Ltd

OFC, 6 & 13

Mapei South Africa (Pty) Ltd

29

Rand Water

48

Sika

26

Sizabantu Piping Systems (Pty) Ltd

IFC

Specialised Exhibitions (Pty) Ltd / A-OSH

35

AfriSam South Africa (Pty) Ltd

Bell Equipment Group Services (Pty) Ltd

4

BLOC Contractors (Pty) Ltd

39

Blueberry Concepts / IFAT

IBC

DMG Events / The Big 5 Construct South Africa

31

IMESA

56 IMIESA April 2023

9, 44 & 54