The critical role of engineering in waste management
GEOTECHNICAL & ENVIRONMENTAL ENGINEERING
Ground engineering with geo-polymers
RENEWABLE ENERGY & ELECTRIFICATION
Port Alfred’s Nemato UF plant scheduled for PV upgrade
INFORMATION & COMMUNICATIONS
TECHNOLOGY
Client leadership key for BIM adoption
The City of Cape Town’s Dido Valley housing project, supported by Nokhanya Services and AfriSam, is delivering 600 state-subsidised homes including 100 for families displaced from Simon’s Town during the 1960s. Highlighting its focus on restoring communities, beneficiaries were involved in choosing design details to ensure their new homes reflect personal and historical significance. P6
Hands on solutions
EDITOR Alastair Currie
Email: alastair@infraprojects.co.za
DESIGNER Beren Bauermeister
CONTRIBUTORS Francois van Themaat, Geoff Tooley, Ian Venter, Londiwe Mazibuko, Nosiphiwo Rala, Rethabile Shabalala, Richard Matchett, Shaniel Lakhoo
DISTRIBUTION MANAGER Nomsa Masina
DISTRIBUTION COORDINATOR Asha Pursotham
SUBSCRIPTIONS
Email: distribution@infraprojects.co.za
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KEY ACCOUNT MANAGER Joanne Lawrie
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Real collaboration requires transparency and trust
Engagement, collaboration and implementation are words that are commonly underscored in South African public and private sector interactions on effective infrastructure delivery. They are also frequently used when enthusiastically referencing commitment to white papers, municipal and national development plans, Medium Term Development Plans, district development models, and budget promises that often don’t gain the necessary traction despite showing great promise.
overstaffed. In 2020 some 41 787 staff were employed. However, the World Bank’s recommended estimate was around 14 244. If a similar pattern is evident in other SOEs and public departments then there’s a clear opportunity to cut unnecessary costs and invest in high-skilled talent to effect optimum fiscal performance and service delivery.
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.
At times it’s due to political conflict (such as successive mayoral changes during a financial year, or GNU challenges); misalignment between objectives, skills and resources needed for actioning; plus, inadequate funding or the failure to execute available allocations.
Next budget rendition
Given the opposition and debate following the original 2025 Budget Speech in March, the revised rendition presented by South Africa’s Finance Minister Enoch Godongwana on 21st May 2025 is hopefully the one that will now be accepted by all political parties. As Minister Godongwana stated, “It is a reflection of the difficult trade-offs needed to balance fiscal sustainability while addressing our developmental goals.”
It’s plain for all to see that social grants – which account for a sizeable portion of the budget spend – must be enablers and not subsistence handouts. Because grants must move impoverished and unemployed people into jobs and adequately serviced housing.
Hopefully the R1 trillion allocated for critical infrastructure over the next three financial years – commencing from 2025/2026 – will achieve this while ensuring that the broader macroeconomy flourishes.
Allied to this, in the May 2025 budget speech there’s a renewed emphasis on reducing public debt and improving overall governmental efficiencies to help steer the country towards a conservative Gross Domestic Product improvement. This is expected to reach just 1,8% in 2027.
Human capital needs audits
From a country perspective, the tough decisions required to achieve positive gains should include a human capital needs audit and rightsizing analysis across all government departments. Just as private sector companies must constantly reposition and rightsize to evolve in our competitive high-tech world, so too must public entities.
For example, a World Bank analysis of Eskom’s personnel requirements in 2020 showed that the SOE was heavily
For the private sector, the primary requirement is a faster move to free market reform because overregulation has been flagged by local and international investors as a major disincentive. A positive step in this direction are the new regulations gazetted for public-private partnerships (PPPs), effective June 2025. These regulations are meant to simplify PPP deal processes and speed up approvals for vital projects inside and outside the infrastructure space.
Technologies that are cheaper and enabled in other developed and developing countries – like satellite telecommunications services and free citywide WiFi – must also be introduced locally to boost SME growth and youth employment. Currently, South Africa is one of the most expensive cellular markets, which contributes to digital exclusion.
Operation Vulindlela Phase II
Within the current policy mix is Operation Vulindlela Phase II, launched in May 2025 and designed to speed up policy enabling objectives. This initiative builds on Phase I, which commenced in October 2020. A key Phase II objective is improving local government performance. Part of this process includes a current review of the 1998 White Paper on Local Government. The review, released on 10th April 2025, homes in on nine policy priority areas that include the depoliticisation of municipal administration. Going forward, our ultimate goal as a country is to have equivalent skills and experience mirrored at professional and leadership levels in both the public and private sector. Just as any listed private entity needs to have a coherent and workable business plan to keep shareholders on board, the same applies to public entities in terms of voter engagement.
Money talks and actions speak louder than words. Therefore, all decision-makers – public and private – must be equally participative in reengineering an empowered and unified South Africa.
It’s no coincidence that top performing municipalities employ best-in-class expertise, whether it be administrative, IT, financial or engineering. They also tend to operate in a supportive, politically aligned environment that provides a collaborative culture geared towards service delivery.
These municipalities also comply fully with the myriad and often complex legislation required to manage their operations effectively in areas like electricity, water and wastewater provision and billing.
Although past Auditor-General South Africa reports on local government outcomes do paint a mixed picture in terms performance and underperformance (and too much of the latter), they also emphasise that there are pockets of excellence. Plus, there has been a progressive improvement in the percentage of municipalities transitioning towards a clean audit without findings. This is an important observation because we need to eliminate negative perceptions that there is a general state of chaos. There are many examples of exceptional infrastructure execution across the country. Plus, South Africans in our main centres are now generally better serviced today than they were 30 years ago. However, this doesn’t ignore the fact that improvements are needed in many areas, particularly in terms of sustainable asset management and environmentally compliant infrastructure.
Stretched to the limit
At present, many municipalities – particularly smaller ones – fall short of infrastructure performance benchmarks because they are heavily understaffed. In this scenario, municipal engineers are often forced to wear too many hats in simultaneously addressing multiple requirements such as roads, water, wastewater, and landfill management. It’s a highly onerous task that inevitably impacts on optimum results.
Part of the solution has been to rely increasingly on the consulting engineering sector to supplement and/or boost capacity. Longer-term, however, this is not sustainable at current levels. While consulting engineers are essential for the provision of specialist design services and the application of new technologies, they are not meant to supplement or replace municipal in-house
RECOGNISING EXCELLENCE
Municipal engineering is the foundation for socio-economic growth
capacity. Professionally registered municipal engineers must be equipped and able to run their own maintenance and construction projects, and then to determine when and where consulting services will add value.
Numbers and Needs
A key starting point in building current and future capacity is to obtain an accurate picture of the current number of practicing engineers, technologists, and technicians. Then we need to factor in future infrastructure requirements in line with population and urban growth projections. This will help determine how many future engineering graduates we need annually, and in what disciplines.
Past research by Dr Allyson Lawless – an exSAICE President and accomplished professional engineer – have been instrumental in identifying the skills and experience gaps. For example, her “Numbers and Needs” publication series are definitive works, and include “Numbers and Needs in Local Government,” released around 2007.
At the time, the latter revealed that “the civil engineering capacity in South African municipalities was too low to deliver, operate and maintain local government infrastructure in a sustainable manner.” Fast forward to 2025 and the situation has worsened. For example, some local municipalities currently don’t have any inhouse engineering personnel.
From IMESA’s standpoint, we are investigating how we can roll-out new funded research within the municipal engineering sector, so we know where we need to be in 10-, 20- and 30-years’ time.
Professionalisation, career and skills development
To effect meaningful change, there needs to be a renewed focus on professionalisation, talent
Geoff Tooley, Pr Eng Hon FIMESA IMESA President: 2024-2026
retention, training, and recruitment. In this respect, it’s vital that young engineers recognise the value of a career in the public sector, where there are real-world opportunities to effect innovation.
As IMESA we strive to achieve this through our ongoing university outreach programmes. In parallel, we support candidate engineers through to professional registration via comprehensive mentorship programmes. Then from a CPD perspective, we host training workshops nationally on various technical plus related non-technical subjects, as well as showcasing examples of outstanding municipal infrastructure works via regional site visits to foster knowledge transfer.
That’s also a key motivation for our biennial IMESA/CESA Excellence Awards, with this year’s event coinciding with the 88th IMESA Conference taking place between 29th and 31st October 2025 at the East London International Convention Centre. The deadline for IMESA/CESA Excellence Awards project submissions is 3rd July 2025.
Record number of conference abstract entries
For the 88th IMESA Conference, the Call for Abstracts closed on 17th April 2025, and we received more than 100 submissions. These are currently being reviewed by IMESA’s Technical Advisory Committee and successful applicants will be informed shortly based on the selection criteria, namely innovation, thought leadership, business value and interest, as well as conformance to this year’s conference theme, which is “Sustainable
Our last IMESA conference in East London was held in 2016 and hosted around 900 delegates. Based on the current uptake, the 2025 conference looks set to equal or exceed this number. Our ultimate objective is to have all South African municipalities represented because that will signal a renewed commitment to universal municipal engineering excellence.
Nokhanya Services has given momentum to a transformational housing project in Dido Valley near Simon’s Town
NOKHANYA SERVICES AND AFRISAM PUT QUALITY FIRST AT DIDO VALLEY
With its important land restitution component, the City of Cape Town’s Dido Valley housing project near Simon’s Town on the Cape Peninsula has been solidly progressed by contractor Nokhanya Services and construction materials leader AfriSam.
The overall project comprises 600 Breaking New Ground (BNG) state-subsidised houses, with 100 allocated to land restitution claims – relating to the forced removals of families from Simon’s Town in the 1960s. Nokhanya Services spent a year on-site completing their portion of the project between 2022 and 2023.
“This is not just a normal local housing project; it’s about redressing historical injustices and restoring communities to the areas from which their ancestors were
The overall project comprises of 600 Breaking New Ground (BNG) state-subsidised houses, with 100 allocated to land restitution claims
displaced,” says Faith Mabena, Owner and Director of Nokhanya Services. “It was crucial to uphold standards and the finishing touches reflect the commitment. Beneficiaries were consulted on personal design elements such as awnings, tiles and paint colours to make their homes genuinely feel like their own.”
AfriSam contributed its own quality focus to the project, regularly testing its readymix concrete and other materials as part of its standard quality control procedures, according to Bradley Thomas, Territory
Sales Manager for AfriSam. More than this, AfriSam also took regular test results from the site, giving the contractor and end-client detailed confirmation of concrete quality and specifications pertaining to the approved mix designs.
“We sampled every major pour to guarantee the integrity of the concrete, meeting the stringent standards set by the city,” says Thomas. This meant having AfriSam’s technical laboratory on site and ready for the readymix truck’s arrival so that samples could be taken and the tests conducted.
Terrain challenges
The building process in Dido Valley presented a few hurdles, according to Mabena. The site’s mountainous terrain, for instance, led to design adjustments and extensive groundwork for some foundations to ensure structural integrity.
1 Nokhanya Services collaborated with experienced subcontracting teams to transfer skills and maintain quality
2 Beneficiaries were consulted on personal design elements to make their home to genuinely feel like their own
3 AfriSam supplied 2 500 m3 of readymix concrete, two thousand bags of AfriSam All Purpose Cement as well as 10 mm aggregate stone to the project 1 2 3
“Engineers had to modify plans in areas with significant soil erosion,” she explains. “The supply chain also had to be carefully managed to keep everything on schedule, as there were items like precast slabs for double story units which had to be manufactured in advance.”
Local economic empowerment was integral to the project, with Nokhanya Services blending their trusted Cape Town subcontractors with workers from Redhill township close to Simon’s Town.
“We collaborated with our experienced subcontracting teams to transfer skills and maintain quality,” Mabena says. “This approach allowed us to contribute to upskilling of less experienced workers, thereby fostering job creation in the local economy.”
Best-in-class logistics
She noted that AfriSam’s role has been
critical – providing readymix concrete, cement and logistical support. According to Thomas, about 2 500 m3 of readymix was delivered to the site, mainly for foundations. Two thousand bags of AfriSam All Purpose Cement were also delivered, for bricklaying, plastering and other work.
“We also supplied the 10 mm aggregate stone which was used by the manufacturers of the precast slabs,” he notes. “Among the logistical site challenges at Dido Valley were the steep gradients, so we reduced truck loads slightly to reduce the risk of spillages on public roads. This is in keeping with our commitment to a clean environment.”
Readymix could be dispatched from AfriSam’s City plant in Woodstock and from its Philippi plant, depending on traffic conditions.
With the Dido Valley site some 45 km from the plants, the concrete mix included the necessary admixtures to extend the concrete’s design span, normally three hours before setting.
“We monitored traffic patterns to check which plant would be able to deliver the readymix quicker,” he says. “We are always aware that the timeous arrival and placement of our readymix is vital to the scheduling of on-site work.”
A successful partnership
Thomas says the careful planning and frequent communication between AfriSam and Nokhanya Services’ trained site staff made for a successful partnership in this project. This was made more difficult by an unusual challenge – no cellular phone signal on site.
Mabena emphasises how quality control is central to risk management for Nokhanya Services and their clients, ensuring both reliability and excellence in project delivery.
“Collaborating on the Dido Valley housing project with a trusted partner like AfriSam gave me the reassurance that high quality products were used with the necessary controls,” she says.
“This not only ensures value for money for my clients but also safeguards my reputation as a responsible and ethical contractor,” Mabena concludes.
THE GUARDIANS OF INFRASTRUCTURE VALUE AND ACCOUNTABILITY
Keeping construction projects on track, within specification and on budget are among the core roles performed by quantity surveyors (QSs), helping to ensure that clients get the best return on investment. IMIESA speaks to Nolubabalo Tsolo, Executive Director, Association of South African Quantity Surveyors (ASAQS) about the profession’s evolving mandate, and the need for greater representation within the public and private sector.
In terms of the Quantity Surveying Profession Act 2000, what work is specifically reserved for registered PrQS practitioners?
Under Section 26 of the Quantity Surveying Profession Act (Act 49 of 2000) and the SACQSP Identification of Work (IDoW) policy, only registered Professional Quantity Surveyors (PrQSs) may perform the following identified and reserved work:
• Preparation of bills of quantities, elemental cost estimates, financial feasibility reports, and tender documentation.
• Management of payment certifications, contractual valuations, and final accounts.
• Providing contractual, procurement and cost advice, including lifecycle costing, value engineering, and sustainability assessments.
• Acting as Principal Agent or Principal Consultant under a construction contract.
• Engaging in risk management, dispute resolution, and financial control systems.
Do all construction projects require a QS?
Not by law, but any project involving financial and contractual complexity should include a QS. As outlined in Section 4.1 of the IDoW, QS professionals are trained to navigate the entire value chain of a construction project – from inception to close-out – ensuring that costs are realistic, traceable, and defensible.
ASAQS believes every infrastructure investment, particularly in the public sector, should include a registered QS to support compliance with the Public Finance Management Act (PFMA), Municipal Finance Management Act (MFMA), and SACQSP registration requirements.
Within South Africa, are there evolving synergies between QS practitioners and Chartered/Land Surveyors?
Yes. The constructive interaction is evolving due to advances in technology and data integration. QS professionals are collaborating more with land and chartered surveyors in areas like:
Construction measurement alignment
• GIS integration for infrastructure mapping Development planning using drone and terrain data, and
Land value estimation for feasibility studies. While the scopes are distinct, overlaps noted in the IDoW and CBE’s framework are
resolved through professional protocols. SACQSP encourages registration for anyone practising within the QS scope.
Within the public sector environment, what is the estimated number of QS practitioners employed?
Based on ASAQS and SACQSP's internal data, approximately 800 to 1 200 QS professionals are active in public sector roles, including departments such as Public Works, Human Settlements, Education, and Health, as well as municipalities and SOEs.
This number is insufficient for the scale of infrastructure rollouts. ASAQS advocates increasing intake and retention of QS graduates in the public service, aligned with IDoW requirements.
Should municipalities focus on recruiting more in-house QS personnel or rather outsource this function?
Municipalities need in-house PrQSs to uphold governance, interpret audit outcomes, and ensure IDoW-compliant practices. However, outsourcing remains essential for peak workloads or specialised services.
The IDoW policy prohibits unregistered persons from performing identified QS work unless under the supervision of a registered PrQS, making in-house capacity vital for compliance and sustainable infrastructure delivery.
When it comes to auditing, and more specifically Auditor-General SA (AGSA) outcomes, should QS
Nolubabalo Tsolo, Executive Director, Association of South African Quantity Surveyors (ASAQS)
practitioners involved on specific infrastructure projects be held accountable for supply chain irregularities?
The SACQSP Code of Conduct binds registered PrQS practitioners, and under Section 27 of the Act, improper conduct includes negligence, false certification, or complicity in irregular practices.
However, QSs should only be held accountable within their professional scope. ASAQS supports greater role clarity and is working with AGSA to ensure that QS professionals are included in audit processes, not scapegoated, and that IDoW-aligned roles are respected.
How is the Building Information Modelling (BIM) environment influencing and enhancing QS functions and services?
BIM is significantly transforming the QS profession by enabling:
• Automated quantity take-offs and 5D cost modelling
• Scenario analysis for sustainability and material choices
• Improved collaboration with other consultants in real-time.
ASAQS is actively upskilling members through EduTech CPD programmes and advocating for the adoption of BIM in government infrastructure.
Can QS practitioners add value in terms of sustainable design interventions and optimum lifecycle/asset management return on investment (ROI)?
Absolutely. As the IDoW outlines, registered QSs are key to:
• Performing lifecycle costing
• Advising on material sustainability trade-offs
• Auditing asset performance and maintenance costs, and
• Supporting green building rating strategies (e.g. GBCSA).
ASAQS is working on lifecycle ROI models that integrate cost, carbon, and social value, ensuring the QS’s value in sustainable infrastructure is quantifiable and impactful.
What are some of ASAQS’s key objectives over the next 18 months?
One of ASAQS’s key strategic objectives over the next 18 months is to promote a
culture of accountability, ethical conduct, and professional integrity across the quantity surveying industry.
For external stakeholders, this translates into:
• Greater trust and credibility when engaging with ASAQS-affiliated professionals.
• A clear framework for ethical conduct and dispute resolution, boosting confidence in project transparency and professionalism.
• Assurance that ASAQS professionals operate under strong governance standards aligned with national and international expectations.
• A reaffirmation of ASAQS’s commitment to safeguarding the value of public funds, ensuring that infrastructure is delivered ethically and responsibly.
Quantity surveyors are more than cost managers, they are guardians of infrastructure value, ethics, and accountability.
As ASAQS, in partnership with SACQSP and CBE, we are committed to ensuring that the quantity surveying profession continues to evolve, lead, and deliver. Through digital innovation, international expansion, ethical leadership, and firm regulatory grounding, we invite the built environment to truly “Experience the Value” of a profession that is purposedriven, future-ready, and deeply essential.
MUNICIPAL LIABILITY AND THE HIDDEN DANGERS BENEATH OUR FEET MIND THE GAP
A recent High Court judgment (Yende v City of Johannesburg Metropolitan Municipality and Another) offers important insights into the evolving jurisprudence on municipal liability for injuries caused by defective public infrastructure. The case highlights how courts weigh the public's right to safe infrastructure against the operational constraints faced by municipalities. By
Rethabile Shabalala, Nosiphiwo Rala and Londiwe Mazibuko
The plaintiff sustained injuries after falling into an uncovered stormwater manhole on Chris Hani Road, Soweto, while walking to catch a taxi. She suffered a fractured right ankle, which required surgery, and an extended hospital stay. The matter proceeded on the issue of liability only, with damages (quantum) to be determined at a later stage.
The plaintiff’s claim was based on negligence, which required her to prove all the elements of negligence on a balance of probabilities.
In response, the defendants denied any legal duty to maintain the manhole. Alternatively, they argued that if such a duty did exist, it was subject to the limitations of manpower and available resources.
The plaintiff's evidence confirmed that the incident occurred during the day. She conceded that she had been multitasking, walking briskly
while looking for a taxi. The defendants led evidence that the Johannesburg Roads Agency (JRA) had both proactive and reactive maintenance plans for manholes. The JRA also reported limited resources and relies on members of the public to report infrastructure defects. Manhole covers, according to the evidence, are inspected twice a year.
The court acknowledged that a municipality’s legal duty is not absolute and must be assessed in light of its capacity, particularly funding and staffing. However, it found that the defendants had conceded the legal duty to cover and barricade manholes, and were negligent in fulfilling this duty. A reasonable person in the position of the JRA would have taken proactive, reasonable steps to prevent harm, particularly on a road with high pedestrian traffic such as Chris Hani Road, where the risk of injury was foreseeable.
Insofar as the defence based on manpower and resources was concerned, the court was unable to consider it, as it had not been put to the plaintiff and no supporting documentary evidence had been discovered.
The court held the defendants liable to the plaintiff. However, it also found that the plaintiff had contributed to the incident. Given her own admission that she had been walking briskly and multitasking, and taking into account the clear weather and unobstructed pavement, the court concluded that she had failed to keep a proper lookout. She was found to be contributorily negligent. The court therefore apportioned liability, holding the defendants jointly and severally liable for 50% of the plaintiff’s proven or agreed damages. This judgment confirms that there is no blanket liability for municipalities in cases involving defective infrastructure. Each case must be considered on its own facts. Plaintiffs are also expected to take reasonable care for their own safety.
Importantly, where relevant and properly presented, evidence of a municipality's budgetary or resource constraints may help displace a finding of negligence and causation.
Key takeaways for both the public and municipalities include:
• Municipalities have a legal duty to take reasonable, proactive steps to ensure the safety of public infrastructure, especially in high foot traffic areas.
• This duty is not absolute and must be evaluated in light of available resources, but municipalities must produce credible evidence to support any limitation.
• A failure to act, even in the absence of an absolute duty, may still amount to wrongful and negligent conduct where the risk of harm is foreseeable.
• Contributory negligence remains an important consideration; members of the public also have a duty to take reasonable care for their own safety.
Rethabile Shabalala, Senior Associate at Webber Wentzel
Nosiphiwo Rala, Trainee Attorney at Webber Wentzel
Londiwe Mazibuko, Candidate Attorney at Webber Wentzel
Preparing your kikuyu lawn for winter A water-wise guide
In the month of May, it's important to begin preparing your kikuyu lawn for its natural winter dormancy – an environmentally responsible choice, especially in water-scarce regions such as South Africa. Embracing this seasonal rest period is not only practical but also helps conserve water.
Your grass can enter a state of graceful dormancy without needing to be over watered if you recognise and honour its natural cycles. Here Water Wise explains how one can maintain their kikuyu lawn during the winter season while using much less water, building resilience, and making sure it returns to life and vigorous growth in the spring season.
Kikuyu
Pennisetum clandestinum, commonly known as kikuyu, is the most widely used lawn grass in South Africa. It is native to east Africa and has an aggressive growth form, which means it can become invasive and take over indigenous grasses.
Kikuyu is drought tolerant, inexpensive, and easy to maintain because it can grow in areas where most grasses cannot. However, it is sometimes considered the highest user of water in comparison to other commonly used turf grasses.
Kikuyu is mostly planted as an instant lawn for sports fields, golf course construction, and
rehabilitation. It has a mat root and herbaceous growth habit. It however doesn’t grow well in shaded areas.
Dormancy in lawn
Dormancy refers to a period where growth of the grass temporarily slows down, and grass goes into a resting state for one season. Kikuyu in nature always goes dormant during winter, where the grass will turn brown. However, brown kikuyu grass does not mean it is dead; it has simply gone dormant.
Lawn in a state of dormancy is simply “resting” and conserving energy for the new growing season. Dormancy is a natural way for lawn to conserve moisture and nutrients in cold and dry seasons. It is therefore not necessary to apply a lot of water to your kikuyu during winter.
Water-wise watering of kikuyu
• Avoid frequent watering of kikuyu when it is dormant.
• Check your lawn in the morning to assess moisture levels. If it seems moist, water once every 14 days depending on the weather.
• When the lawn appears to be dry, apply deep watering once a week and only water in the morning (between 6 am – 10 am) until optimal moisture is reached.
• Avoid watering in the evening to prevent prolonged moisture on the grass, which can lead to fungal diseases.
• Newly installed kikuyu will only require more water during its settling or establishment period. Gradually decrease the frequency of watering after this phase.
• In summer, water in the early morning or late afternoon as this reduces water lost to evaporation.
• Use a trigger nozzle if watering kikuyu with a hose.
Smart maintenance of kikuyu
• Stop mowing your lawn; with reduced grass growth in winter, longer blades insulate roots and soil from cold temperatures while roots remain active.
• Only apply organic fertiliser as part of your spring treatment towards the growing season.
• As spring approaches, prepare for weed emergence on your lawn by hand-picking or spot-treating weeds with organic herbicides.
This article was co-authored by Rand WaterWater Wise and Evergreen Turf, aiming to raise awareness among the public and customers about sustainable practices for watering and maintaining kikuyu lawns.
Always Be #WaterWise
www.randwater.co.za 0860 10 10 60
Summer versus winter
THE CRITICAL ROLE OF ENGINEERING IN WASTE MANAGEMENT
With more and more waste generated due to growing and evolving economies, engineering in waste management is not just a supporting function – it is the cornerstone of environmental protection, operational safety, and long-term sustainability.
EnviroServ, a SUEZ company, maintain that engineering impacts every area of waste management and that it plays an important role in their compliance. “The integrity of a green landfill system requires precise design and engineering, not only to protect the environment but also to ensure compliance,” says Nico Vermeulen, Operations Director at EnviroServ.
EnviroServ takes this responsibility seriously, ensuring that, when designing their waste management facilities, every aspect of the design and operation is underpinned by solid, science-based engineering principles.
“It’s not just about protecting the environment,” says Vermeulen. “You’re managing complex interactions between materials – from HDPE liners and clay to leachate chemistry and stability factors. If these aren’t carefully calculated and executed, you risk system failure, environmental contamination, and long-term liability.”
Liner systems: The foundation of environmental protection
A waste management facility or green landfill’s liner system is its first line of defence against groundwater contamination. Proper design ensures that HDPE liners, clay layers, and drainage systems interact correctly. An essential
part of this is preventing indentations or damage to liners from overlying stone, which can lead to cracks over time. Structural stability must also be ensured to avoid future landfill slope failures, particularly at smooth slip interfaces like those between plastic liners and clay.
“Compatibility is critical,” Vermeulen explains. “You can’t use just any material – the materials used must be resistant to chemical attack and be physically robust enough to last decades.”
Beyond material selection, landfill stability must be considered. Smooth surfaces, like HDPE, can create potential slip planes where
Managing water effectively is a crucial aspect of landfill design, factoring in rainwater, groundwater, and surface water elements
waste may shift – particularly under heavy rainfall or poor compaction. This requires stability modelling to ensure safe long-term performance.
“You want to design the liner system so that if any movement occurs, it happens in a controlled and predictable layer – not through your clay or core containment structures,” says Vermeulen. “It’s about creating engineered resilience.”
Drainage design:
Managing liquids effectively
Effective leachate and stormwater drainage is another critical engineering challenge. Drainage systems must be correctly sloped and sized to ensure the uninterrupted flow of leachate, with built-in redundancy for system resilience.
In parallel, surface water management is essential to prevent clean rainwater from mixing with waste. The goal, Vermeulen explains, is to keep clean water clean – by diverting it away from active waste zones and capturing only what is necessary.
“Rainwater that falls directly onto waste becomes leachate – a highly contaminated by-product that’s difficult and costly to manage,” he notes. “We aim to minimise this by ensuring efficient runoff and containment systems, including contaminated stormwater dams. Water can be reused for dust suppression and other on-site needs.”
Moreover, engineering in waste management extends to managing rainwater, groundwater, and surface water. Clean water must be kept uncontaminated through diversion and containment strategies.
Landfill liner systems are the foundation of environmental protection
Gas management systems, including flares, must be properly engineered to optimise gas capture and destruction
Gas capture and flaring: Engineering for sustainability
Landfill gas is both a challenge and an opportunity. If unmanaged, methane emissions pose a serious greenhouse gas threat. However, with the right gas extraction systems in place –including flaring – landfill gas can be captured and destroyed safely.
“Installing flare systems is part of being a responsible operator,” says Vermeulen. “But it’s not just about putting a pipe in the ground. You need proper spacing of wells, correct sealing, and pipe slopes that avoid condensation buildup, which can block flows.”
System balance is essential. Over-extraction can dilute gas quality, while under-extraction
allows methane to escape. Continuous monitoring ensures that the volume extracted matches the methane being generated.
“You want a constant, stable supply of gas that can be properly combusted at high temperatures, ensuring full destruction of harmful components,” Vermeulen adds. Gas management systems, including flares, must be properly engineered to optimise gas capture and destruction.
Engineering for people and the future
Beyond environmental protection, engineering must also safeguard people. This means designing site layouts that protect workers, and other stakeholders from exposure, heat, and other risks, and maintaining high safety standards.
“I take my hat off to employees who work at the sites on a daily basis,” Vermeulen says. “As engineers and leaders though, it’s our job to ensure those conditions are managed as safely and responsibly as possible.”
Conclusion
From liner design and material compatibility to stormwater diversion and landfill gas management, modern landfill engineering
A key aspect of landfill design and management are safe site layouts that protect workers, and safeguard communities
is a complex discipline that requires precision, foresight, and a deep understanding of environmental science. At EnviroServ, engineering is not just a function – it’s a commitment to doing things right, for the environment, for communities, and for the future of sustainable waste management.
MINING | INDUSTRY | MUNICIPAL | AGRICULTURE | FOOD AND BEVERAGE | FIRE FIGHTING
GROUND ENGINEERING WITH GEO-POLYMERS LEVELS ANY STRUCTURE 1
Founded in Finland in 1977, Uretek’s invention of the slab lifting method set a new benchmark for ground improvement solutions. This was subsequently followed by the patented Uretek Deep Injection® (UDI) process developed by Uretek in Italy. IMIESA speaks to Tony Pappalardo, managing director at Uretek Geo Systems – Uretek’s licenced contractor for Southern Africa – about the technological advantages for remediating subsidence issues and improving soil integrity on brownfield and greenfield structures.
Essentially, the UDI approach employs a series of purposedeveloped geo-polymers (resins) to provide a non-disruptive, efficient and fast solution to increase the loading on sub-standard soils, as well as to counter subsidence issues on buildings and concrete foundations ranging from harbour quay walls to airport aprons and bridges, with minimal environmental impact,” explains Pappalardo, adding that the two key focus areas are surface consolidation and at depth consolidation.
For surface consolidation projects, the specified resin is injected at various points into the shallow area beneath the foundation. The process reestablishes contact between
the underside of the foundation and the underlying soils by filling any voiding within the treated soil as the pumped resin transitions from a liquid to a solid state via polymerisation. As the name implies, at depth consolidation adopts a similar approach, but at greater depth intervals.
Zone of influence
Typically, each injection point will create a zone of influence of approximately 1 m radius (depending on the characteristics of the resin utilised), resulting in a section of reinforced soil. Drilled injection points are usually placed at 1 to 1,5 m centres, with tubes then inserted to enable the pumping of the resin. However, Pappalardo says the spacing can
be altered depending upon factors such as soil type, soil strength and loading.
Once injected, the resin expands horizontally and vertically, following the path of least resistance, targeting areas with the greatest need for reinforcement. Thereafter, the resin expands vertically. For subsidence remediation, this steady pressure on the underside of the foundation progressively lifts it back into its original position.
Precision control and laser monitoring
Throughout the geo-polymer injection process, relevant parts of the overlying structure are monitored using rotary lasers and mounted sensors placed in the vicinity of the active injection points. Each injection will be prolonged until a reaction is registered (< 0,5 mm). This indicates when a degree of compaction/consolidation has been achieved. It also confirms that the treated soil has been reinforced sufficiently to carry the load of the structure.
FOUNDRY RECLAMATION PIT PROJECT
1 Holes were drilled in the concrete slab to the predetermined depths followed by the installation of injection tubes to form a resin-impregnated curtain wall around the subsequent excavation for the foundry reclamation pit
2 With the geo-polymer curtain wall established, the contractor then cut and removed the concrete floor slab section and employed a mini excavator to complete the excavation
3 Despite the unexpected encounter of groundwater below 3,5 m, the curtain wall remained secure. Side supports were installed as a precautionary measure
4 The injected geo-polymer follows the path of least resistance, filling voids and strengthening the soil’s overall load bearing capacity
“The rate of expansion is determined by the specific geo-polymer employed, as each project has its own unique requirements,” says Pappalardo. “Factors to consider include resin density, required compressive strength, and the timeframe for the beginning and end of the expansive phase. Once all injection stages have been completed, the resin impregnated ground is virtually impermeable.”
Before each project begins, comprehensive Dynamic Cone Penetrometer (DCP) testing is conducted, along with a Standard Penetration Test (SPT) to determine the soil shear strength values at the predetermined depths and the required bearing capacity. Then on completion of the project, a further DCP test is carried out to verify the increase in soil strength achieved. Completed works can also be verified using a number of different testing methods, including plate load testing, CBR testing and GPR surveys, depending upon the client’s requirements. In some cases, Uretek’s projects have increased the bearing capacity by up to 300%.
Case study: soil stabilisation for a foundry reclamation pit
A recent project completed by Uretek Geo Systems for an industrial client in Isando, Gauteng underscores the practicality and efficiency of geo-polymer injection soil stabilisation techniques.
Uretek Geo Systems was contacted by MCB Ningi Consulting Engineers to provide a ground stabilisation solution for the construction of a 4 m x 4 m x 4,5 m deep reclamation pit to be excavated within a fully operational foundry. The purpose of the reclamation pit is to store used foundry sand for subsequent reprocessing and reuse in casting operations. Due to the unknown nature of the subsoil beneath the foundry floor where the pit was to be established, concerns were raised about the potential collapse of the pit’s sidewalls during excavation. A reliable solution was required to prevent soil failure, while ensuring minimal disruption to foundry operations during construction within a confined working space.
2 3 4
DCP tests conducted prior to excavation revealed soft to very soft material up to a depth of 3,2 m, posing a high risk of collapse. However, stiffer material encountered below 3,2 m provided better natural stability.
Further complicating matters, the pit site was located near the foundry’s shaker, a machine that generates constant vibration as it separates completed castings from the moulding sand post-production. This presented a further challenge in terms of maintaining excavation stability.
To reinforce the surrounding soil and to prevent collapse, Uretek proposed a geo-polymer injection process to create a
stabilising curtain around the excavation area. The plan involved:
- Injecting Uretek polymer 400 mm behind the edge of the pit before excavation.
- Creating a reinforced soil curtain that would strengthen the material and prevent sidewall collapse.
- Utilising a two-row injection system for optimised consolidation. The first row comprised four injection points per side at 1 m intervals, injecting at -3 m, -2 m, - 1m and 500 mm below the slab. Positioned 300 mm behind the first row, the second row (staggered), entailed injecting at -2 m and -1 m.
This methodology would pre-compact the soil, improve its load bearing capacity, and enhance overall stability before excavation.
With the plan approved, the stabilisation works commenced and were completed over
two days. The first day entailed drilling to the predetermined depths followed by injection tube installation. This was followed the next day by injecting the expanding geo-polymer in a controlled manner, filling voids and consolidating the surrounding soil. Laser monitoring ensured precise resin expansion and soil strengthening.
With Uretek’s scope completed, the contractor then cut and removed the concrete floor slab section over the designated site on the third day and excavation commenced, using a mini excavator lowered into the deepening pit.
“As the excavation progressed below 3,5 m, groundwater intrusion occurred, which had not been anticipated. This introduced an additional risk of soil loosening and collapse. In response, side supports were installed within the excavation as a precautionary measure to
WAREHOUSE PROJECT: PRECAST COLUMN REALIGNMENT
During a series of warehouse developments, the contractor discovered that some of the precast columns installed (varying in height from 12 to 14 m) to support the roof trusses were off-vertical within their cast in-situ concrete 2,5 x 3,5 m bases. For each affected column, Uretek’s team injected geo-polymer into the base on the leaning side to push them into their correct vertical alignment
mitigate potential soil instability, with pumps utilised to remove water seepage,” explains Pappalardo.
“Throughout the final excavation process, the works continued seamlessly without incident, thanks to our reinforced soil curtain, effectively mitigating any potential sidewall collapse within a challenging construction environment. Plus, the foundry’s shaker machine continued to operate without any downside impact.”
Comments Mark Woods, Director at MCB Ningi Consulting Engineers: “Historically Uretek has assisted us on several projects, including stabilisation of a deep fill terrace below an existing shopping centre to arrest long-term settlement that had occurred and enable successful crack damage repairs to take place. Uretek also assisted us on another project to successfully arrest settlement of an engineered earth mattress below a 3 000 m³ 9 m high bulk water bladder tank.
“Regarding our recent foundry reclamation pit project, stabilisation of the 4,5 m deep excavation in poor soils in a confined space within a working factory would typically require demolition for and pre-installation of a pile wall around the excavation perimeter. This would have necessitated local demolition of the floors, followed by pile installation to stabilise the proposed excavation perimeter and protect the surrounding foundry space – a messy, time consuming, expensive and space disruptive operation.
“Geo-polymer resin injection through small drill holes in the floor from an injection pump located remotely was a significantly quicker, quieter, more cost effective and cleaner
Drilling in preparation for resin injection at the base of one of the affected columns
solution that enabled the civils contractor to mobilise earlier and excavate vertically to the external pit dimensions.
“The excavation stood open for several weeks during construction. There was no significant sidewall collapse or instability encountered, notwithstanding vibratory foundry operations nearby and a perched water table that was encountered at about 3,5 m below floor level. We would certainly consider the Uretek solution again for future projects.”
How common are subsidence issues?
For existing structures – whether they be homes, factories or offices – a knock-on effect of climate change is a major increase in rainfall, and flooding. Where stormwater systems cater for this, the impact is reduced. However, in many cases, drainage systems are inadequate and have a negative impact on structural foundations in terms of water intrusion.
“Sometimes subsidence problems can be caused by basic plumbing faults. For example, building downpipe installations that don’t connect to a formal drainage conduit. Here the erosive force of ongoing water impact on surrounding found material causes settlement. This is a common problem which we’re often called in to remediate,” says Pappalardo.
Realignment and non-piling solutions
Another area of specialisation is in remedying complex realignment issues that aren’t due to settlement issues. A prime example is the solution provided for a contractor during a series of warehouse developments. In certain instances, it was discovered that the precast columns installed (varying in height from 12 to 14 m) to support the roof trusses were off-vertical within their cast in-situ concrete 2,5 x 3,5 m bases.
“As on most projects, the contractor was under major time pressure. One option would have been to demolish and recast the concrete bases, but the solution we provided was far more practical from a time and cost perspective,” Pappalardo continues.
For each affected column, Uretek’s team injected geo-polymer into the base on the leaning side. This created a lever effect that pushed them into their correct vertical alignment, as verified by an engineering surveyor. What seemed like a nightmare scenario for the contractor was simply remedied.
In other cases, Uretek has provided an upfront intervention to accommodate construction upgrades. An example is a building renovation
CLOVELLY RETAINING WALL PROJECT
Uretek Geo Systems provided a non-piled foundation stabilisation solution for an extensive retaining wall forming part of a road widening project in Clovelly, Cape Town
in Johannesburg’s CBD where two additional floors were added within an existing triple volume space. To meet the increased load, the client’s engineer approached Uretek for a solution, which entailed soil strengthening below the foundation.
Uretek has also provided solutions where piling could not be employed due to space constraints. A past example is the construction of an extensive retaining wall forming part of a road widening project in Clovelly, Cape Town. This narrow coastal road runs parallel with a rail line terminating in Simon’s Town.
Since the retaining wall was to be founded on beach sand (the reason why piling would
have been the first choice), a comprehensive ground support methodology was required. Based on the agreed engineering design, the contractor first cast the concrete founding slab. Thereafter, Uretek injected a slow reaction resin underneath to maximise the expansion reach and optimise the overall bearing capacity. The strengthened sand was as solid as concrete.
“The endless flexibility of the UDI process is well proven locally and internationally, and with ongoing research and development into advanced geo-polymer formulations there are very few foundation structures that cannot be restored to their full integrity,” Pappalardo concludes.
DETERMINING THE LIKELY TRACKING CHOICES OF UTILITY-SCALE PV POWER PLANTS
outperform fixed-tilt systems in terms of energy production. In my research, I found energy gains of 12.9% to 20.1% could be achieved annually by using single-axis tracking systems as opposed to fixed-tilt systems. By analysing the Levelised Cost of Energy (LCOE) – a measure of the average net present cost of electricity generation for a plant over its lifetime – my research aimed to determine which configuration would offer the lowest LCOE. Across all scenarios and locations, singleaxis trackers consistently emerged as the most cost-effective solution. Despite the higher upfront costs, the energy gains from using trackers more than offset these expenses. This resulted in a lower LCOE compared to fixed-tilt systems.
South Africa is at a critical juncture in its energy transition. With Eskom predicting that solar PV's contribution to generation capacity will grow to 19% by 2030, it is clear that solar energy will play a pivotal role in our future power generation. Understanding the power production profile for PV plants is critical in ensuring the right decisions are made on the generation technology mix to best meet the country’s electricity demand. A critical decision when it comes to utilityscale PV plant centres on how the modules are set up on the site and whether the modules are fixed in place and angled to compensate for the latitude (fixedtilt) or track the sun during the day on a single horizonal axis (single-axis tracking). The
Shaniel Lakhoo
Solar photovoltaic (PV) systems have a significant role to play in increasing the power generation capacity in South Africa. However, the PV power generation profile used in South Africa’s recent long-term planning simulations does not accurately represent the current and expected future PV power generation in the country. By
choice has significant implications for costeffectiveness, energy output, and ultimately, influences when and how much power may be injected into the grid.
The importance of accurate PV power generation profiles
The accuracy of PV power generation profiles is crucial for long-term power generation capacity expansion planning. These profiles inform the broader energy mix and capacity planning for the future. The country’s studies, included in the Integrated Resource Plan (IRP) 2019, show the predominant use of fixed-tilt systems with the IRP 2023 not providing sufficient information to conclude the profile used. This is despite the growing use of single-axis trackers in real-world projects.
Single-axis trackers, which follow the sun’s path throughout the day, generally
Part of my research included a sensitivity analysis to understand the most significant factors impacting LCOE. The analysis revealed that the Balance of System (BOS) costs and the Ground Coverage Ratio (GCR) are the most critical variables. Interestingly, the cost of land had only a minor influence on LCOE. This was true even with the upper band equivalent to more than four times the profits that could be expected from using the land for agricultural purposes.
Bifacial modules were explored in my analysis as these become more prevalent in the market and are being deployed in new projects. However, my simulations found that the additional energy produced by bifacial modules does not justify the 6% premium over single axis trackers. For fixed tilt systems, the added energy was sufficient to make this the lower LCOE solution.
These insights are crucial for decisionmakers. The analysis showed that even in scenarios with lower GHI (Global Horizontal Irradiance), single-axis trackers with monofacial modules remained the most costeffective choice. Additionally, the plant design can be optimised based on GCR, knowing the cost of land is not a significant factor, thereby improving the overall feasibility of solar projects.
Creating a representative power profile
One of the valuable outcomes of my research was the development of a representative PV power generation profile for South Africa. This
Shaniel Lakhoo, Senior Electronic Engineer for WSP in Africa
was achieved by weighting the contributions from the eleven Renewable Energy Development Zones (REDZ) across the country, against the expected deployment of PV according to the Integrated Resource Plan (IRP) 2019. The resultant profile blends these contributions to create a profile reflecting the anticipated future solar generation.
This new profile is based on the most costeffective solution identified in my simulations (single-axis trackers with mono-facial modules) and provides a revised profile that forms a more reliable basis for future energy planning. It is a step towards ensuring that our long-term energy forecasts are grounded in the realities of the technologies we’re deploying.
The journey of exploring PV tracking choices has underscored the importance of aligning our energy planning with the latest technological and market advancements. As South Africa moves towards decarbonisation, it is crucial that our long-term planning reflects realistic predictions, rather than solely historical data or outdated assumptions.
The transition to renewable energy is not just about adopting innovative technologies. It comes down to making informed decisions that will shape the sustainability of our energy systems for decades to come. In the case of utility-scale PV power plants, that means ensuring representative profiles are used when completing long-term planning simulations.
Note: The insights shared here follow the conference proceeding, based on Shaniel Lakhoo’s masters degree project. Lakhoo presented at the 2024 EEEIC International Conference on Environment and Electrical Engineering that took place in Rome.
Empowering South Africa’s IPPs for a renewable future
Since the inception of the Renewable Energy Independent Power Producer Procurement Programme (REIPPPP) in 2011, competition between Independent Power Producers (IPPs) have caused prices on each renewable energy bid window to come down significantly. In time, this should lead to lower energy costs for consumers. By Francois van Themaat
However, the greatest obstacle to unlocking South Africa’s potential to become a leader in the renewable field is available grid capacity and grid access. There are two parts to this. The first is the fact that South Africa’s aging grid requires significant upgrades and expansion.
These upgrades will take time and significant investment. There is, however, a vast amount of private capital and technical expertise ready to move into this sector. Eskom, with government’s support, need to welcome this and remove regulatory barriers in order to speed up grid upgrades.
The second part is regulatory certainty and the efficiency of processes to obtain grid access where this is technically available. This process is lengthy, costly and poses significant risks for developers.
Eskom has to advise where grid capacity exists based on rigorous scientific analysis and they need to establish clear processes for obtaining grid access while adhering to deadlines in order to remove the uncertainty for developers.
Flexibility within an evolving regulatory landscape
In the meantime, IPP developers will need to become more innovative in how to structure and develop large scale projects as both the regulatory landscape and the energy needs facing developers will be very different a decade from now. There will be fewer opportunities for developers to enter into 20-year offtake agreements with single clients.
We believe that a flexible approach is required in order to future proof projects as far as possible. Some examples that we are working on are shorter term wheeling deals with multiple off-takers,
structures where the off-taker and/or landlord also has a stake in the generation project and ensuring that plants are permitted to allow for the later addition of a battery component.
Significance of BESS
Battery Energy Storage Systems (BESS) will play a key role to enable a larger portion of South Africa’s energy needs to be met by renewable energy and to help stabilise the country’s energy supply. There are many roles BESS will play. Batteries can be used to shift daytime energy generated by solar plants into the evening hours. This means that one could increase the size of a solar plant with a specific grid connection (let’s assume 50 MW) by almost threefold without having to obtain a larger grid connection from Eskom as the excess daytime energy can be stored in the batteries and fed into the grid at the 50 MW capacity.
Smaller battery systems could also be used to target peak consumption periods, thereby avoiding the need for the grid operator to run Heavy Fuel Oil (HFO) or diesel generators during these times.
Conclusion
South Africa is currently at a point where it has the opportunity to reshape its energy industry and take the lead in energy initiatives by working together with both public and private entities to tackle regulatory and infrastructure obstacles effectively. By encouraging project models and making investments in grid enhancements, along with incorporating BESS solutions into the mix, South Africa can establish a sustainable energy landscape for the future.
Francois van Themaat, Managing Director of Large Projects at Sustainable Power Solutions (SPS)
The existing Nemato UF plant commissioned in November 2024 incorporates renewable energy elements
ADVANCING SUSTAINABLE MUNICIPAL
INFRASTRUCTURE
SOLAR PV UPGRADE PLANNED FOR PORT ALFRED’S NEMATO UF PLANT
EMI Koussi Investments’ commitment to sustainable infrastructure development is firmly aligned with the future of municipal service delivery. A prime example is a solar photovoltaic (PV) and battery energy storage upgrade project scheduled for implementation at the Nemato ultrafiltration (UF) plant in Port Alfred, located within Ndlambe Local Municipality.
This upgrade represents a significant opportunity to transition towards a more resilient, cost-effective, and environmentally sustainable model for municipal water treatment facilities. It also provides Port Alfred – a vibrant tourism hub – with additional energy security in terms of delivering uninterrupted potable water supply to local businesses, communities and visitors during Eskom power outages.
“Furthermore, it will ensure a more predictable and financially sustainable operating model for the municipality, providing a buffer against Eskom tariff increases. It also improves the municipality’s eligibility for green finance and donor support on other future projects,” explains Dr Noluthando Vithi-Masiza, Director: Infrastructure Planning and Development at Ndlambe Local Municipality.
“For this upgrade project, funding is being provided by the Department of Human Settlements as part of their broader sustainability mandate in terms of bulk infrastructure provision. In addition to housing, the department’s focus is on maximising the living experience within communities, which includes water, sanitation, energy, roads and transport. This aligns with Ndlambe’s vision as a catalyst for socio-economic prosperity in our region.”
The 2,5 Mℓ/day Nemato UF preassembled and tested plant was commissioned by EMI Koussi Investments subsidiary Sizwe Amanzi Investments
(SAI) in November 2024 to meet the municipality’s need for increased capacity. It is paired with Ndlambe’s older conventional treatment works on the same site footprint. The latter employs standard flocculation tanks with gravity media filtration. The UF plant provides a critical backup in meeting spikes in seasonal demand. It also allows the municipality to shutdown parts of its conventional plant for maintenance.
A key feature of the UF plant is that it was configured from the onset as a green solution, incorporating a dedicated PV backup system
designed to support critical services such as lighting, instrumentation, PLC control systems, and site security. The current backup system includes a 5 kW inverter, eight 555 W high-power solar panels, and two 100 Ah lithium batteries, providing approximately 8 to 10 hours of night-time backup runtime.
“However, while effective for essential loads, this system does not support full UF plant operations – a gap that the PV upgrade will address,” explains NJ Bouwer, CEO of EMI Koussi Investments. A Level 2 BBBEE entity, the group’s operating divisions – which include Servelec, Sizwe Amanzi, and its strategic training partner, The Water Academy – work collectively to provide turnkey solutions in water and energy.
“Studies show that energy consumption typically accounts for up to 40% of operational costs at
The proposed solar PV array for the upgraded Nemato UF plant
water treatment facilities. Therefore, reducing this dependence on Eskom-supplied electricity and diesel-powered generators is a primary objective for Ndlambe, and the proposed solar PV installation is expected to deliver substantial cost savings throughout the plant's operational lifetime,” Bouwer continues.
This includes the upfront design capability to progressively increase the UF treatment capacity through modular additions to around 7 Mℓ/day, backed by an evolving PV footprint. Over time, the municipality’s strategy is to ensure that the conventional plant (currently grid dependent) and the UF plant can run as a complete off-grid solution.
“As for our water treatment works, our future vision is to have our allied wastewater works, and our RO desalination plant also operating as standalone PV-powered facilities as part of our resilience strategy, and to ensure that we consistently achieve full Blue and Green Drop status,” says Vithi-Masiza. “The ultimate goal for Ndlambe is to be energy independent.”
System design
The proposed UF plant renewables upgrade comprises a 159 kW solar PV array, consisting of 270 tier 1 PV panels rated at 590 W each. Energy conversion and management will be handled by ten 15 kW inverters, supported by a 150 kW gateway module to ensure efficient system integration and control. Energy storage will be provided by 50 batteries, each with a 10 kWh capacity, enabling reliable plant operation during periods of low irradiance or at night.
All inverters and batteries are to be housed in a purpose-built containerised unit on-site. The PV panels will be installed on a customengineered ground-mount structure, preserving full accessibility to the plant infrastructure without disrupting existing operations.
AI optimisation
A key innovation within the proposal is the deployment of AI-optimised energy storage technology. The selected battery system, SigenStor, incorporates a cloud-native architecture combined with machine learning capabilities, allowing the system to self-evolve over time. This ensures dynamic adaptation to operational demands (i.e. fluctuating load cycles), delivering tailored energy management that enhances cost savings and contributes to sustainable service delivery.
The Sigenergy system also carries a 10-year swap-out warranty, providing peace of mind through hassle-free replacement in the event of hardware failure. Designed with built-in redundancies, the system ensures a continuous, reliable power supply even if individual
* Note that no attributed capital costs is included for the Eskom connection point and the generator unit
* PV installation showing a positive return on investment within 5 years
* Year on year rising cost for electricity as supplied by Eskom and generator running costs
components are compromised – maximising uptime and operational resilience.
Scalability and real-time control
In addition to its advanced energy management capabilities, the system is designed for seamless scalability. This ensures that as energy demands grow or operational requirements shift, additional capacity can be integrated with minimal disruption, making it a future-proof solution.
Moreover, real-time system monitoring and diagnostics are integrated into the platform, offering facility managers live insights into performance, efficiency, and potential problems. This level of transparency not only boosts operational control but also facilitates proactive maintenance strategies, ultimately enhancing system longevity and lowering total cost of ownership.
Implementation
Execution of the installation will be undertaken by Servelec. With extensive experience in implementing solar PV and alternative energy systems for critical infrastructure across South Africa, Servelec brings proven expertise to the project. In turn, ROMH Consulting Engineers have been appointed as the consulting engineers for the project, supporting the design and implementation process. Together, Servelec and ROMH will ensure that the system is delivered to the stringent safety, reliability, and performance standards expected of municipal engineering projects.
“Once the upgrade has been completed, we believe that the project has the potential to set a new benchmark for future infrastructure planning and energy sustainability initiatives across the municipal sector,” adds Bouwer.
“EMI Koussi Investments remains committed to partnering with local municipalities to deliver practical, scalable solutions that meet the needs of today while securing the future. The solar PV upgrade at the Nemato UF plant is an important step in realising this vision – demonstrating how thoughtful engineering can align operational resilience with economic and environmental responsibility,” Bouwer concludes.
www.emikoussi.co.za
FIGURE 1: A comparative cost analysis for the Nemato UF plant solar PV upgrade over a 10-year period
New Market Street site rezoned for affordable housing
Cape Town’s stock of affordable housing units will be receiving another boost from Concor following the company being awarded a centrally located land parcel less than a kilometre from the central train station.
The New Market Street site in Woodstock – currently leased as a parking lot – is one of several land parcels rezoned by the City of Cape Town and made available for the development of much-needed affordable housing. According to Mark Schonrock, Property Development Executive at Concor, the project will deliver at least 375 affordable rental housing units for qualifying residents who earn less than R22,000 a month. There will also be more than 400 residential units made available on the open market.
The mixed-use project will comprise two nine storey blocks up to a height limit of 25 m. One of the buildings will be designated for affordable rental housing while the
second block – accessed from the same central podium – will be for open market sectional title owners. The project will include some small-scale retail opportunities.
Prime location
“Measuring just under a hectare in size, the site is remarkable for its prime location and scenic views,” says Schonrock. “Located right on the edge of the city centre, it is well serviced by multiple public transport systems – making it incredibly convenient to reach workplaces, retail areas and other key amenities for residents.”
The development is in Cape Town’s PT2 Zone, he says, indicating that it provides easy access to the MyCiTi bus transit line – which has a station on the project’s doorstep – as well as the train line, Golden Arrow buses and taxi routes. It is walking distance from the central station, and a similar distance from the Woodstock station.
Concor won the opportunity to develop the land parcel through its submissions to Request
for Proposals (RFP) on an open tender basis issued by the City of Cape Town. This required a conceptual design with extensive input from architects, urban designers and consulting engineers working in partnership with Concor.
Construction is expected to begin in the first quarter of 2026, kicking off a build timeline of about 22 months. To achieve this, Schonrock says Concor will continue its close collaboration with the relevant departments in local, provincial and national government as well as its professional partners in the private sector.
“As an established construction and development player in South Africa with a solid reputation in the sector, we are proud to partner again with the City of Cape Town in its forward-thinking land release programme to drive more affordable housing,” he says.
The City of Cape Town has over 6 500 social housing units at various stages of the planning pipeline, across 50 well-located parcels of land. It is also encouraging national government to make its unused land in the city available for this programme.
An artist’s impression of the residential apartments from New Market Street towards the city of Cape Town
A bird’s eye view of the development site at the Russel Street intersection with market residential units on the left and social housing apartments on the right
An artist’s impression towards Table Mountain
New lamella clarifier enhances Eswatini treatment plant throughput
Local water and wastewater EPC contractor, WEC Water, has successfully completed a contract for the design, manufacturing, installation and commissioning of a lamella clarifier for an existing water treatment plant in Eswatini. The contract forms part of an upgrade project, which aims to improve water access and quality to the surrounding communities.
The 12 m lamella clarifier – complete with an integrated flocculation zone – clarifies up to 2 MLD of raw river water prior to being fed to the plant’s existing sand filters for a further reduction in total suspended solids. The coagulant is dosed upfront to enhance the settling characteristics of the suspended particles. The clarifier is desludged daily, based on a timer, by opening the automated desludge valve for a suitable duration of time.
The lamella packing installed inside the clarifier increases the available surface area, resulting in a smaller required footprint compared to conventional clarifiers. The smaller footprint makes it easier to integrate into existing plants. Furthermore, the inclined plate design of the clarifier prevents sludge build up. Its simple operational requirements require minimal operator intervention, reducing costs and enhancing reliability.
The project took a total of 14 weeks to complete from design to plant handover, meeting the proviso from the client that the project was to be completed before the three-week contractors’ break over Christmas.
Says Ashly Forster, Project Manager at WEC Water, “A team of 20 worked tirelessly to meet the deadline. Factory acceptance testing and commissioning were completed a week ahead of our schedule, which is testimony of the collaboration of the execution team.”
Adds Forster, “WEC Water has worked with this client on several water and wastewater treatment projects across Eswatini. The strong partnership has fostered trust from the Kingdom’s water authority in our ability to deliver tailored, highquality solutions for every application.”
WEC Water has supplied a 2 MLD lamella clarifier, complete with associated equipment, for a water treatment plant upgrade project in Eswatini
SAPPMA warns against the use of recycled material in HDPE pressure pipes
The Southern African Plastic Pipe Manufacturers Association (SAPPMA) has issued an urgent warning to the plastic pipe industry, cautioning against the growing and dangerous trend of manufacturing HDPE (HighDensity Polyethylene) pressure pipes using recycled materials from external sources.
Jan Venter, CEO of SAPPMA, cautions that this practice, which violates both international and national standards (ISO/SANS 4427-2), is not only illegal but also poses a significant risk to public health and infrastructure reliability. Despite repeated warnings, the association reports that the use of sub-standard “80/20” pipes – made with 80% virgin material and 20% recycled material – is still prevalent in the local market.
“The use of recycled material from external sources in pressure pipe systems is strictly prohibited for a reason. It drastically compromises the performance and lifespan of the pipe, and when used for potable water, it could have serious health implications. Our industry cannot afford to cut corners for the sake of cost-saving. The long-term risks and financial consequences are simply too high,” Venter warns.
SAPPMA points out that the relevant HDPE pipe standards only allow for the inclusion of reprocessed material originating from a manufacturer’s own, in-house production scrap. Since no pipe manufacturer generates 20% internal waste, any pipe labelled as 80/20 will, by default, contain external recycled material – making it non-compliant with the national product standards and SAPPMA’s Code of Conduct.
The consequences of using these inferior products include:
• A drastically shortened operating life, resulting in unexpected and costly failures.
• Disruption of critical services due to premature pipe bursts or leaks.
• Health risks, especially when used to convey drinking water.
• Legal and reputational risks associated with transgressing standards.
“As pipes form part of long-term infrastructure investments, short-term cost savings should never come at the expense of safety and quality,” Venter adds. “We’ve seen real-world examples where this cost-cutting measure has backfired spectacularly, causing millions of rands in damages and service interruptions.”
To support the industry in making informed choices, SAPPMA continues to provide training, resources, and technical guidance. A recent webinar hosted by the association featured insights from a European expert who confirmed that the dangers associated with using recycled content in pressure pipes are universal and well-documented.
SAPPMA urges engineers, buyers, and municipalities to consult the “Guide to assist buyers of plastic piping systems” available on their website at www.sappma.co.za, and to reach out directly for any clarification on product compliance and standards.
WATER EFFICIENCY
BUILDING WATER FOOTPRINT MANAGEMENT FOR GREENER INFRASTRUCTURE
Water footprint awareness refers to our understanding and consciousness of the amount of freshwater used by individuals, communities, businesses, or products throughout their lifecycle. It involves recognising the impact of daily activities, consumption patterns, and production processes on water resources.
The concept of a water footprint considers not only direct water usage but also the indirect water usage embedded in the production and supply chain of goods and services.
Water footprint awareness and action is a critical component of broader environmental education and sustainability initiatives. By making individuals and organisations aware of their water footprints, it becomes possible to inspire positive changes in behaviour and encourage the adoption of water-conscious practices. This awareness contributes to a more informed and environmentally responsible approach to water management, helping to address global water challenges and promote a sustainable future.
Proactive steps
The following are some proactive ways to engage colleagues, and decision makers about
their water footprint and the impact of everyday choices on water usage for buildings, with concrete examples:
Professional settings
1
Employee Education Programmes
Encouragement: Implement water conservation training programmes for employees.
Example: Organise workshops to educate employees about water-efficient practices in the workplace. Empower them with knowledge on how to contribute to water conservation efforts.
2 Smart Landscaping
Encouragement: Promote water-conscious landscaping practices around the office.
Example: Opt for native plants and implement efficient irrigation systems and practices in the office landscaping. It not only enhances the workplace environment but also conserves water.
3 Regular Maintenance
Encouragement: Emphasise the importance of regular maintenance of water infrastructure to prevent water wastage.
Example: Incorporate regular checks for leaks and plumbing issues as part of the office maintenance routine. Quick turnaround times can prevent unnecessary water wastage.
4 Water-Efficient Fixtures
Encouragement: Install water-efficient fixtures in workplace restrooms and kitchens.
Example: Start by upgrading office facilities with
low-flow faucets, and water-efficient toilets and then move on to consider sensor-activated taps. These changes contribute to a more sustainable and water-conscious workplace.
5
Sustainable Purchasing Policies
Encouragement: Advocate for sustainable purchasing practices that consider water footprints.
Example: Consider the water footprint of products and materials when making purchasing decisions for both personal and professional settings. Choose eco-friendly options that align with water conservation goals.
To encourage water-conscious habits, Rand Water has adopted a mixed method of education, awareness-raising, and practical activities through the Water Wise brand. By putting these examples and efforts into practice, Rand Water believes people and organisations may contribute to the promotion of a more ethical and sustainable use of water in both personal and professional situations.
Water consumed from surface water (lakes and streams) and groundwater
Water consumed from rainwater insofar it doesn’t become runoff
GREY WATER FOOTPRINT
Water needed to dilute pollutants down to safe concentrations
RHODES UNIVERSITY’S PLAN FOR A SECURE WATER FUTURE
Aimed at reducing its dependence on municipal supply, Rhodes University’s world-renowned Institute for Water Research (IWR) has been investigating alternative water sources and infrastructure improvements. The ultimate objective is to create a sustainable and resilient water system in support of Rhodes University’s research and academic projects.
The scientific assessment of the project's feasibility has been completed, providing a foundation for the engineering and policy steps that are now underway. Specialist research conducted to date has focused on three potential supplemental water sources, namely rainwater harvesting, greywater reuse, and groundwater supplementation.
While rainwater collection from rooftops was evaluated, findings suggest it is not a viable standalone solution due to the unpredictable rainfall patterns experienced in Makhanda, Eastern Cape, where the university is situated.
However, treated greywater (from showers and basins) has been identified as a cost-effective solution for irrigation and ablution. For optimum greywater reuse, infrastructure upgrades, semicentralised treatment systems and dual plumbing have been identified as priorities.
Overall, groundwater supplementation has been determined as the most viable approach, sourced from the Witteberg Quartzite aquifer (which stores groundwater beneath the university and is replenished by rainwater). A groundwater model showed that existing boreholes could be part of the demand, with additional boreholes needed for a full campus solution. Water treatment is part of the plan to ensure safety and compliance with drinking water standards.
“The university sits on top of a very good water aquifer with potential for supporting the university
in the environment with little adverse impact on the surrounding community,” says Dr Jane Tanner, head of hydrology at the IWR.
Phased implementation plan
The University is taking a structured approach to implementing its water security plan. Phase I focuses on the upper campus, which already has an independent water distribution system owned by the university. This phase will incorporate groundwater extraction and treatment, addressing around one-third of the university’s water needs.
In turn, Phase II will tackle the rest of the campus and introduce greywater reuse where feasible.
This phase will be more complex as the lower campus is integrated into the municipal supply, requiring new infrastructure.
Next steps: licensing and
feasibility study
To proceed with groundwater use, the university has begun securing a Water Use Licence from the
Department of Water and Sanitation. This involves regulatory approval, stakeholder engagement, and environmental impact assessments. Simultaneously, a feasibility study is being prepared to finalise the technical details and costs of implementation. This will include:
• Identifying precise borehole locations through geophysical surveys.
• Upgrading the campus water distribution network.
• Designing new reservoirs for raw and treated groundwater storage.
• Developing a modular water treatment plant.
• Setting up a comprehensive monitoring system for water quality and usage.
A sustainable future
Rhodes University’s initiative aligns with the commitment to environmental sustainability outlined in its Institutional Development Plan. By integrating groundwater use with efficient infrastructure and water-saving measures, the university is taking proactive steps to ensure a reliable water supply for students, staff, and research facilities.
While challenges remain, the progress made so far marks an important step towards a watersecure future for Rhodes University.
It is important to note that Rhodes University has always positioned itself as not just the university in Makhanda but, importantly, the university for Makhanda. The university will not cease its ongoing efforts to work for the improvement of the greater Makana municipality and all its communities.
The conceptual model grid showing the three aquifers located beneath Makhanda
Rhodes University
Tillite
Shale/Sandstone Shale Quartzite
Rhodes University forms an integral part of the Makhanda community
Building Information Modelling (BIM):
Why client leadership is crucial for South Africa
Held in March 2025, BIMcommUNITYAfrica’s BIM CoDE•SA Workshop 6 served as a pivotal platform for deepening South Africa’s national conversation around BIM in the built environment and was aimed at asset owners and facility managers
Building Information Modelling (BIM) is no longer an emerging concept globally, having been developed and refined over the past two decades. In South Africa, it is gradually becoming embedded within engineering and infrastructure practices, with the adoption of ISO 19650 as SANS 19650 by the South African Bureau of Standards (SABS).
For consulting engineers, the benefits of BIM are well-documented: improved collaboration, better design management, and a greater likelihood of delivering integrated designs under tight deadlines. Firms that have proactively invested in training, capacitation, and technology are already seeing improvements in efficiency and quality – even when their project stakeholders have yet to fully adopt BIM practices. However, widespread transformation remains incomplete. Crucially, the pull from asset-owning organisations – the ultimate beneficiaries of improved asset information – has not yet materialised at scale.
The pivotal role of clients in BIM adoption International best practice, as defined in ISO 19650, highlights the central role of the employer (or appointing party) in initiating BIM processes by clearly specifying information requirements during procurement. Without these specifications embedded in tender documentation, consultants tend to revert to minimalist outputs, limited to what is contractually necessary. Given that BIM delivery entails additional cost and effort, few firms can justify voluntary investment beyond the brief, especially under tight fee structures.
In the United Kingdom, BIM mandates in the public sector were motivated by the need to stretch public funds further, driving down
By Richard Matchett, Pr Eng
infrastructure delivery costs (Cabinet Office UK, 2011). In South Africa, similar aspirations exist: one major metropolitan authority aims to “build five clinics for the price of four” by reducing inefficiencies and minimising waste through BIMdriven project delivery. Achieving such outcomes, however, requires deliberate procurement of information management processes – no different from the procurement of design, documentation, or supervision services.
How should South Africa procure BIM?
A consistent, transparent method for procuring BIM services is critical. Asset-owning organisations must decide whether they require a comprehensive, high-detail information model or a fit-for-purpose, cost-effective solution aligned with operational needs. Clarity lies in defining these requirements at the outset.
Exchange Information Requirements (EIRs) provide a structured approach to specifying:
• The level of detail required at each project stage
• The data structures necessary to support operations and maintenance
• Integration requirements between BIM deliverables and existing asset management systems.
However, defining information requirements cannot be treated as an isolated exercise tied only to project delivery. It must be integrated into
the broader objectives of the client organisation. Employers must consider their information requirements alongside their need for a physical capital project. This requires an increased awareness of the long-term value of structured information during the operational phase – an asset that often exceeds the immediate value of the construction project itself over the life of the asset.
To achieve this, the traditional separation between capital expenditure (CAPEX) and operational expenditure (OPEX) departments within client organisations must be bridged. The definition of information needs should be a shared responsibility. Early involvement of asset management professionals – those responsible
Richard Matchett, Digital Practice Lead at Zutari
for operating and maintaining the infrastructure – is essential. These stakeholders bring critical knowledge about the data structures, attributes, and operational interfaces that will be needed once the asset is handed over.
Including asset management expertise early in the project initiation phase ensures that operational phase requirements are considered when drafting tender documents. This, in turn, allows the employer to specify appropriate, outcome-focused information deliverables that support both construction delivery and long-term asset management goals. Without this alignment, there is a risk that models will be delivered that are technically compliant but practically unusable for operations, thereby undermining the full value proposition of BIM.
Current efforts by South Africa’s BIM community are focused on raising awareness among client bodies to ensure they not only understand why to procure BIM, but how to specify the right level and type of information – balancing the immediate needs of project delivery with the enduring needs of asset operations.
Beyond construction: BIM’s value in asset operations
The long-term value of BIM extends far beyond design and construction. Structured, reliable information embedded in asset models directly supports better infrastructure operation, maintenance, and lifecycle management. In a resource-constrained environment like South Africa, better-managed infrastructure is more important than merely building more infrastructure.
Sound asset management depends on the availability of quality information. BIM lays the foundation for data-driven decision-making, enabling predictive maintenance, budget planning, and lifecycle optimisation. Structured information allows asset managers to respond proactively, improving service delivery and reducing total cost of ownership.
BIM is not simply about better drawings or construction coordination. It is a critical enabler for the digital transformation of South Africa’s built environment – aligning infrastructure delivery with the imperatives of the Fourth Industrial Revolution. With welldefined BIM procurement strategies, South Africa can build not only more resilient assets but a smarter, and more efficient, national infrastructure base.
Introducing the BIMcommUNITYAfrica
By fostering collaboration, sharing knowledge, and promoting best practices, the community aims to empower users and drive innovation in the South African construction and infrastructure sectors. This vibrant network serves as a hub for resources, events, and discussions that enhance BIM adoption and implementation, with the goal of enabling the country to harness the full potential of digital transformation in the built environment.
Email angela@bimcommunity.africa for further information and visit www.bimcommunity.africa
AI FUNDING MODEL UNLOCKS SME POTENTIAL
Andrew Maren, founder and CEO of PSP
Traditional funding routes often create hurdles for small and medium enterprises (SMEs) – from stringent credit requirements to lengthy approval processes, and red tape.
To address this, ProfitShare Partners (PSP) has developed an innovative software solution, using real-time data analysis and predictive modelling to assess funding viability faster, providing a platform for sustainable SME development, from manufacturing and logistics to retail and construction services.
Unlike conventional lenders that rely heavily on historical credit records, PSP incorporates alternative data points to evaluate business potential. This more dynamic, tech-driven strategy enables quicker decision-making. It also opens funding opportunities to a broader range of entrepreneurs, particularly those who may not have extensive financial histories, but demonstrate strong growth potential.
Automated document analysis
PSP’s AI-driven software automates document analysis, using machine learning algorithms to verify and assess funding applications. According to Andrew Maren, founder and CEO of PSP their AI technology is also a game-changer in fraud prevention.
As he points out, financial fraud is a growing concern for SMEs, as a single fraudulent transaction can have devastating consequences for a small business. However, by leveraging advanced AI-powered anomaly detection, PSP’s system can identify and flag suspicious transactions in real-time.
“This proactive approach not only safeguards SMEs, but also strengthens trust in PSP’s funding model,” Maren explains.
“Data is more than just numbers. It has become the key to unlocking opportunities for businesses that have traditionally been underserved. By continuously evolving our approach, we are ensuring that more SMEs can access the capital they need to turn their dreams into reality,” Maren concludes.
POLYMERS IN CIVIL ENGINEERING: A PRIMER FOR THE PRACTICING ENGINEER
Civil engineers, the builders of our world, are entrusted with the crucial task of designing, constructing, and maintaining the infrastructure that forms the backbone of modern society – from buildings and bridges to highways, dams, and water systems. Their role is pivotal, and the materials they work with have evolved. By Ian Venter
From the use of natural substances like stone and timber to the inclusion of metals, concrete, and ceramics, the field of civil engineering has been significantly revolutionised by the advent of synthetic polymers, particularly since the conclusion of World War II. Today, polymers and polymer-based materials are not just integral, but increasingly so, to civil engineering projects. They offer unique properties and functionalities
that complement or surpass those of traditional materials. Therefore, understanding these materials, their properties, and how they behave is not just essential, but also keeps engineering practitioners aware of the industry trends.
Materials as the “Food of Design”
The selection of appropriate materials is fundamental to successful design. Just as a chef carefully selects ingredients, a civil engineer
must choose the best materials for the job, fully exploiting their potential and characteristics. The design process involves considering function, material, shape, and process. Therefore, understanding the available “menu” of engineering materials is a critical first step and a weighty responsibility.
While civil engineering has long relied on concrete, steel, masonry, and aggregates, polymers represent a distinct family with
A former technical manager at the Southern African Plastic Pipe Manufacturers Association (SAPPMA), Ian Venter launched Polymers and Piping (fittings) Systems South Africa (PPfSSA) in June 2024. The company specialises in consulting on how manufacturers and end users can consistently achieve high-quality thermoplastic products, and providing comprehensive solutions for piping systems. Ian holds a National Higher Diploma in Polymer Technology and has significantly contributed to advancing industry standards in his field. For further information, phone +27 82 770 8244 or e-mail: IanVenter@PPfSSA.com.
Plastic sheeting installed prior to a concrete pour
properties and processing routes that differ significantly from these traditional materials.
What are polymers?
At a fundamental level, polymers are materials of very high molecular weight. They typically comprise many atoms connected to form long chains, often called the polymer backbone. These chains are built up from repeating one or more types of smaller molecular units called monomers. The synthesis of these large macromolecules from smaller molecules is termed polymerisation, a process where monomer units are joined repeatedly.
The atoms forming the polymer backbone are commonly carbon, oxygen, nitrogen, or sulfur, configured uniquely for each polymer. Other attached atoms like hydrogen, carbon, oxygen, chlorine, fluorine, and/or bromine further differentiate polymers.
The structure of polymer molecules can vary significantly. They can exist as linear, branched, or complex network structures. When chains join to form a network, this is known as cross-linking. This process involves the chains becoming united by chemical connections. Cross-linked polymers are generally insoluble and infusible, though they may swell in solvents.
Polymers can be broadly classified into natural polymers derived from plants and animals (like wood, rubber, cotton, silk, proteins, cellulose, shellac, and bitumen) and synthetic polymers synthesised from small organic molecules, often derived from coal and petroleum products. Many useful plastics, rubbers, and fibres are synthetic polymers.
Thermomechanical behaviour
Another essential classification, particularly from a processing and application standpoint, is their thermomechanical behaviour:
• Thermoplastics: These polymers soften when heated and harden when cooled. This characteristic allows them to be repeatedly melted and reshaped, making processes like extrusion and injection moulding possible. Examples include polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polytetrafluoroethylene (PTFE), PA (nylons), and polyesters (PET).
• Thermosets: These polymers harden permanently after a chemical reaction (often involving cross-linking) and cannot be melted or reshaped by heating. They are often processed as a mixture of fluid monomers or oligomers that harden in situ. Examples include phenolics and epoxies. Cross-linking forms a rigid network structure.
• Elastomers: Also known as rubbers, these polymers exhibit large elastic deformation. They are often cross-linked, which provides elastic properties. Examples include natural rubber, isoprene, neoprene, butyl rubber, and silicones.
Polymers can also be copolymers, meaning they comprise more than one type of monomer unit. Different arrangements of these units result in types like alternating, random, block, and graft copolymers.
Furthermore, solid polymers can exist in amorphous or crystalline states. Amorphous polymers have a glass-like structure and are typically transparent, while crystalline or semicrystalline polymers have ordered regions and tend to appear opaque or translucent. The degree of crystallinity significantly influences mechanical properties like modulus and strength.
Polymer composites: Blending for enhanced performance
Imagine if you could combine the best features of different materials to create a super-material. That's exactly what polymer composites do. They blend polymers with reinforcing fibres to create materials that are lighter, stronger, and more versatile than their individual components.
These polymer-matrix composites (PMCs) consist of a polymer resin acting as the matrix reinforced by fibres. Standard reinforcing fibres include glass, carbon, and aramid fibres. Examples are GFRP (Glass Fibre Reinforced Polymer), CFRP (Carbon Fibre Reinforced Polymer), and Kevlar-FRP.
From a civil engineering perspective, PMCs properties are desirable. They can be lighter than aluminium and stronger than steel. Historically driven by aerospace, automotive,
Thermoplastic pipes perform a key role in bulk water and reticulation networks
and aircraft applications, their use in the construction industry is increasing as appreciation for their unique properties grows. The following are some of the key mechanical factors to consider:
• Strength and stiffness: Polymers possess tensile strength, yield strength, and stiffness (measured by the tensile or Young's modulus). However, compared to metals and ceramics, bulk polymers generally have much lower stiffness and strength. Polymers' stiffness and strength are influenced by molecular weight, degree of crystallinity, and processing (like drawing or annealing).
Polymer fibres, especially aramid (like Kevlar) and exceptional grades of PP, can be significantly stiffer and stronger than bulk polymers, with properties comparable to or superior to carbon and glass fibres. The properties of polymer composites fall between the matrix and the reinforcing fibres. Due to their high mechanical strength, polymers are increasingly used as structural materials, sometimes replacing metals.
• Ductility and elongation: Polymers can exhibit significant ductility, measured by percent elongation. Some polymers can stretch considerably before fracturing. The way ductility is cited for semicrystalline polymers differs from metals in that the specimen gauge length does not need to be specified.
• Fracture toughness: This property measures a material’s resistance to crack propagation. On a measure related to apparent fracture surface energy (G1C), ceramics typically have
Polymer panels, including block and large panels, are used for walls and can be curtain, partition, or load-bearing
walls
lower toughness values (10 ³ to 10 ¹ kJ/m²) than polymers (10 ¹ to 10 kJ/m²).
While polymers generally have less fracture toughness than ceramics on a different scale (K1C), the higher G1C values for polymers help explain why they are more widely used in engineering than ceramics, despite being often perceived as “brittle”. Toughening mechanisms, such as rubber-toughening, improve the toughness of polymer matrices, which are vital for materials like strong epoxy adhesives used in structural joints.
• Viscoelasticity: Unlike purely elastic solids or purely viscous liquids, polymers often exhibit behaviour that combines both elastic and viscous characteristics. This timedependent deformation under stress, known as viscoelasticity, means their response depends not only on the applied load but also on the rate and duration of the load. Understanding this behaviour is crucial for predicting long-term performance, such as creep (deformation under sustained load) and stress relaxation.
• Fatigue: Polymers, particularly when used in load-bearing applications, are subject to fatigue failure – a loss of strength or performance due to prolonged or repeated (oscillatory) stress, even at stress levels below the material's yield strength. Attention to fatigue in polymers has increased as they become more prevalent in structures.
• Creep: As mentioned under viscoelasticity, creep is the time-dependent deformation of a material under a constant load. This is a critical consideration for polymers used in structural applications, as it can lead to long-term deflections.
• Friction and wear: Polymers and their composites are important in contact and relative motion applications, acting as tribological materials. Research focuses on understanding friction and wear mechanisms when polymer surfaces interact with others.
• Poisson's Ratio: This property, relating transverse strain to axial strain, is also studied for polymers.
Thermal, chemical and rheological properties
During manufacturing, temperature significantly affects polymer properties, especially mechanical ones like stiffness.
Key thermal transitions include the glass transition temperature (Tg), below which amorphous polymers are rigid and brittle and above which they become rubbery, and the melting temperature (Tm) for crystalline polymers.
The flow behaviour of molten polymers (rheology) differs from that of low-molecularweight liquids. Polymer melts are nonNewtonian, exhibiting shear thinning (viscosity decreases with increasing shear rate) and viscoelasticity (elastic and viscous components). Understanding this behaviour is critical for designing and optimising polymer processing operations like extrusion and moulding.
Furthermore, a polymer's chemical resistance to various environments is crucial
in civil engineering applications like pipes, coatings, and materials exposed to soil or water. Polymers used as binders in civil engineering require good cohesion, adhesion, and moistening properties relative to mineral surfaces.
Polymers can also be designed to have specific electrical properties and be permeable to certain substances, a factor important in packaging and potentially in civil engineering barriers or membranes. Some polymers are being explored as “smart” or “intelligent” materials.
Application of polymers in civil engineering
Polymers and polymer-based materials find diverse and growing applications across the building and civil engineering spectrum.
A prime example is adhesives, essentially polymer-based glues – an ancient technology now significantly advanced by synthetic polymer chemistry. From a structural perspective, many polymers are used to create bonds that perform a mechanical function, with synthetic adhesives being the primary type used in civil engineering. Application examples include their use as bonding materials and in concrete repair, including polymer-based materials applied in films or sheets tested for crack resistance on concrete.
Polymers are also used in various building applications, such as coatings, thermoplastic pipes, waterproofing compounds, flooring, and facade materials. Polymer panels, including block and large panels, are also used for walls and can be curtain, partition, or load-bearing walls. Another popular trend
Polymers are widely used in bridge construction and maintenance for applications that include elastomeric bearings and expansion joint seals
is the prefabrication of construction components like floor slabs, stairs, roofs, and wall panels.
Another growth area within the bridge segment is the use of polymers for elastomeric bearings and expansion joint seals. Polymers are also a key element in geotextile product developments for applications that include environmental engineering (e.g., mechanically stabilised earth walls) and pavement construction, where they provide benefits such as reinforcement, filtration, and separation.
Another evolving trend is the use of PMCs as replacements for metallic components in construction, as is the use of polymer fibres in concrete structures ranging from dams to rigid pavements.
Sustainability
A further notable trend is the evolution of mechanical and chemical recycling technologies, which present an even stronger business case for polymers. In addition to diverting potentially toxic waste from landfills, the renewable advantages foster the circular economy.
As mentioned previously, thermoplastics are well suited for recycling due to their composition (they can be melted down and reformed), while thermosets are not. Regarding the latter, they need to be shredded first and can be used as a filler in new product development. At this stage, chemical recycling – breaking down the thermoset polymer chains into their original monomers – is still in the early stages.
To provide practical guidance, concepts like Lifecycle Assessment (LCA) have been introduced as tools to evaluate the environmental impact of recycled or renewable polymers. This aligns with the civil engineer's growing responsibility regarding when and where recycling and reuse are safe and sustainable.
Designing with polymers:
Considerations for the civil engineer
The design process for civil structures involves assessing alternatives based on feasibility, aesthetics, and cost. Material selection is a key part of this process.
Engineers must consider the unique properties and behaviours discussed when designing with polymers and identify the “design-limiting properties” – the most critical for a material's performance in a specific application. For example, plastic bicycles failed commercially because their stiffness was insufficient. This highlights that selecting a polymer based solely on one property (like density or cost) without considering critical performance requirements (like stiffness in a structural frame) can lead to failure.
Designing with polymers, especially in load-bearing applications or where long-term performance is critical, requires a thorough understanding of their mechanical properties, including viscoelasticity, creep, and fatigue behaviour. Polymer behaviour under different temperatures and environmental conditions must also be accounted for.
The distinct processing methods available for polymers (extrusion, moulding, etc.) also influence design, as the process affects the final microstructure and properties of the component. Designing for manufacture, including consideration of joining and fastening methods, is also essential.
When all the factors are understood and applied, the ultimate result is an economic and environmental advantage that will withstand the test of time.
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New e-book offers insights into optimising building materials for sustainability and performance
The building materials and construction industry is undergoing rapid changes to address demands for sustainability, resilience, and efficiency. Trends such as recycled materials, carbon-neutral construction, and resource optimisation are transforming how materials are designed and applied to meet environmental and performance challenges.
Anton Paar is pleased to announce the release of a comprehensive e-book, A Practical Guide for Great Building Materials . This resource provides detailed insights into the characterisation and improvement of key building materials, including cement, concrete, metals, composites, and architectural finishes.
The e-book explores advanced techniques for analysing cement, including particle size and shape analysis, X-ray powder diffraction, and microwave digestion, to
ensure precise material characterisation. It also covers methods for optimising concrete quality, such as skeletal density
determination and in-situ X-ray diffraction for aerated autoclaved concrete. For metals, the guide delves into corrosion inhibition, steel hardness evolution, and the Bayer process for bauxite refinement.
In addition to these materials, the e-book discusses rheological testing of glass, humidity-dependent adhesive properties in wood, and dynamic mechanical analysis for composite materials. It also addresses architectural coatings and finishes, providing insights into rheological characterisation, viscosity testing, and scratch resistance evaluations for enhanced durability and performance.
This e-book serves as a valuable resource for professionals in research, quality assurance, and engineering. By combining real-world examples with cutting-edge techniques, the guide empowers users to meet industry standards while contributing to sustainable construction practices.
Download your copy of A Practical Guide for Great Building Materials today and discover innovative approaches to improving building material performance: https://bit.ly/44OCYUS.
ABOUT ANTON PAAR
Founded in 1922 in Graz (Austria), Anton Paar is the world market leader in the measurement of density and concentration, the determination of dissolved carbon dioxide, and the fields of rheometry and viscometry. Anton Paar’s customers include most of the major beer and soft drink manufacturers worldwide, companies active in the food, chemicals, petroleum, and pharmaceutical industries, as well as leading academic groups.
For many decades, Anton Paar has combined precise mechanical production with the latest achievements in the fields of research and development. In recent years, Anton Paar GmbH has invested up to 20% of its annual turnover in research and development. The company offers analytical solutions that are produced within its nine producing sites (in Europe and the USA).
The Anton Paar Group operates in more than 110 countries and has 35 sales subsidiaries and
11 producing firms in Europe and the USA. More than 4 200 employees in a worldwide network spanning research and development, production, sales, and support are responsible for the quality, reliability, and service of products made by Anton Paar. Since 2003, the Charitable Santner Foundation has been the owner of Anton Paar. It is dedicated exclusively and directly to charitable purposes.
ABOUT ANTON PAAR SOUTHERN AFRICA
Anton Paar Southern Africa (Pty) Ltd, established in 2013, is a subsidiary of Anton Paar GmbH, comprising of three branches based in Johannesburg (headquarters), Western Cape and KwaZulu-Natal; along with dedicated staff based in Tanzania, Ethiopia and Cameroon. With a total staff complement of 69, Anton Paar Southern Africa provides sales, application and technical support as well as a certified service offering to South African users as well as to Sub-Saharan Africa users.
Innovative solutions reduced construction time on the Haarbachtal bridge project
NEW HAARBACHTAL BRIDGE SKIDDED INTO PLACE VIA ELEVATED JACKING TOWERS
Mammoet are specialists in Accelerated Bridge Construction (ABC), possessing the engineering knowledge and equipment to allow bridges to be built closer to installation sites and assembled in larger, and therefore fewer pieces – saving considerable time and cost.
Arecent example is the Haarbachtal bridge, which crosses the Haarbach valley on the A544 highway, near Aachen. It dates from the 1950s and is a key bridge in Germany, connecting Aachen to Cologne.
Over time, the original structure, built in 1956, suffered damage in several places, initially limiting traffic to one lane in each direction and eventually requiring the structure to be replaced. This required a full closure of the
bridge and innovative approaches to shorten the construction time and get traffic flowing again as quickly as possible.
Mammoet was asked by AMAND Bau NRW to help launch the new steel composite bridge, which comprised two structures measuring 160 m and weighing 1 340 t. The project posed significant engineering challenges. Height was a factor, and the bridge needed to be launched at a downward 2% angle. Its new abutments and pillars were also positioned at a 30 degree angle.
Considerable planning and engineering were required to achieve this complex bridge launch safely and to schedule. Its structures would need to be skidded over jacking towers built onto taller supports for greater height and stability.
Skidding over jacks
The old bridge was rapidly dismantled using controlled explosives in January 2024. The two new substructures were constructed on site and their installation began in December that year. Mammoet’s scope was to transport the new bridge structures from their build location and position them over, and then onto, their newly fabricated pillars and abutments. Mammoet Self-Propelled Modular Transporters (SPMTs) were used to lift and drive the structures to the launch position near the first abutment on the east side of the bridge.
For this step, 68 axle lines of SPMTs were used, configured in four groups of trailers set up in six hydraulic groups. The front and back groups were put to a constant pressure, while the four in the middle prevented the bridge from deflecting excessively.
Before this, Mammoet assembled a complex jacking system to gradually lower each structure onto its foundations. It involved two different systems working in tandem, elevated on supports.
The jacking system could not be used on the pillars as the bridge structures needed to be set down on them. Therefore, temporary towers were erected beside the two pillars and abutments. On these sat Mammoet’s Mega Jack 800 system (two bases per tower) coupled with “correction” jacks (500 t and 800 t) fitted with launching plates equipped with Teflon pads.
“The height of the Mega Jack system was around 25 m, which is quite high and would not be self-stable with the acting launching forces at the top,” explains Koen Harthoorn, Lead Engineer at Mammoet. “Therefore, the
Launching of the second substructure
temporary towers were connected horizontally to the pillars and the abutments to achieve greater stability.”
“The Mega Jack system was finally stabilised with strand jacks and fixed bracings connected to the abutments. Because everything needed to be arranged at a 30-degree angle, it meant the forces would act in directions you wouldn’t normally expect. Taking that into account was an additional challenge.”
Launching at angles
The bridge structures were fitted with a “Vorbauschnabel” – a temporary nose section to help them land comfortably onto the next launching plate. This increased their length to 190 m and weight to 1 413 t.
During the launch, each SPMT group was gradually removed as it reached the edge of the first abutment. This continued until the remaining SPMTs no longer had any traction and the process was taken over by hydraulic stand jacks. Because of the two-degree slope, winches were used to act as breaks if needed.
The bridge was lowered with the Mega Jack 800 system on all four towers. At a particular stage, it was lowered on three towers, while on the fourth tower only a correction jack was used. The correction jacks also helped to level the bridge. Combining these two methods at the same time was a unique approach.
With the jacking towers taking three weeks to construct, the team suggested installing skid tracks between the east and west pillars and abutments. This meant the towers could be moved to the adjacent sets with minimal effort and reused when installing the second bridge structure.
Thanks to careful planning and innovative timesaving methods, construction was achieved in just 22 months, with each substructure taking one and a half days to install. This was accomplished during adverse weather conditions and on a busy site with groundwork taking place.
Enabling the bridge to be fabricated on-site was also an advantage. It could be constructed at normal working height, allowing the project to be carried out safely and more efficiently.
A substructure is launched at a height of 25 m
Temporary towers with the Mammoet Mega Jack 800 system
Built for high-output performance, the Astec GT205S mobile screen is purpose-engineered to process large volumes of abrasive, hard rock and sand with maximum efficiency and durability
ASTEC EQUIPMENT REDUCES QUARRIES’ COSTS AND INCREASES PRODUCTIVITY
Once regarded as low-tech, the quarrying industry today is embracing new technologies and pioneering methods to drive efficiency, safety and sustainability.
Quarries are demanding more features, benefits and flexibility than ever from their equipment, and just tough is no longer enough, according to Philip Saunders, product sales manager for Astec Industries’ Materials and Infrastructure Solutions divisions. He says that equipment such as the Astec GT205S mobile screen, GT125 mobile jaw crusher, and FT200DF track-mounted cone crusher are purpose-designed to meet these requirements.
The Astec GT205S is a powerful, adaptable screening solution designed for high-output applications, Saunders explains. “This three-deck mobile incline screen plant offers a combination of capacity, durability and customisation options,
An
making it a valuable asset in the aggregate processing and construction industries. It is fitted with a 5 x 20 screen and a Caterpillar C4.4 129 HP Tier III diesel engine.”
High production capacity
Saunders notes that the Astec GT205S’s key benefits are its high production capacity, customisation and support, and minimal downtime. “The GT205S is designed to process large volumes of abrasive, hard rock and sand efficiently. With the ability to handle up to 600 tph (or up to 726 metric tonnes per hour, with modifications), it is ideal for operations aiming to maximise material output.
“The Astec mobile screens team works closely with our customers, to modify equipment to meet specific production needs. Whether increasing throughput or adjusting design features, the GT205S can be tailored for optimal performance.
“With a robust design and reliable support, the GT205S experiences minimal downtime. It is estimated at under 10%, which is for standard maintenance. Quick access to parts and responsive service ensure maximum operational efficiency.”
This screening plant offers ideal hydraulic angle adjustment. This feature improves screening efficiency, especially for wet or sticky materials. It efficiently screens materials up to 102 mm in size, meeting stringent specifications for road construction and other applications. The GT205S’s large screen box enables the production of high volumes of material when producing straightforward products such as G7. But, with the three-deck four-product conveyor setup, there is an element of finesse available when coupled with the adjustable screen box,
Leading global equipment manufacturer Astec Industries is shaping the future of quarrying with equipment that combines strength and durability with the latest technology and innovation.
Saunders reveals. “This functionality allows the quarry to maximise high quality low yield products such as 5 mm and 9.5 mm surfacing stone.”
The Astec GT205S is renowned for its durability in harsh conditions. Built to withstand abrasive materials, it features strong hydraulic systems and durable components, reducing maintenance needs and extending machine life.
Mobile jaw is equally effective for aggregate and recycling applications
Also gaining ground globally is the Astec GT125 mobile jaw crusher, highly regarded in both virgin aggregate production and recycled material applications, particularly in the USA and Australia.
“Thanks to its large, dynamically balanced, heavy-duty flywheels, the GT125 generates up to 33% more inertia than comparable models,” notes Saunders. “This results in improved crushing efficiency and a lower cost per tonne over the unit’s lifespan.”
The GT125 features a 32 mm stroke that enables aggressive material processing, boosting throughput and reducing operational costs. It is built on a compact, sculpted frame optimised for maximum strength and durability while minimising weight and size. This engineering approach simplifies transport and setup – an advantage for contractors working across multiple sites. A manually folding conveyor head further reduces transport dimensions and shipping costs.
Reduce operational expenses by up to 50 percent
Quarries choosing the Astec FT200DF track cone crusher can reduce their operational expenses by
ideal combination of geometry, stroke and speed ensures that the Astec FT200DF track cone crusher delivers an aggressive crushing action and increased crusher capacity
up to 50 percent, Saunders states. He explains that this is made possible by the machine’s unique roller bearing design, which generates higher efficiencies.
The unit also boasts a patented tramp iron relief system that protects the crusher from costly failures, he notes. “This is achieved by minimising the impact of crusher overload shock transmitted to the components. This machine offers users an ideal combination of geometry, stroke and speed which delivers an aggressive crushing action and increased capacity. This exceptional unit is permanently precision balanced with protected internal counterweights.”
The FT200DF’s other notable features include a variable-speed hydraulic drive; remote closed side setting (CSS) adjustment; interchangeable
The Astec GT125 mobile jaw crusher is engineered for efficiency, with large, dynamically balanced heavy-duty flywheels delivering up to 33% more inertia than competing models, leading to greater crushing force, smoother operation, and a lower cost per tonne over the machine’s lifetime
sensor and it has a 95 ℓ lube oil tank with an immersion heater.
Saunders foresees growing demand for exceptional equipment that can optimise quarrying operations – like this powerful trio from Astec Industries. “With increasing infrastructure
Industries will play a crucial role in meeting this demand efficiently.
“A further benefit for Astec Industries customers is the reliable support and parts availability that they can be assured of. Strong OEM and factory support are essential for maintaining uptime. The
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• interact
• free exhibition stands
• complimentary delegate registrations
• brand representation at the event, promotion of your company in the conference proceedings magazine and online
• free entry for guests at the social evening and much more.
AfriSam has enhanced its Rheebok Quarry operation with the installation of a high-capacity Sandvik CH430 cone crusher from Sandvik Rock Processing. The upgrade ensures reliable, safe production with reduced maintenance and a lower carbon footprint.
Located near Malmesbury in the Western Cape, the granite quarry produces a range of materials, including aggregate stone, crusher sand, roadstone and ballast. According to Desmond Jacobs, AfriSam’s Senior Engineer for the Western Cape, this investment aligns with the company’s long-term capital strategy.
The decision to install the Sandvik CH430 was driven by key features such as its hydraulic Hydroset™ system and Automatic Setting Regulation (ASRi) system, both of which enhance performance and streamline maintenance. The Hydroset™ system enables precise automated closed-side setting adjustments, while the ASRi system continuously monitors and optimises crusher performance.
AfriSam upgrades Rheebok quarry with Sandvik crusher
“We appreciate how the Sandvik CH430 minimises operator intervention, allowing real-time adjustments to the closed-side setting,” says Jacobs. “This improves product size consistency and quality. The system also tracks key parameters like temperature and pressure, enabling proactive maintenance and reducing unexpected breakdowns.”
Oversize reduction
Jacobs notes that the new unit has already demonstrated its impact on product quality by reducing oversized material in the feed stream.
“Our initial assessments showed a dramatic reduction in oversize material being sent for secondary crushing,” he says. “This allows us to optimise throughput and potentially eliminate redundant processing steps in the future.”
A crucial factor in selecting the Sandvik CH430 was its compact footprint, which closely matched the previous crusher. “As a brownfields project, we had to work within existing site constraints,” Jacobs explains. “Matching the footprint was essential as we had limited time for installation and could not accommodate extensive structural modifications.”
PC Kruger, Business Line Manager for Crushing Solutions at Sandvik Rock
Processing, highlights the Sandvik Plant Designer platform, which helped optimise the model selection process. Additionally, the energy-efficient crusher, powered by a 132 kW motor, aligns well with AfriSam’s specification, contributing to lower energy costs and reduced carbon emissions.
With a local office and warehouse in Cape Town, Sandvik Rock Processing ensures AfriSam receives prompt technical support, spare parts and plant audits whenever required.
A Sandvik CH430 cone crusher has been installed at AfriSam’s Rheebok Quarry to improve efficiency, product consistency and energy consumption
The Sandvik CH430 cone crusher was selected for its compatibility with existing infrastructure and reduced installation time during Rheebok Quarry’s scheduled shutdown
Creative use of precast concrete anchors Cape motor museum
In what is undoubtedly a unique application of precast concrete in South Africa, 12 U-shaped precast concrete elements, manufactured by Concrete Manufacturers Association member, Cape Concrete, were used as the primary anchor material for the construction of a motor museum at Lourensford Wine Estate in Somerset West during 2022.
Limited by town planning to a maximum 900 m² footprint, architect Anton Heyn designed the building to resemble a barn and to accommodate as many cars as possible, 42 in all, as well as motorbikes and other memorabilia. A pair of timber barn doors at each gable end provides vehicle access and cars are displayed in four bays, each flanked by four of the precast structures.
5 The southern barn door car entrance mounted between two of the precast concrete elements supplied by Cape Concrete 1 2 3 4 5
1 One of Cape Concrete’s U-shaped structures with protruding rebar for connecting to in-situ roof beams
2 Shuttering for the in-situ roof slabs straddles the U-shaped precast concrete elements
3 One of the roof-truss assemblies which was mounted between two in-situ roof beams
4 The north-eastern precast concrete corner element (right) and Zincalume wall cladding and the visitors’ entrance (left)
One of the museum’s eight bays
PROJECT TEAM
Architect: Anton Heyn
Structural engineers:
GFC-Holdings (Gawie Combrinck)
Quantity surveyors: Piet Bentum
Main contractor:
Build A Way Construction
Precast concrete columns:
Cape Concrete
Fire engineer: Hannes Pretorius
Town planner: Gideon Roos
Lourensford:
Koos Jordaan, Tinus Potgieter
“To a large extent the exhibition space determined the shape of the precast concrete elements,” said Heyn. “In order to optimise our limited space allowance, we angled the two lateral faces of each column at 20° to create an additional 20% of exhibition space. This not only allowed 10 cars to be parked in two opposing fanned crescents in each display bay, but improved viewing angles as well.”
A 3 m wide central section, which runs the full length of the barn, forms the viewing area and another two cars can be displayed in the reception area situated in the middle of the building.
The precast structures were used to secure the building’s timber-framed walling and other construction elements. It was clad with aluminium roof sheeting, which was also used for the roofing above each of the four exhibition bay sections and the central reception area.
Roofing configuration
The roofing also comprised four 15 m x 2.6 m in-situ slabs, which were cast between the Zincalume roof sections and were supported at each end by the precast elements. The slabs were tapered from 350 mm to 250 mm to provide a slope for rainwater, which drains into
the hollow sections of the U-shaped precast units. Similarly, the five discrete mono-pitch Zincalume roofs slope in the same direction, draining into gutters mounted on the building’s western elevation.
In addition, eight 15 m x 2 m (height) in-situ beams were cast on either side of the four concrete roof slabs to support four wooden truss assemblies for the Zincalume roofing and its ceilings. The precast units are founded in 120 mm (depth) x 200 mm (width) U-shaped channels, which were cast into the footings.
“We had to increase the depth of the footings to ensure we didn’t compromise their structural integrity,” said structural engineer, Gawie Combrinck, managing director of GFC-Holdings.
“The original design had a 50 mm cover above the reinforcing steel, but it was not enough to accommodate the founding channel. So, we increased the cover to 150 mm to give us the required 120 mm channel depth. Once a precast unit was lowered into a groove it was shimmed level and sealed with a flowable nonshrink grout.”
“When I first arrived on site, I thought to myself this is beautiful concrete. I realised then that it heralded a spectacular concrete display, because with tolerances of less than 4 mm on
each, the precast elements were as perfect as you can get them. There was not a single crack on any of the precast units thanks to some heavy reinforcing,” Combrinck added.
Off-shutter finish
Cape Concrete director, Walter Botes, commented that because an off-shutter finish was required on all sides, the precast structures were cast vertically.
“This entailed pumping self-compacting concrete from the bottom of the mould, a process which eradicated air bubbles without the need for external vibration and gave a much smoother finish. The precast structures were cast with rebar extensions at the top to tie into the cast in-situ roof beams,” Botes explained.
“The four corner precast units were cast with an additional concrete wing to which the timber barn doors were attached. These units are all identical, except that of them two were cast with door openings for staff access. A single mould was used for casting all 12 units, but the mould required some slight modification for casting the four corner units,” he continued.
“Transporting the units to site required careful planning. Weighing 13 tonnes apiece, they were lowered onto their side and delivered
The paved area outside the museum’s main entrance
The
two at a time. Using lifting anchors cast into the top of the units, they were tilted into the upright position before installation. We used a four-legged chain running over two rollers, belt slings and a spreader beam to lower the columns into position.”
“This project is quite unique,” added Heyn, “and was completed in what was a fixed budget. Precast concrete is a very flexible and
malleable building product and I can’t think of any better material that we could have used, especially as we needed to opt for shapes which offered better space utilisation.”
“I’m very happy with the excellent finishes achieved by Cape Concrete. As an architect one couldn’t have expected better than this. It’s what we visualised, and it turned out perfectly.”
Lighting and landscaping
The motor museum follows the contours of the site and the flooring in each bay section is stepped down 200 mm. The floor has a very smooth finish which was protected during construction with plastic sheeting and a layer of sand.
As direct sunlight fades vehicle paint over time, the museum’s lighting is generated both artificially and naturally; diffused natural light is supplied by four corner windows in each display bay and by windows above the reception area. And an air pressure system has been installed to keep the museum as dust-free as possible.
The landscaped area surrounding the museum comprises an orderly combination
of exposed aggregate paving, cobble paving, gravel-covered paths, grass, potted plants and flower beds.
Concrete Manufacturers Association member, C.E.L. Paving Products, supplied 500 m² of its Brownstone course exposed aggregate paver, which was used to pave the vehicle entrance areas at either end of the building and a section flanking the museum’s main entrance. C.E.L. also supplied its bond paver, which was used as the paving’s header course.
Heyn said he specified C.E.L.’s Brownstone paver as one of the main landscaping elements because it is an attractive and durable non-slip product, which complements the site’s other landscaping elements.
“The paver is embedded with natural stone, which adds a natural look and feel to the museum’s landscaping ‘language’. We could have specified an in-situ paving installation but given that the site was built with several services which require maintenance or addons from time-to-time, paving blocks proved to be the more practical solution; they can easily be lifted and replaced without damaging or marring the paved surface,” Heyn concluded.
CONSTRUCTION
• Alkali-free set accelerators for shotcrete
• Products for mechanized tunneling: foaming agents for soil conditioning, polymers, sealants, lubrificants
• Products for grouting and consolidating
• Products for concrete repairing, protection and coating
• Products for waterproofing: synthetic waterproofing membranes, waterproofing accessories
A section of the completed building with paving extending into one of the U-shaped precast concrete elements
MORE THAN BRICK AND MORTAR
VEGA SUPPORTS A THRIVING CEMENT MANUFACTURING INDUSTRY IN SUB-SAHARAN AFRICA
Sub-Saharan Africa’s cement industry is thriving, with urbanisation and infrastructure development being key drivers. Since 2021, Nigeria had the largest cement-producing capacity, with Dangote Cement, operating from the Obajana plant in the Kogi state, producing more than 10.25 million tonnes annually.
Overall, the production capacity in Africa has increased from 262 million tonnes annually in 2014 to 386.1 million tonnes in 2024. The cement industry in Sub-Saharan Africa is built for success.
With increased production, more storage is necessary, and additional challenges arise. Cement storage and transport require precise monitoring to ensure efficiency and prevent costly disruptions.
Before further processing, cement is stored in tall silos and transported using pneumatic conveying. Accurate level measurement, point level detection, and pressure monitoring are necessary to maintain seamless operations. Discrepancies in level measurement or pressure monitoring can lead to inefficiencies, costly
The VEGABAR 82 pressure transmitter monitors the pressure in pipelines. With its high overload resistance, it helps maintain stable transport of cement, preventing blockages and reducing wear on equipment
interruptions, or even equipment failure. A reliable monitoring system guarantees seamless operations.
Scenarios and technological solutions
Consider a plant facing frequent silo overfilling, pipeline blockages, and inaccurate level readings due to dust. These issues slow production and increase maintenance. To prevent these types of problems, the plant installs VEGAPULS 6X, VEGAWAVE 62, and VEGABAR 82 sensors for precise material handling and efficient operation.
A VEGAPULS 6X radar sensor provides noncontact level measurement in cement silos. Unlike traditional measurement devices, it is unaffected by dust, buildup, or process conditions, delivering precise and continuous readings. By ensuring accurate inventory management, operators can optimise material flow and prevent storage-related inefficiencies.
For overfill prevention, the VEGAWAVE 62 vibrating level switch is installed. This sensor detects high levels of cement in the silo, preventing spills and improving safety. Its robust design withstands heavy dust exposure, ensuring reliable operation without the risk of false alarms caused by buildup.
In the pneumatic conveying system, the VEGABAR 82 pressure transmitter monitors the pressure in pipelines. With its high overload resistance, it helps maintain stable transport of cement, preventing blockages and reducing wear on equipment. Reliable pressure monitoring ensures that the system operates efficiently, reducing downtime and improving overall plant performance.
By implementing these measurement solutions, the cement plant achieves accurate monitoring, reduced maintenance, and uninterrupted operations. With a system designed to withstand harsh conditions, operators can focus on productivity rather than troubleshooting equipment issues.
Continuous improvement
VEGA’s solutions go beyond simple measurement; they establish a groundwork for continuous improvement, resilience, and growth. As cement producers seek to optimise production processes and safeguard their workers, VEGA’s technology and expertise continue to set the standard, paving the way for advancements that go beyond just bricks and mortar.
VEGAPULS 6X radar sensors provide non-
Automated brick making plant slashes remote location building costs
Material transport is a major construction cost – the further the distance, the greater the expense. Take the case of bricks and blocks. If the building site is close to the brick plant transport costs are bearable. But when the blocks are needed in remote or inaccessible locations, transport becomes the major cost component.
Asolution to this problem is at hand. Rather than delivering bricks and blocks at prodigious cost it is now possible to produce them on site with the Click Brick™ system, a fully automated and portable brick and block making plant.
Designed and manufactured in South Africa by Machinecorp Industrial, Click Brick™ plants are housed in 6 m shipping containers which are easily transported to site. Moreover, they produce specially designed interlocking bricks and blocks that don’t require mortar.
Instead, the blocks are cast with ridges and furrows, allowing them to slot into each other,
thereby accelerating construction times by a factor of two. The blocks are also cast with two vertical cavities which means less weight, easier handling and better thermal properties, and, if needed, the cavities can be filled with concrete for door and window frame support.
Production output and materials
Click Brick™ plants are available in two models, the M1 which produces an average of between 1 500 to 2 000 masonry units per eight-hour cycle, and the M2, which produces up to 4 000 masonry units over the same period.
Unlike other portable brick making plants which are labour intensive, a Click Brick™ plant only requires two to three operators. What’s more it only uses two materials, soil and cement in a ratio of 90% soil to 10% cement, to produce blocks with a compressive strength of 6-7 MPa. In most instances, suitable soil is sourced on site, which
translates to considerable delivery cost and carbon-footprint benefits.
Click Brick™ containers are fully equipped to begin production within two hours of delivery to site and, where necessary, operational training can be provided. Featuring double doors at either end, both M1 and M2 models house a generator, rotary sieve, mixer, conveyor and casting machine. They also come with shovels, brick cutter, diesel jerry can, cement container and a compressive strength tester. And there is enough room to accommodate a skidsteer loader for digging and feeding soil into the plant and for conveying cast blocks to the curing yard.
Joachim Kofahl, Machinecorp founder, managing director, and Click Brick™ inventor, says Click Brick™ blocks are ideal for affordable housing schemes and for rural areas where bricks are either unavailable or prohibitively expensive.
“With locally sourced soil often freely available, Click Brick™ facilitates cost-effective on-site brick production. It is also ideal for short-term leasing and is perfect for business start-ups,” advises Kofahl.
Kofahl adds that another major advantage of mortar-free walls such as Click Brick™ is that they have a flexibility which makes them considerably more earthquake resilient than conventional brick and mortar walls.
“The Click Brick™ system is being marketed into Africa by Machinecorp and into the rest of the world by our Columbian agent,” Kofahl concludes.
A small house under construction using Click Brick™ blocks
Freshly-cast Click Brick™ building blocks are conveyor-fed for easy retrieval and stacking
Palletised blocks are cured prior to laying
CHRYSO ENHANCES THE AESTHETIC IMPACT OF CONCRETE
With growing demand for buildings that are not only functional but also visually striking, Chryso is helping customers reshape the face of concrete. Driven by technological advancements and a strong appreciation for architectural innovation, the company offers a broad portfolio of solutions that ensure concrete is both durable and beautiful.
Chryso’s curing compound ensures even moisture retention, reducing cracks and discolouration for a smoother more visually consistent concrete finish
According to Michelle Fick, Business Unit Development Manager for Concrete Aesthetics at Chryso Southern Africa, customers now have access to a wide range of innovative products tailored to various applications.
“To achieve the desired aesthetic impact, it is essential to consider how the concrete is applied,” says Fick. “That is why we offer a comprehensive suite of solutions, including surface retarders, integral pigments, surface treatments, curing compounds and demoulding oils.”
These products can be used in combination to enhance even the most basic concrete features such as pillars or floors, ensuring that aesthetics are never overlooked, regardless of the project’s scale or complexity.
One of the most common requirements in aesthetic concrete applications is colour consistency. Chryso’s integral iron oxide pigments provide vibrant durable colour throughout the concrete mass – so even chips or abrasions won’t reveal an underlying colour difference.
Surface quality is another priority. Chryso’s plasticisers and superplasticisers improve the workability and flow of the concrete mix, reducing surface defects and ensuring a smooth high quality finish. To further strengthen and enhance surface performance, the company also offers densifiers and hardeners that provide improved abrasion resistance. Additionally, its release agents support a clean separation from formwork, enabling a high class finish with consistent colour and texture.
Texture plays a vital role in the visual appeal of concrete. Viscosity modifying admixtures like CHRYSO® Quad 20 improve cohesion, preventing issues such as segregation or honeycombing.
Efflorescence – the white powdery residue that can appear on concrete surfaces – is a common challenge that Chryso tackles with products like CHRYSO® Fuge B, an integral waterproofing admixture that blocks pores and reduces the risk of moisture ingress. The company also offers water-repellent surface treatments, such as dry-coat sealers, which prevent water from reacting with free lime – the cause of efflorescence.
Colour consistency is one of the most common requirements in concrete aesthetic applications
Chryso plasticisers and superplasticisers, along with their Class 1 release agents and quality sealants, reduce defects in concrete
Surface finishing is key to consistency, and CHRYSO® FiniSafe can be applied just before the final finishing operation to enhance surface uniformity.
Best practice
Fick stresses that the success of any aesthetic concrete application depends on best practice. “Consistent batch control, quality materials and correct curing techniques are essential,” she says. “We always recommend proper concrete trials before commencing a project, especially for large-scale applications, to confirm the best combination of admixtures and placement methods.”
Chryso takes a collaborative approach, working closely with customers from planning to execution to ensure outstanding aesthetic outcomes. “Our innovations are designed to make concrete beautiful,” concludes Fick. “But it is our handson support that helps customers unlock their full creative and architectural potential.”
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
Zimile Consulting Engineers info@zimile.co.za
Zutari charmaine.achour@zutari.com
Watertight stormwater system for Mbudzi Interchange Project
Rocla’s Spigot and Socket stormwater pipes form an integral component of the Mbudzi Interchange Project currently under construction south of Harare and were specified based on their reputation for quality and performance.
The Spigot and Socket system is specifically designed to handle high-pressure environments, while maintaining their structural integrity despite any demanding conditions,” explains Robert Hill, Sales Manager for Infrastructure Specialist Group of companies (ISG) which includes Rocla.
This was a key factor in the system’s specification for the project, says Chris Muzondo, Commercial Manager of Tefoma Construction. “We know that Rocla products undergo rigorous quality assurance testing in order to comply with industry standards, and this makes them a highly recommended source of supply. Both the Harare City Council and the project consultant approved Rocla’s Spigot and Socket option.”
Designed to alleviate severe traffic congestion, the Mbudzi Interchange Project entails the modification of the original Mbudzi Roundabout with the development of a flyover and includes the building of 15 bridges, with 13 directly on the interchange itself. The works are being carried out on behalf of Zimbabwe’s Ministry of Transport and Infrastructural Development.
“We supplied 29 x 1 200 mm and 29 x 1 350 mm of 100D Spigot and Socket stormwater piping that in total measured 141 m, which we believed was the ideal stormwater solution for such a large and complex piece of infrastructure development. The Spigot and Socket design ensures easy installation with a reliable watertight connection that minimises the risks of leaks, making them the perfect choice for such projects,” says Hill.
Watertight seal
To keep the system watertight, a rubber “O” type ring is located on the tip of the spigot end of the pipe. When the pipes are joined, the rubber ring is compressed and rolls away from the tip down the barrel. A seal is then formed between the socket (or female end) and the outside of the spigot (or male end).
Catering for both stormwater and sewer applications, Spigot and Socket pipes are supplied in lengths of 2,44 m or 1,22 m and in 50D, 75D and 100D strength classes. Customised special strength designs can also be accommodated.
In addition to the Mbudzi Interchange Project in Zimbabwe, Rocla Spigot and Socket stormwater solutions have recently been supplied for main sewer line repairs at Queen Nandi Drive, KwaZulu-Natal, as well as for projects in Cape Town and Mozambique
Chris Campbell, CEO of Consulting Engineers South Africa (CESA), has expressed reservations about the proposed creation of an Office of the Engineer-General within the public sector, warning that it may introduce unnecessary bureaucracy and additional costs without tackling the core issues behind South Africa’s infrastructure challenges.
Chris Campbell, CEO of Consulting Engineers South Africa (CESA)
CESA voices concerns over proposed Office of the Engineer-General
In response to reports that the Department of Public Works and Infrastructure (DPWI) plans to proceed with establishing the Office of the Engineer-General South Africa, Campbell questions the effectiveness of adding “yet another” oversight structure. While oversight bodies, to an extent, play an important role in promoting accountability and service delivery, their effectiveness depends heavily on factors such as independence, adequate resources and institutional capacity.
While South Africa has institutions such as the Human Rights Commission, the Public Protector and the Auditor-General, these bodies often face challenges in maintaining their independence and ensuring their recommendations are implemented effectively.
Campbell raises critical questions: “Is an Office of the Engineer-General going to be able to effect meaningful change in infrastructure delivery that ensures value for money? Will it have the capacity and authority to exercise oversight on the full span of public entities responsible for public infrastructure delivery and add value to resolving the many issues that limit their own abilities to fulfil their obligations in this respect? Will it simply do what other such oversight bodies already do?”
“Regrettably, there is little evidence of any of the current findings of such existing bodies, leading to any level of consequence management that would deter the levels of maladministration evident in many of these public entities,” he states.
External and internal factors
Campbell also points out that the real obstacles to infrastructure delivery are multifaceted. These are both internal to public entities and external to these entities. Some of the external issues relate to organised criminal activity, vandalism and corruption.
“This is not limited to the prevalence of what has commonly been referred to as ‘the construction mafia’. We need to look further at why water supply systems are vandalised and why hospitals and schools are destroyed by fires, creating demand for water tanker contracts and rebuilding existing facilities –when in reality there is genuine need for adding new facilities to meet the growing demand for such public facilities,” Campbell continues.
Emphasis on professionalisation
Campbell urges the government to prioritise the professionalisation of the public sector, enforce consequence management and address
the damaging legacy of cadre deployment.
“This is without having ensured that persons responsible for managing such service delivery and infrastructure have the requisite skills and competencies to do so and without interference by non-executive partisan actors that has left many technical departments technically underresourced and most often not managed or mismanaged.
“Years of such appointments have overlooked the need for competence in senior management. Now we have a ‘logjam’ – even if we stop hiring unqualified individuals, the system is still clogged with people in such positions who lack the skills and knowledge to lead. In technical departments, junior engineers reporting to senior managers who lack the requisite skills and competencies become demoralised and leave the public sector, when in reality we need to retain and develop such people.”
To move forward, Campbell calls for a more practical and collaborative approach: “Let’s work harder to foster the partnership with the private sector to strengthen public sector departments with people who possess the correct skills and competencies and who additionally display the requisite behavioural traits to fulfil the role as a committed ‘servant’ of the public,” Campbell concludes.
TERRAFORCE has been providing the construction industry with sustainable earth-retaining solutions for more than 40 years and the system is now available on five continents.
Terraforce blocks are very versatile. They offer a horizontal and optional vertical interlock, allowing for seamless variations of wall inclination between 35 to 90 degrees, while their convex and concave corners and curves of unrestricted radius permits complex designs to suit any site conditions.
The blocks are designed to allow you a choice between round face, (plant supportive) or flush face (smooth or split version) finishes.
All Terraforce products are plant supportive and permeable.
Challenges with noise and dust?
For us it’s no problem.
From large stones to the smallest grains: Bulk solids come in all types, shapes and sizes, but choosing the right measurement technology is surprisingly easy. With our level and pressure sensors, you can effortlessly keep an eye on all your important process values – and still have time to crack the really hard rocks.
