Precast • Issue 2 • 2022

CONCRETE MANUFACTURING & CONSTRUCTION ISSUE 2 2022

R49,00

PRECAST

IN THIS ISSUE: Formwork release agents Towards sustainability Precast business development

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A LOT OF INNOVATION. EVEN MORE DEDICATION. QUALITY CEMENT. WHAT GOES INTO IT MATTERS.

Our range of high quality cement is designed for specialised applications where early strength is required. The fine-particle mineral components mean our cement offers improved durability and a superior quality concrete. When you’re putting everything into delivering a quality product, you need quality cement that delivers every time.

Ask for AfriSam.

www.afrisam.com

Creating Concrete Possibilities

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WORK, WEAR SAFETY APPAREL Branding available

Contact Lamees Mahomed | lamees@isikhova.co.za Mobile 084 590 5123 | Landline 011 883 4627 | www.isikhova.co.za

| CONTENTS |

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Editor’s NOTE

Something to smile about: according to the latest FNB/BER Business Confidence Index, business conditions are officially on the rise for the precast industry. Coupled with several projects across public-sector infrastructure, there should soon be enough work for everyone.

The challenge in this market is in the profit margins. The cost of materials is punishing for all and market corrections do not happen overnight. When so much has been asked of everyone over the past three years, it is by no means easy to ask for still more. Right now might be the best time to do so.

This edition of Precast focuses on the tools available to concrete precast manufacturers to both assess and improve operations from a technical, mechanical, operational and material perspective. We really are at a time of pulling through the toughest part of the recovery phase and this is when we need each other most. Reach out to colleagues and even competitors. This is the best way to find a perspective that will work for you.

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| CONTENTS |

COVER STORY PPC Cement RSA – 130 years as SA’s leading cement company

PRECAST R49,00

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CONCRETE MANUFACTURING & CONSTRUCTION ISSUE 2 2022

INDUSTRY NEWS 6 ​SA enters the Covid-19 recovery phase 8 Precast protection for a state-of the-art Cape Town pumphouse 10​ Casting in-situ makes a welcome comeback 11​ Localised precast modular reservoir construction 13 ​ SAICE competition recognises civil engineering research excellence 14​ Greening-up local labs for homegrown sustainable concrete solutions 16 ​ Unlocking development, opportunity and growth with renewable energy 18 ​ Concrete skills critical to unlocking publicsector growth strategy

PRODUCTS 20 ​Beit Bridge border upgrade’s massive demand for cement 23 ​Jacking pylons at Msika Bridge 26 ​ Casting innovations in Rosebank project

IN THIS ISSUE: Formwork release agents Towards sustainability Precast business development

ON THE COVER As PPC Cement RSA celebrates 130 years as the country’s leading cement producer, MD Njombo Lekula sheds light on the company’s proud legacy of building partnerships throughout the fabric of the country we call home.

PRECAST is independently published

by Isikhova Media (Pty) Ltd 10th Floor, Metal Box, 25 Owl Street, Milpark, South Africa Tel: +27 (11) 883 4627

TECHNICAL

www.isikhova.co.za Pubishing director/Editor-in-chief: Jason Aarons

28 The right way to apply release agents 31 ​Getting the most out of precast hybrid construction methods

E-mail: jason@isikhova.co.za Editor: Nicholas McDiarmid Tel: 067 672 2503 E-mail: nicholas@isikhova.co.za Director: Brand strategy: Jenny Justus

FEATURES

E-mail: jenny@isikhova.co.za

32 Reinforcing concrete slabs revisited 36​ Sustainability through extending admixtures 37​ Corobrik's R800m Kwastina factory in full production 38​ Moving towards sustainability 41 ​T he nature and outlook of the SA paint and coatings industry

Operations director: Thuli Majola E-mail: thuli@isikhova.co.za Creative director: Joanne Brook E-mail: joanne@isikhova.co.za Managing director: Imraan Mahomed E-mail: imraan@isikhova.co.za Sales manager: Ruwayda Mahomed Tel: 072 383 3203

GLOBAL VIEW

E-mail: ruwayda@isikhova.co.za Copy editor: Anne Phillips

48 Life stories told in a concrete voice

Media sales: Tel: +27 (11) 883 4627 / 083 450 6052 / 072 383 3203

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The views and statements expressed in this publication are not necessarily those of the editor or the publishers and neither the publishers nor the editor accept responsibility for them. No person connected with the publication of this journal will be liable for any loss or damage sustained as a result of action following any statements or opinions expressed herein. The same applies to all advertising. Precast© 2022. All rights reserved. No part of this magazine may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage retrieval system, without prior written permission from the publishers.

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| COVER STORY |

Describe your professional background and how that coincides with PPC Cement today.

I’m a chemical engineer by profession and hold a Master’s degree in business administration from the University of Stellenbosch Business School. I began my career on the technical side of the PPC business 32 years ago, but soon discovered a love of – and affinity for – the operational side of things.

I’ve held a number of leadership roles within PPC across various divisions, including overseeing the international division as MD of PPC Zimbabwe from 2013. In 2017, I took over as MD of SA and Botswana.

What are the priority areas under your stewardship and what guides your decision-making and execution?

My current role is to oversee and provide strategic guidance and direct PPC’s cement and material operations in SA, as well as in Botswana (operations and commercial).

My main focus has been on optimising and enhancing operational output, while delivering business growth and profitability.

This includes capacity expansion and optimisation, exploiting strategic synergies and exploring various alternative fuel and energy projects in the region.

I’m a firm believer in always looking for a win-win solution in every interaction I have. If you or the other party feel as if there’s only one winner, then it wasn’t a good engagement. A win-win solution guarantees longevity. If an interaction or engagement doesn’t offer a win-win situation, it’s one-sided and bound to fail.

I believe in a transformative management style, so I wouldn’t say I’ve “stamped my authority” on anything.

PPC is celebrating its 130th anniversary this year. What is it like working for such an illustrious brand?

I’ve been in the business for 32 years (I just missed the other 98 years!). It’s been an honour and a really challenging, yet exciting journey. PPC has provided me with great opportunities in my career, the greatest one being the role as MD in our Zimbabwe operations in 2013. The position came at an opportune time, as the country was coming out of hyperinflation

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PPC CEMENT – THE STRENGTH TO BUILD, GENERATION TO GENERATION Njombo Lekula, MD of PPC Cement RSA, takes time out from his demanding position to reflect on the significance of 130 years as South Africa’s leading cement producer and the power of this legacy to take on today’s challenges

| COVER STORY |

and we had to turn the business around.

The operation increased its earnings before interest, taxes, depreciation and amortisation added back by 45,6%.

It’s a great honour to be part of an organisation that’s been through so many eras of our country: 130 years of existence in SA has been no easy feat.

What are the challenges currently facing PPC? We’ve seen the impact of imports on our business and our economy at large. The South African market is set up to produce around 19 million tons of cement annually and the total demand in the country is estimated at around 13 million tons. This is a challenge for us, as it’s resulted in us having to mothball some of our operations due to low demand and high imports. I believe that public and private collaboration are key to changing the trajectory of the construction and built environment.

What has been the recipe for sustainability?

At PPC, we always value our partnerships with our stakeholders in the context of investing not only in our people, but also in the future of our country. As a strategic partner in the construction industry, our mission is to improve lives by empowering people to experience a better quality of life through the provision of a competitive product portfolio, superior customer service and going beyond just selling a product. Being agile in our responses to changing circumstances and collaborating with stakeholders to create the necessar y enabling environment, internally and externally, have helped sustain our business.

industry, we have the challenge of skills development. As a responsible corporate citizen, we haven’t sat back, but have looked at ways of closing the skills gaps.

We’re running with bricklaying, plastering and construction management accredited training courses across the country to empower the youth with skills that they can use in the market. Our contribution to communities cuts across many facets, including education, primary healthcare and infrastructure. Through partnerships with the JP21 Foundation and the Temba Bavuma Foundation, we’ve done great work with schools in relation to cricket development.

What sets PPC apart from its competitors?

It’s about going beyond. We don’t just sell cement and building materials – we sell value. Delighting our customers, technical support and providing more than just quality products are at the heart of what we do. We’re a 100% home-grown South African company.

What does the future hold for PPC? As a sector, as industry elders and leaders, we have to ask ourselves questions about our role in the creation of a massive infrastructure programme and we have to look at transversal partnerships in order to answer them.

L i ke a l l cou nt r ies , S A i s s lowly recovering from the aftermath of the Covid-19 pandemic, which has ravaged many economies. The question for us as a sector is how we can help in the recovery process. As SA’s largest cement producer, we recognise our role as an enabler and technology partner and the

vital importance of public, private and community collaboration.

We also recognise the global threat of climate change and the immensity of the challenges associated with achieving netzero emissions by 2050. We’re committed to reducing our carbon footprint and participating in the collective actions needed to address key barriers to decarbonisation Furthermore, where possible, we’ll take a leadership role in the use of waste as a fuel source, as evident in our recent successful introduction of tyres at our De Hoek factory in the Western Cape and the use of biomass fuels in Rwanda.

When you step aside one day, what do you hope to be remembered for in your role?

Hopefully there’ll be many more Njombos that I’ll have helped elevate, who are wiser than I and can take this organisation to the next century.

W hat adv ice wou ld you g ive to people who dream of longevity at one company?

It isn’t about the number of years you spend in a business, but about the contribution you can make to it and the fulfilment of knowing that your purpose was served in the process. I’ve always said that the day I wake up without feeling passion and drive will be the day I leave. I’m fortunate that in PPC, I’ve always been challenged and given opportunities that have been meaningful and fulfilling.

How do you relax away from the office?

I enjoy playing golf, doing landscaping and home renovations. My wife Noxolo and I have two children, Ntsako and Gabriella.

What is your hope for PPC in terms of its legacy?

My hope is for PPC to see yet another 130 unshakeable years.

How does PPC give back to communities?

PPC’s purpose is to empower people to experience a better quality of life and this is evident in everything we do. We believe in giving back to communities in which we operate. One of the major challenges in SA at this time is unemployment and in our

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| INDUSTRY NEWS |

NEW COVID-19 DATA: SA HAS ARRIVED AT THE RECOVERY STAGE OF THE PANDEMIC A recently published South African study set out to determine sero-positivity against SARS-CoV-2 before the fourth wave of Covid-19, in which the omicron variant was dominant. Sero-positivity measures the presence of antibodies against the virus; it indicates past infection. The study focused on Gauteng, the country’s economic hub. Ozayr Patel asked Shabir Madhi to explain why the findings suggest that SA has reached a turning point in the pandemic This is an extract from the article which was first published by The Conversation Journal (www.theconversation.com) on 1 March 2022 and is republished here under the Creative Commons policy. Read the complete article here: https:// theconversation.com/new-covid-data-southafrica-has-arrived-at-the-recovery-stage-of-thepandemic-177933

By Shabir A Madhi, dean: Faculty of Health Sciences, Professor of Vaccinology and director of the SAMRC Vaccines and Infectious Diseases Analytics Research Unit, University of the Witwatersrand What we found The results show the levels of sero-positivity – in other words, what percentage of people have antibodies to the virus – among just over 7 000 people from whom samples were taken. From these results, the following rates were calculated:

• In those under 12 years of age, none of whom had received a Covid-19 vaccine, 56% showed the presence of antibodies to SARS-CoV-2.

• In those over 50 it was 80%, including 70% if unvaccinated and 93% if vaccinated.

• In high-density inner-city areas, the sero-positivity prevalence was 85%.

What the findings tell us The findings indicate that SA is moving into the convalescent phase of the Covid-19 pandemic – the recovery phase. This is likely to be the same in other countries with low or modest vaccine uptake, but high force of past infections. As such, SA needs to recalibrate its approach to the pandemic and start managing it as we would for other respiratory infections which also cause large numbers of hospitalisations and deaths.

So why do I believe that we are at the tail end of this pandemic? It depends on what metric you use. If it is about infections, we are not at the tail end. If it is about the number of deaths that will transpire from Covid-19 during 2022, relative to the number of deaths that will transpire from other preventable causes of death in countries such as SA, then I believe the country has pretty much approached the end of this pandemic.

In SA, about 10 000-11 000 people die of seasonal influenza every year. In 2019, tuberculosis killed 58 000 people. However, we are not declaring an emergency in SA to deal with flu or tuberculosis. Deaths from HIV, and complications from that virus, are about 70 000. Yet South Africa is not shutting down the country to prevent deaths and infections from these diseases either.

Now what?

Our f ind ings suppor t t he opt im ism expressed at the beginning of 2022 in SA that a turning point had been reached in the pandemic. Many in high-income countries dismissed this view as inapplicable to their settings, despite high vaccine coverage.

However, their experience has since generally aligned with that of SA. Lastly, better Covid-19 vaccines are required, but the world is no longer at “code red”. It is time to rebuild livelihoods, economies and all other facets of life that were affected over the past two years. This is particularly true in fragile low- and middleincome countries.

Disclosure statement Shabir A Madhi declares that his institution receives funding from the SA Medical Research Council, the National Research Foundation, the Bill and Melinda Gates Foundation, Novavax and Pfizer with regard to Covid-19.

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| INDUSTRY NEWS |

The City of Cape Town has embarked on a project to bolster the city’s water supply by accessing groundwater from the Table Mountain Group (TMG) Aquifer in the area surrounding the existing Steenbras Dam. Situated in the Steenbras Nature Reserve in the Hottentots Hollands Mountain range, the dam is one of several essential water reservoirs supplying the city.

The Steenbras wellfield is one of the city’s new water programme projects, involving the drilling of 12 production boreholes into a section of the TMG Aquifer on sloping land above the dam’s northern bank. The scheme will ultimately contribute a volume of up to 30 megalitres a day to the city’s water supply system.

Each borehole is being equipped with state-of-the-art electric pumps and control equipment, supplied by the main contractor, Hidro-Tech Systems. This equipment is securely contained in pumphouse structures constr ucted w it h reinforced precast concrete panels supplied by Cape Concrete.

Strong, environmentally safe and a great deal faster The pumphouse structures were originally designed as in-situ concrete structures, but this specif ication was altered by consulting engineers Zutari (formerly (Left): The joints between panels were sealed with a self-adhesive sealer which was used to create a tight waterproof seal.

PRECAST PROTECTION FOR STATE-OF-THE-ART

CAPE TOWN PUMPHOUSE “Each pumphouse structure measures 34m² and consists of four separate chambers, constructed on a concrete base. These were cast in-situ in a very controlled manner to minimise damage to the surrounding vegetation.”

(Left): The planned use of in-situ concrete was scrapped in favour of the ecological benefits of using precast concrete structures.

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| INDUSTRY NEWS |

Aurecon) in preference for precast panels.

The reason for the design change was the potential damage which spilt concrete and contaminated water could inflict on the environmentally sensitive ecosystem of the Steenbras Nature Reserve.

Each pumphouse structure measures 34m² and consists of four separate chambers, constructed on a concrete base. These were cast in-situ in a very controlled manner to minimise damage to the surrounding vegetation. Kiewiet Viljoen of HidroTech says that besides being potentially harmful to the environment, activities such as batching on site and in-situ wall construction would have taken much longer.

Putting it together “Substantial time-savings were gained by opting for precast concrete. Once the flooring was cast, it only took a day to a dayand-a-half to erect each of the pumphouse structures. What’s more, precast concrete panels offer exceptional strength – a very necessary feature in providing for vandaland theft-proof barriers,” says Viljoen Cast in Cape Concrete’s yard in 13 sizes, the panels came with external steel brackets to facilitate a Meccano-style assembly of the pumphouse structures. The joints between panels were sealed with Jointex, a self-adhesive sealer which was used to create a tight waterproof seal. The roofs were also constructed with precast panels which were tapered to facilitate water run-off. The roof panels were sealed

(Above): The panels came with external steel brackets that allowed for the Meccano-style assembly of the pumphouse structures.

(Above): The precast pumphouse structures were clad with natural stone for aesthetic appeal, rather than loose cladding.

(Left): The steel bracket design simplified the process, which took only a day-and-a-half to complete the precast assembly of each pumphouse.

with a polyurethane sealant and a flexible membrane supplied by Sika.

Viljoen explains it was necessary for the pumphouse structures to be waterproofed because they hold medium-voltage transformers, LV motor control centres and industrial PLCs. They also include vent ducting to avoid internal condensation.

Precast panels were also used to construct 7m² underground flow meter and valve chambers adjacent to the pumphouse structures. The chambers house electronic flow metering equipment and the pipework, which connects the boreholes to the main feeder pipeline.

Keeping it natural I n ke e pi n g w it h t he n at u r e - ba s e d environment, the precast panels were clad with natural stone for aesthetic appeal.

Loose cladding was not used on the roofs, as it would have probably been damaged by baboons and might have been harmed other forms of wildlife and personnel working at the site, so instead they were painted green.

Members of the project’s professional team included Baseline, civ il and construction work and Cape Concrete, precast concrete supplier and pumphouse construction.

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| INDUSTRY NEWS |

(Right): Prefabricated female and male muffs with M-threads, which are pressed onto the reinforcement bars.

While the world moves towards increasing innovation, there is a keen focus across industries on “new” products, processes and solutions to invest in. But innovation in the construction industry does not necessarily need to follow unfamiliar – and sometimes risky and costly – routes. Peikko SA is changing the local construction industry with a modern take on traditional construction methods.

“While it’s true that Peikko’s become known for innovative precast construction methods, this doesn’t mean we’ve stopped thinking critically about existing methods which are tried, tested and well-loved by the industry. Our goal is to make construction faster, safer and more efficient – whatever the chosen method,” explains Daniel Petrov, MD of Peikko SA. “We’ve renewed our focus on cast-in-situ connections, which are guaranteed to be reliable and highquality and save time on site.”

While precast construction means much of a project is prefabricated off-site, cast-in-situ requires concrete casting to happen on site. This means a multitude of products need to be inserted accurately and efficiently into the formwork before the concrete is poured. “This can be a lengthy process and has dire consequences if not done correctly – greatly impacting your bottom line,” explains Petrov.

A fresh take on traditional methods There are a range of cast-in-situ solutions to consider – typically for foundations, slabs, walls, columns, etc. These products are designed to make construction easier.

For example, for anchoring, Peikko offers HPM® rebar anchor bolts, PPM® highstrength rebar anchor bolts and its f lagship COPRA® a nc hor i n g c oupler s . To ensure these products are placed with the high precision needed for top-quality results, t he compa ny created a n installation template which ca n be used w it h a ny of the three solutions. “This is just one example of how we’re ta k ing a fresh look at traditional construction methods,” says Petrov.

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CASTING IN-SITU MAKES A WELCOME COMEBACK The product range extends to every requirement of a cast-in-situ project, adding renewed strength and robustness to tried and tested casting processes. For punching shear reinforcement, for example, Peikko has introduced a unique combination of horizontal and vertical studs (known as PSB® and PSB PLUS® systems) that increases capacity against punching shear failure of a reinforced concrete slab – with cost-efficiency in mind.

Getting the right support Beyond products, Peik ko also of fers superior support. Products are delivered to site on time, with clear communication throughout the sales process. A ftersa les suppor t means t hat customers get technica l adv ice and desig n g u ida nce at a ny time, allowing them to tap into decades of construction experience from the company.

“There are many strengths to Peikko’s cast-in-situ solutions, but the core benef its for the customer a re ava i labi l it y, efficiency and reliability. Onsite casting takes more labour and time, but with Peikko, projects stay on schedule,” says Petrov.

“While precast construction means much of a project is prefabricated off-site, castin-situ requires concrete casting to happen on site.”

(Above): The standard SMA and SMB connections enable connection of all rebars from 10-40mm.

(Left): Rebar couplers are used to create mechanical connections between ribbed reinforcement bars in castin-situ and precast concrete structures.

LOCALISED PRECAST MODULAR RESERVOIR CONSTRUCTION

Modular precast structures have increasingly become part of potable water infrastructure in numerous municipalities countrywide. Most notably, their use in highly demanding reservoir projects is changing the engineering landscape, replacing much of the complex and time-consuming cast-in-situ methods.

The system comprises a precast concrete roof, as well as a vertically pre-stressed and horizontally post-tensioned wall structure. However, the real innovation lies in the way it is constructed on site to ensure a watertight structure.

Fast and efficient roof construction A typical precast concrete roof structure comprises hollow-core slabs which are placed on precast concrete beams that, in turn, are supported by prefabricated columns.

The precast concrete columns are connected to the in-situ bases via cast-in components, or “column shoes”. These are secured to the hold-down bolts in the same manner as a conventional steel structure. Various column base configurations can be implemented to meet project-specific requirements and their designs consider a minimum safe bearing capacity of 200kPa at founding level.

The precast concrete beams are then installed onto the receiving columns. They are secured with dowels that protrude from the columns. This is followed by the installation of hollow-core slabs onto the beams, which are locked into place using tie-steel reinforcing and in-situ concrete inside their hollow cores. The stirrups protruding from the precast beams serve as a mechanical interlock to form a composite mechanism with the infill concrete.

Careful management for a complete system Prefabricated reservoir walls consist of precast concrete panels that have been designed to the required thickness. They have been pre-stressed during manufacturing and include cast-in sleeves which have been strategically positioned according to the design requirements for post-tensioning on site.

In addition to ensuring timely and accurate project completion, there are many more benefits to this system, including decongesting construction sites and enhancing health and safety, which are incorporated during the manufacture of the precast concrete reservoir system.

(Above): Developed for South African conditions, this precast modular approach to reservoir construction saves time and increases quality control.

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Address: 10th floor, Metal Box, 25 Owl Street, Milpark, Johannesburg Tel: 011 883 4627 | Email: isikhova@isikhova.co.za | www.isikhova.co.za

| INDUSTRY NEWS |

SAICE COMPETITION RECOGNISES CIVIL ENGINEERING RESEARCH EXCELLENCE The South African Institution of Civil Engineering (SAICE) recently joined forces with leading universities across the country to award civil engineering students for their research efforts. The SAICE National IP Showdown 2022 took place in March, when students presented their final-year research projects.

The event – which was sponsored by Sika, WorldsView, BVI, RIBCCS and AF Consulting – was hosted at SAICE House in Midrand, Gauteng and accredited for 0.2 CPD points. Students were invited to present their civil engineering university research and investigation project, which is part of the national curriculum for finalyear civil engineering undergraduates.

Through this project, students are required to select an issue which is current in the industry and then conduct research in accordance with pre-set deliverables.

Once the research is complete, the student teams present their findings to a panel of judges, which comprises both selected industry leaders and non-engineers. The

presentations are then adjudicated by: • Identifying whether teams have gained an in-depth understanding of the research project.

• Determining whether teams showcase adequate communication skills by presenting their work to a diverse audience.

• Exposing these top students to the industry and to key players within the industry.

The main objective of the event is to create a platform for winners from the various universities to compete on a national level.

Block Making Machinery

up to 300,000 bricks per 9-hours

Batching & Mixing designed to customer requirements

(Above): Brendon Gova from the University of Pretoria came second with his research, Assessing the Infiltration Characteristics of Urban Gardens.

This research can be used to inform the design of economical and effective urban hydraulic structures.

(Above): The winners for 2022 were Ashley Randall and Liam Macgregor from the University of the Witwatersrand for their research, The Effect of Vermicompost on the Water-Holding Capacity of Soil. Their study examined the potential to improve soil water retention using organic fertiliser, which is currently under-utilised in SA.

(Above): In third place was Mia Simon from Stellenbosch University, for her research, Using the Diffusion of Innovation Theory to Categorise Construction Industry Parties. Her research assessed innovative culture and leadership in the construction industry supply chain and identified obstacles to innovation such as technological limitations, training requirements and cost to implement.

Product Handling

manual to fully automated plants

Email: sales@panmixers.co.za Tel: +27 (0) 11 578 8700

| INDUSTRY NEWS |

(Above): Isothermal calorimetry is used to measure the heat generated or thermal hydration of cement to indicate its rate of reaction.

(Far left): Whatever is achieved in the cement laboratory can be closely assessed and tested in the concrete laboratory.

(Left): Mpume Mlalazi is the R&D manager at Chryso Southern Africa, responsible for Southern and Eastern Africa.

GREENING UP LOCAL LABS FOR HOMEGROWN

SUSTAINABLE CONCRETE SOLUTIONS South African materials, chemicals and additive producers are investing in green technologies to enhance their laboratory facilities in the quest to develop more sustainable construction materials.

Chr yso Sout her n A fr ica’s latest expansion is at its Centre of Excellence in Jet Park near Johannesburg – a cement laboratory in which the company has invested extensively.

In its quest to help customers generate more sustainable construction materials, Chryso Southern Africa has continued to enhance its laboratory facilities, even during the disrupted years following the onset of the Covid-19 pandemic.

Carbon reduction and global testing standards According to research and development (R&D) manager Mpume Mlalazi, in-

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(Above): Testing with the electronic air permeability instrument, designed to determine the specific surface area of cement.

| INDUSTRY NEWS |

vestments in the cement laboratory will continue during 2022 to ensure the latest tools are available.

“Much of our work in the cement laboratory is focused on the growing global concern to reduce carbon dioxide emissions from cement manufacturing,” says Mlalazi.

“We’re now also fully equipped to align with international standards in cement testing.”

The company’s other facilities include a research and development laboratory for new product formulation and evaluation, a concrete laboratory conducting physical tests to evaluate concrete properties, a quality control laboratory and a colour laboratory.

Regional footprint There are also satellite laboratories at the company’s Cape Town, Port Elizabeth and KwaZulu-Natal branches to support customers. Among the equipment recently acquired is an isothermal calorimetry and permeability tool, in addition to basic tools for cement-setting time, specif ic surface Blaine, pycnometry and cement compressive streng t h deter minat ion auxiliary equipment.

“Our cement laboratory works closely with cement industry players and supports

our customers with product development to find solutions for their ever-changing appl icat ions,” she says. “Of course, cement is the main contributor to concrete performance, so it’s vital that we understand exactly what impacts are achieved by the changes we can make.”

Driven to meet customers’ carbon reduction targets This is why its wide breadth of facilities – combined with its depth of expertise – is so effective, with its cement and concrete laboratories under one roof, she explains.

W hatever is achieved in the cement laboratory can be closely assessed and tested in the concrete laboratory.

“As experts in the field of admixtures, we have the necessary chemistry knowledge and products to help customers drive their sustainability agendas and meet their carbon reduction targets,” says Mlalazi.

She highlights that Chryso Southern Africa reinvests at least 4% of its sales revenues into research and development each year, emphasising that the laboratory capacity plays a strategic role in supporting customers’ key concerns in the future.

These include carbon emissions, clinker factors, cement performance and energysaving. The exciting projects underway in its cement laboratory include research into the potential for limestone calcined clay cement (LC3) to drastically reduce carbon dioxide emissions during the manufacturing process.

(Left): A two-place Vicat needle instrument used for the automatic determination of setting time of cement.

(Above): The Chryso Jet Park Concrete and Cement Laboratory technical team.

| INDUSTRY NEWS |

UNLOCKING DEVELOPMENT, OPPORTUNITY AND GROWTH WITH RENEWABLE ENERGY OPTIONS T he S A W i nd E ner g y A s s o c i at ion (SAWEA) and its sector stakeholders are advocating the industrialisation of the renewable energy sector to extrapolate the enormous potential across the value chain, thereby unlocking both the economic power of the renewable energy industry and delivering broader benef its to the people of the country.

The association has stressed the importance of managing the industrialisation of its sector responsibly by ensuring that components are localised on the basis of

their competitiveness and value-add.

To this end, SAWEA reiterates that predictable and continued procurement underpins any industrialisation policy and incentives to build more and better local capabilities, in order for the wind industry to compete with international markets, while supporting local manufacturers to become competitive for export markets.

Transformation takes evolving action “Transformation goes hand in hand with

“IRP2019 requires 3 600 wind turbines, underpinning the industrialisation plan and demonstrating a noteworthy opportunity for local employment and GDP contribution through annual production across the value chain.”

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the industrialisation of the wind power sector and market certainty is the most important aspect to building a local manufacturing industry. Hence, we require the Department of Mineral Resources and Energy to provide consistency, in line with the country’s energy roadmap, IRP2019, to kick-start industrialisation by upfront certainty on a number of Renewal Energy IPP Procurement Programme [REIPP] rounds and their primary local content framework,” explains Niveshen Govender, CEO of SAWEA. The country’s power sector procurement model started evolving over a decade ago, with major policy shifts. This has accelerated over the past 18 months, with the lifting of the cap on the newgeneration capacity requirement for a generation licence to 100MW and the government’s continued commitment to

| INDUSTRY NEWS |

rolling procurement. This is in line with the global uptake of renewable energy to increase energy security and achieve climate goals.

Yes… that’s 3 600 wind turbines IRP2019 requires 3 600 wind turbines, u nder pi n n i ng t he i ndu st r i a l i sat ion plan and demonstrating a noteworthy opportunity for local employment and GDP contribution through annual production across the value chain. By maximising the use of the current industrial capacity to supply materials and components to the sector’s demand areas, additional investments in capacity and capability will be stimulated.

“We continue to support the various stakeholders, including the government, labour, civil society, researchers, industry contributors and other advisory groups, which are currently drafting the South African Renewable Energy Masterplan that addresses exactly how we can industrialise the renewable energ y value chain in our electricity sector to enable inclusive participation in the energy transition, serving the needs of society and contributing

to economic revival,” says Govender.

SA has been relatively successful in establishing local manufacturing to serve the utility scale wind market in the past through the diverse representation of OEMs. However, while the renewable energ y market is no longer nascent, the renewable energ y manufacturing component can still be considered as emerging. This was exacerbated by the hiatus in procurement in REIPP regarding the signing of Bid Window 4, resulting in the loss of local civil engineering capacity, which now requires some level of ramp-up to fully capacitate the sector again, in line with the government’s resumption of the renewable procurement programme.

Framework for the future “Our industry needs to understand, harness, accelerate and maximise localisation to move towards industrialising renewable energ y in SA. To do this, we’ll work alongside and within the framework and mechanisms, ensuring that this transition is managed responsibly and can deliver true value and benefit for our industry, the country and its people,” says Govender.

| INDUSTRY NEWS |

“Such training has been provided by the School of Concrete Technology for well over 60 years and its consulting division is constantly involved in the writing of standards, publications and assessment of latest technologies.”

(Right): Pigmented concrete bus lanes were innovatively specified for Cape Town’s MyCiti public transport system.

Concrete will play an essential role in the government’s plans to implement long-awaited infrastructural projects this year, says John Roxburgh, senior lecturer at Cement & Concrete South Africa’s School of Concrete Technology (SCT).

Roxburgh says concrete is the most v ital building material to create the infrastructure to sustain South African urban and rural settlements, as well as the road networks that link these areas. “Apart from being the essential material to erect the presidentially-proposed new ‘smart cities’, concrete is also essential for housing, dams, bridges, warehouses, roads, airports, water and sewage treatment plants, to name just a few important civic facilities. It's therefore essential that local government’s

CONCRETE SKILLS CRITICAL TO UNLOCK PUBLIC-SECTOR GROWTH STRATEGY staff are trained in all facets of concrete construction and design,” says Roxburgh.

Such training has been provided by the SCT for well over 60 years and its consulting division is constantly involved in the writing of standards, publications and assessment of latest technologies.

(Above): Concrete is the essential component for local government mass housing settlements throughout SA.

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Concrete training across the range The SCT 2022 Training Programme, now available, includes courses on a wide range of topics starting from a basic introduction to concrete and continuing to cover the role of concrete in housing, concrete practice, training for ready-mixed concrete

| INDUSTRY NEWS |

and batching plant personnel, concrete industrial floors on the ground, concrete road design and construction, as well as high-technology training that includes the globally-respected Advanced Concrete Technology diploma course with examinations set by the Institute of Concrete Technology in London.

Suc ces s f u l st udent s for a l l SC T courses receive certificates of attendance/ competence and Continuing Professional Development (CPD) points are awarded on certain courses.

Roxburgh says two courses to be offered by the SCT in 2022 should be strongly considered by SA municipalities: “SCT20 Concrete Practice” and “SCT30 Concrete Technology”. Both regularly attract strong enrolment, calling for several presentations every year.

“The four-day ‘SCT20 Concrete Practice’ course is excellent for those applying concrete technology on site such as foremen, supervisors and staff responsible for quality assurance. Successful completion

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

school’s training in future, which means local government in even the most remote parts of the country can now enrol staff for training,” says Roxburgh.

For further information and access to the SCT 2022 Training Programme, tel: (011) 315 0300 or e-mail: rennisha.sewnarain@ cemcon-sa.org.za

Online training and live classes The SCTwill continue to run its successful online e-learning courses in 2022, but will also offer select classroom-based lecture courses in Midrand, Durban and Cape Town while Covid-19 lockdown restrictions permit. “The live classes will be kept small and high demand for specific courses will be met by scheduling more presentations. However, the online platform and self-study courses are here to stay, as they align themselves with modern trends in remote learning and increased access to both data and smart delivery devices. E-learning and its associated benefits will form an integral part of the

(Above): John Roxburgh, senior lecturer at the SCT.

TECHNOLOGICAL INNOVATION IN THE CONCRETE INDUSTRY STARTS WITH MAP PRODUCTS. • • • • • • • • • • • • • • • • • • • Learn more at mapei.co.za Tel: +27 11 552 8476 Email: info@mapei.co.za

Precast concrete plasticising admixtures Ready-mixed concrete plasticising admixtures Extended workability polymers Set retarding admixtures Hardening accelerators Viscosity modifying admixtures Form release agents Synthetic fibres Pozzolan-activity mineral additions Permeability-reducing admixtures Water-repelling admixtures Anti-washout admixtures Expanding agents Drying shrinkage-reducing admixtures Clay mitigating admixtures Pumping aides Air entraining and foaming agents Concrete rescue packs Evaporation-retarding admixtures

| PROJECTS |

Beit Bridge border upgrade’s massive

DEMAND FOR CEMENT In a landmark project that promises to transform the experience of passing through the Beit Bridge border between South Africa and Zimbabwe, leading contractor Raubex is well advanced in constructing three new immigration facilities. The cement for the project’s 125 000m2 of roads and parking area is

coming from AfriSam’s Roodepoort plant, 550km to the south.

The new borderpost at Beit Bridge, one of Zimbabwe’s f irst public-private partnerships, is making good progress toward completion by JSE-listed contractor Raubex, on behalf of its client Zimborders Consortium.

(Above): The project as a whole requires 10 000 tons of high-strength R42.5 cement from AfriSam, supplied from its Roodepoort plant near Johannesburg.

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Three phases of the project When completed, the facility will provide three new immigration facilities, each custom-designed to speed up the flow of traffic, according to Raubex construction manager Herkie Sandenbergh. The first area, dedicated to freight trucks, has already been handed over and processes approximately 500 trucks a day. Currently underway is the second phase, which is focused on bus transport and will be completed this month. The third phase will be the facility for light traffic, which will

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Avoid concrete strength delays

this winter.

The second phase – the facilities for bus transport – is currently underway and is on track for handover to the client this month.

be handed over in November this year.

“Each stream w ill have its own terminal building where all customs and immigration documentation will be dealt with, thereby streamlining the processes by applying specific expertise in each area,” says Sandenbergh. He adds that there is considerable related infrastructure around the town of Beit Bridge which is also included in the scope of work. This includes an 11,5 million-litre reservoir with associated pipelines, an oxidation dam for sewage treatment, a f ire station, an animal quarantine facility and a new staf f village for borderpost personnel.

Cement supplier up to the task As a key partner in the project, AfriSam has supplied some 7 000 tons of its high-strength R42.5 cement from its Roodepoort plant near Johannesburg.

T he company w i l l have del ivered around 10 000 tons of bulk cement by the time work is completed – delivered

in 34-ton tankers.

Adele Wentzel, A fr iSam’s sa les manager: manufacturing for Gauteng, says the distance from site and the complexities of border crossings have been among the challenges to be overcome.

“The AfriSam team has been working closely to ensure consistent quality and on-time delivery, while complying with the various customs requirements at the border,” says Wentzel. “Our close co-ordination – combined with daily interactions with site – have kept the project proceeding well.”

She notes that congestion at the border – which delayed trucks for up to a week – was a particular challenge in the early stages. “Our success to date has certainly built constructively on our long relationship with Raubex,” she says.

(Left): As activity reaches its height, there are about 1 160 people on site, with over 570 labourers from the local area around Beit Bridge and almost 350 skilled Zimbabweans employed.

ACCELERATORS FOR COLD TEMPERATURES As winter approaches, the colder ambient temperatures can cause delays in concrete strength development as well as finishing aspects.

Rest assured, this challenge can be easily overcome using CHRYSO’s winter accelerator admixtures. za.chryso.com

| PROJECTS |

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| PROJECTS |

Jacking pylons at

MSIKABA BRIDGE

The Msikaba Bridge Project on the new N2 toll road between Port Edward and Mthatha recently achieved an engineering milestone as the legs of the bridge’s south pylon were hydraulically jacked apart.

The 580m-long stay-cable bridge – which will span the 198m-deep Msikaba Gorge – forms part of the N2 Wild Coast project being undertaken by SA National Roads Agency Ltd (Sanral) and is under construction by the CME joint venture, a partnership between Concor Construction and MECSA Construction.

These two legs make up the first 20m of the inverted Y-shaped pylon, says CMEJV project director Laurence Savage, and are

(Above): These two legs make up the first 20m of the inverted Y-shaped pylon and are built without any lateral support as free cantilevers.

(Left): The total movement of the pylon after jacking totalled 23mm at a force of 1 750kN, which was within the design parameters.

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built without any lateral support as free cantilevers. Once completed, four lanes of vehicles and a pedestrian walkway on either side will pass beneath these legs at the start and end of the bridge deck.

“The jacking apart of the legs countered the bending moment at the bases of the cantilever legs,” says Savage. “In layman’s terms, the jacking eradicated the effect of the legs bending towards each other. As engineers would see this, the legs are effectively vertical due to the jacking process.”

Anchoring and supporting six storeys of concrete The bridge includes two pylons that will stand 128m high on each side of the gorge; the pylons support the bridge deck using a network of 34 cable tendons strung through their upper reaches.

“These cables then run from the top of the pylons back into anchor blocks located 100m to the rear of the respective pylons,” says Savage. “Each of the four anchor blocks is made up of over 1 600 tons of structural reinforced and mass concrete and extends 17m – the equivalent of six storeys of a building – into the ground.”

He explains that the lateral support was installed on the sixth lift of the pylon structure, after 520m³ of concrete had been poured to reach a height of 20m.

“Two sets of hydraulic jacks were installed parallel to each other and a jacking force of 1 750kN applied to the two pylon

“The bridge includes two pylons that will stand 128m high on each side of the gorge; the pylons support the bridge deck using a network of 34 cable tendons strung through their upper reaches.” legs to counter the bending moment for the free-standing cantilever legs,” says Savage.

“To achieve the required force, the two 150-ton hydraulic jacks were loaded to 90 tons, developing a pressure of 41MPa. The jacking was done at 5MPa intervals and

deflections of the structure were monitored using dial gauges and surveying.”

The art of dissipation He notes that a key consideration was the punching force on the flat face of the pylon legs due to the jack load. This also dictated the size of the bearing plates affixed to the inside of the legs, enabling a dissipation of the force across the appropriate surface area. This prevented any damage to the str ucture due to loading of the concrete surface.

“The jacks only have a 50mm stroke, which required the installations to be exact, as the 41MPa pressure had to be achieved before the jack ran out of stroke length,” he explains. “The base plates were installed on the pylon leg structure with 29mm non-shrink grout minimising the use of the stroke length.”

(Above): The jacking was done at 5MPa intervals and deflections of the structure were monitored using dial gauges and surveying.

(Left): The jacking apart of the legs countered the bending moment at the bases of the cantilever legs.

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After the lateral support was aligned and seated, a grout biscuit was cast which served two key functions. Firstly, it absorbed any tolerances in the installation after the initial base plate installation and secondly, it assisted with the removal of the lateral support. Breaking out the grout biscuit released the pressure in the lateral support, once the seventh lift was cast and the legs permanently locked together.

Temperature and force “The temperature of the pylon structure and lateral support was measured to ensure an average of 22°C, to limit any unforeseen changes in force due to changes in the temperature during the construction cycle casting lift seven,” says Savage. “The lateral support was wrapped in a 25mmthick thermal blanket to limit temperature change movements and any resulting changes in prop forces.”

The lateral support was locked into place using a two-part system: the locking

ring on the hydraulic jack and the locking ring on the super-shore jack housing.

The preparation for the jacking took three months of planning and analysis, while the set-up was conducted over nine days. The actual jacking process was

completed in less than eight hours from commencement.

Sav a ge conc ludes t h at t he tot a l movement of the pylon after jacking totalled 23mm at a force of 1 750kN, which was within the design parameters.

(Above): The lateral support was installed on the sixth lift of the pylon structure, after 520m³ of concrete had been poured to reach a height of 20m.

| PROJECTS |

Casting innovations

IN ROSEBANK PROJECT (Above): The façade itself is a unitised system which is less labour-intensive to install and did not require a full façade scaffold for installation.

(Above, from top): Warren Mills, Concor site agent. Separating waste at source ensured that rubble, wood, steel and plastic were sorted into dedicated skips.

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Applying innovative construction methods and its wel l-established qua lit y and scheduling systems, Concor has met another tight deadline with the handover this February of the Ikusasa building in Rosebank, Johannesburg.

The building – which features four storeys above ground and three basement levels – is part of the popular Oxford Parks mixed-use precinct in Johannesburg and will be occupied by Anglo American Global Shared Services (AGSS). According to the Concor site agent, Warren Mills, the company’s core team was required to manage around 70 specialised subcontractors, ensuring the most efficient deployment of resources to meet the project’s demanding time-frames.

Larger foundation piles eliminate need for concrete bases “Among the innovations we employed to cut the construction time was the use of larger foundation piles,” says Mills. “This meant that there was no need for concrete bases or excavating around each pile. Instead, the design allowed the columns to be cast over the piles.”

Some 115 piles were cast, with columns spaced on an 8,4m x 8,4m grid to hold the suspended concrete slabs. By expediting this part of the contract, Concor could give early access to wet trade contractors like bricklayers and tilers, as well as to the installers of the unitised façade panels. “This allowed us to make rapid progress towards the external works and the internal fit-out,” he says.

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Another innovation was to back-prop on just two levels, rather than the traditional three. This also allowed earlier access to the lower floor plate, to initiate brickwork and “first-fix” services such as floors, ceilings, electrical supply cables and water pipes.

“The result was to facilitate beneficial occupation for the tenant, giving them early access in a phased approach to prepare the working areas with furniture and other fixtures in time for employees to start work,” says Mills.

The building’s four levels make up over 7 500m2 GLA, while the three basement levels cover more than 10 300m 2. The structure consumed about 8 700m 3 of concrete and over 8 00 tons of reinforced bar.

Recycled materials a feature In line with sustainable building practice, a priority on the site was reducing, reusing and recycling construction waste.

This included separating waste at source, ensuring that rubble, wood, steel and

Applying innovative construction methods and its wel l-established qua lit y and scheduling systems, Concor has met another tight deadline with the handover this February of the Ikusasa building in Rosebank, Johannesburg.

T he bu i l d i n g – w h ic h fe a t u r e s four storeys above ground and three basement levels – is part of the popular Oxford Parks mixed-use precinct in Johannesburg, and will be occupied by Anglo American Global Shared Services (AGSS). According the Concor site agent Warren Mills, the company’s core team was required to manage around 70 specialised subcontractors, ensuring the most efficient deployment of resources to meet the project’s demanding timeframes.

(Above): Warren Concor was able to give early access to the wet trade contractors.

plastic were sorted into dedicated skips. By preventing contamination of different waste streams, waste could be more efficiently and cost-effectively recycled.

Ikusasa is Concor’s first six-Green Star

building in terms of the Green Buildings Council SA Green Star rating. In recent years, the company has completed a number of award-winning buildings in the Oxford Parks precinct.

• Tel: + 27 11 822 2320 • Fax: + 27 11 822 2354 • e-mail: cindy@ashak.co.za

Larger foundation piles eliminate onding airs need for concrete bases p crete B • Con ete Crack Re ents g r A c n e o leas • C Agents ete Re ir Mortars r g c in n d o s n C (Left): A two-place o needleAinstrument • BVicat nchor used for • e Repa mical oncret the automatic determination • Che of setting time of cement. • C

• • • • • • •

unds Compo s g in r u C ive Adhes Epoxy out r G Epoxy lants ea S t in o J routs rink G s h S Non air st Rep Pre Ca oofing Pr Water

6574 Ashak Constrctn 1/2pg ad MAY’22 Precast MAG

For Quality Release Oils Formulated For Specific Apllications!

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| TECHNICAL |

Release agents, when properly used, aid in the stripping process, assist in producing sound, defect-free concrete surfaces, simplify form-cleaning and increase the working life of quality form surfaces.

There are two main categories of form release agents: • Barrier – those that provide a physical barrier between the form and the concrete (such as petroleum-based products, soaps, synthetic resins and waxes).

• Reactive – those containing fatty acids or other ingredients that react with the free lime in fresh concrete to produce a metallic soap interface between the form and the concrete (such as proprietary products and vegetable oils that are typically found in petroleum-based carrying agent products).

Applying release agents Release agents should be applied to a clean form before the reinforcement has been placed to reduce the likelihood of inadvertently applying it to the reinforcement. If the release agent does come into contact with reinforcement, it should be wiped clean before placing the concrete.

The amount needed to effectively coat a form is only about 0,0127cm thick. The (Below): The amount needed to affectively coat a form is only about 0,0127cm thick. The actual cover thickness will depend on the application method and viscosity of the product, which are related to the ambient temperature. Typically, the colder it is in the plant, the thicker, or more viscous, the release agent will be. The warmer the plant, the thinner or less viscous it will be. Different measures can be taken during the application process to account for changes in material temperature (viscosity) throughout the year.

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THE RIGHT WAY TO APPLY RELEASE AGENTS

actual cover thickness will depend on the application method and viscosity of the product, which are related to the ambient temperature. Typically, the colder it is in the plant, the thicker, or more viscous, the release agent will be. The warmer the plant, the thinner or less viscous it will be.

Different measures can be taken during the application process to account for changes in material temperature (viscosity) throughout the year.

| TECHNICAL |

(Left): When applying a release agent, it is best to follow the manufacturer’s instructions. When too much form release is used, it is not only wasteful and inefficient, but leads to a number of other associated problems with the finished product. Proper training is crucial. As a rule of thumb, less is better.

(Above): Remove dust and loosened concrete residues from the formwork.

(Below): Wear appropriate safety equipment: long sleeves, pants, safety glasses and suitable gloves.

Spraying Spraying is probably the most efficient and common method for applying release agents. Keep the wand moving when applying form release. Broad-nozzle spray tips have been found to give the thinnest and most uniform cover. It should be noted that as the temperature drops and viscosity increases, the spraying pressure should be increased and the nozzle orifice size reduced. As temperatures rise, reduce pressure and increase the nozzle size. It is a good practice to soak or mop up any puddles that may have formed at the bottom of the form. Remember: less is better. Only through experience and training will you learn what works best for your plant’s production line.

Caution: Fatty acids will react with brass, bronze, aluminium, grey ductile and malleable iron and mild steel, as well as some petroleum-based products used for making blockouts and other embedded items. It is best to use stainless steel, nickel or plastic for your spraying systems and to test for possible reaction of embedded materials prior to full implementation.

“Remember: less is better. Only through experience and training will you learn what works best for your plant’s production line.”

Dipping Automated dipping systems are fast, labourefficient and ensure complete coverage.

Excess material will usually drip back into a holding tank, reducing material waste.

The application coat is often thicker than necessary. However, this again creates the potential for future problems.

Swabbing and painting Swabbing and painting by hand is an acceptable application method, with the benef it of eliminating the majority of airborne particulate. On the negative side, applications tend to be thicker than necessary, leading to wasted material and the potential for additional problems.

Wiping Wiping is often the method of choice for architectural precasters concerned with a blemish-free surface. Wiping on release agents with a sponge or rag will normally result in the thinnest coating, but it is very labour-intensive.

Seasoning Reactive form release agents (the most commonly used release agents in precast and pipe production) typically contain fatty acids. Fatty acids are mild acids composed of animal fats and vegetable oils. These fatty acids have a natural affinity for metal.

They react with metal to form a protective barrier, which is a coating of metallic oleate.

This process is known as seasoning. The protective layer prevents further application of fatty acids from migrating to the metal of the form and allows the fatty acid to remain on the surface of the form to react with the free lime on the surface of the casting.

Seasoning serves two purposes. First,

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it enhances the easy separation of the form from the castings. Second, it enables free air to rise more easily on the vertical surfaces of the castings, resulting in fewer surface defects.

Seasoning of forms is a ver y basic requirement to help minimise the amount of labour involved when forms are stripped or pipes are tipped out. If forms, pallets and headers are properly maintained, less labour cost and better-looking castings are the end result.

New forms, pallets and headers will frequently arrive with a protective coating on them to help prevent rusting in transit or until the forms are sold and delivered. In order to season these forms, the protective coating can be removed with solvents or grinding and the form release applied liberally, allowing it to set for a minimum of four hours. A 24-hour period is better, as it allows more seasoning to take place.

Also, forms that are exposed to the sun will season more quickly, as higher temperatures increase the reactivity with the metal forms and rings.

Care of forms and rings At times, you may be storing forms inside or outside for short or long periods. Release agents can be used to protect this vital equipment from damage. For short- or longterm storage, a good-quality petroleum solvent-based form release can be used by applying a liberal coating on the form.

If the forms are stored outside, even for a short time, a quick walk-by is often necessary to ensure that the form release has not washed of f from rain. If any evidence of rust is present, apply another coat of the form release on the forms and rings as quickly as possible.

A biodegradable form release is preferred, as over-application is desired and some of the material will end up on the ground.

Identifying potential problems Concrete is a highly variable material because it is comprised of raw materials that potentially have a lot of variability. It is often difficult to pinpoint exactly what causes a problem because it may be a combination of a number of factors. The following are two examples of common problems often associated with excessive form release agent coverage:

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(Above): Spray vertical surfaces first.

(Above): Walk backwards when spraying the formwork, to prevent leaving footprints.

• Staining has been linked to the use of excessive release agents and the use of dirty forms. Dirt, dust, rust or grease can easily be transferred from a dirty form to the finished surface of the concrete product. Once a form has been properly cleaned and coated with release agent, proper measures should be taken to minimise the potential for dust and debr is to collect on the form before casting.

• Excessive bugholes occur when barrier-type release agents are applied too heavily. Barrier-type release agents tend to encapsulate free air along the vertical sidewalls, which leads to surface defects. In contrast, the metallic soap formed when using a reactive release agent allows the free air on the vertical walls to rise more easily to the surface.

Proper vibration practices also reduce bugholes. The potential for bugholes and staining can be reduced by selecting

an application method that produces the thinnest coat of release agent in accordance with the manufacturer’s recommendations. Release agent should not be allowed to collect and pool in the forms. Applying a thin coat, wiping up puddles and avoiding contact with reinforcing steel greatly improves the odds of producing a defect-free concrete product.

Disclaimer This publication is designed to provide accurate and authoritative information. However, the National Precast Concrete Association and Isikhova Media, the publisher of Precast magazine, do not guarantee the validity or accuracy of any data, claim or opinion appearing in this publication. If engineering, legal or other professional services are required, the services of a competent professional should be obtained.

The National Precast Concrete Association and Isikhova Media do not assume and hereby disclaim liability to any person for any loss or damage caused by errors or omissions in this publication, regardless of whether such errors result from negligence, accident or any other cause whatsoever.

| FEATURE |

GETTING THE MOST OUT OF PRECAST HYBRID CONSTRUCTION METHODS What is hybrid concrete construction?

Hybrid concrete construction is the combination of precast and in-situ concrete.

Different materials are used according to their strengths and weaknesses to provide simple, buildable and competitive, high-quality structures that offer consistent performance.

Hybrid concrete construction can incorporate all the benefits of precasting (eg form, finish, colour, speed, accuracy, pre-stressing, high quality, assured covers and dense and properly cured covercrete) with all the benefits of in-situ construction (eg economy, flexibility, malleability, continuity and robustness).

The precast and in-situ elements can act independently or in combination. In addition, a structural element can comprise both precast and in-situ concrete working compositely. Numerous hybrid precast and in-situ systems are available and some are used widely.

Structural action of hybrid concrete construction 1. Independent action Precast cladding adorns mainly insitu framed buildings. Simple repetitive portions of a structure may naturally lend themselves to precast construction, whereas more complicated, less accessible sections may lend themselves to

in-situ construction.

2. Combined action Precast units can directly replace insitu elements, eg stair flights or hollowcore floor units within in-situ frames.

Units can be used as permanent formwork, substituting for and largely obviating the need for conventional formwork. This brings the advantages of factory-engineered concrete to site.

3. Composite action In-situ concrete toppings are often added to precast floors for greater strength, stiffness and robustness. In-situ floor slabs can be cast on top of precast downstand beams to give highly efficient, composite T-beams.

Benefits of using hybrid concrete construction • Time and cost of construction Construction of hybrid concrete structures provides good quality and greater speed during construction, making it more economical. Thus, cost of hybrid concrete construction is less than normal construction.

• Buildability of hybrid concrete Hybrid concrete structural elements are manufactured by a skilled workforce. Thus, quality of structural members is good. The use of this concrete also helps to reduce time of construction,

as design and building decisions are taken before the start of construction.

• Safety during construction As most of the hybrid concrete structural members are constructed at the factory, it offers more safety to the workforce during the construction process. The plan for safety procedures for installation of these members can be made based on site conditions and in advance, reducing the chance of accidents at the construction site.

“Precast units can directly replace in-situ elements, for example stair flights or hollow-core floor units within in-situ frames.”

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(Above): Twisted reinforcing mesh is placed between slabs.

REINFORCING CONCRETE SLABS

REVISITED In modern monolithic construction, the priority task is to reduce the material consumption of the structure by applying technological methods for the rational use of materials, as well as reducing labour costs for the entire construction period.

The installation of monolithic reinforced concrete floor slabs is an important and necessary stage in the construction lifecycle. The disadvantage of such a floor slab is the high own weight of the structure.

Because of this, it is necessary to strengthen all the supporting elements of the building frame. This need leads to an increase in the consumption of materials, labour costs and, as a result, an increase in financial costs for construction. Based on this, effective constructive and technological solutions for lightweight precast monolithic floor slabs have recently been developed.

Lightweight strength The use of lightweight expanded polystyrene inserts in the thickness of reinforced concrete floor slabs leads to a decrease in their own weight and, as a result, a decrease in loads on f loor slabs, vertical structures and

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foundations, which makes it possible to reduce the material consumption of these structural elements. The use of permanent formwork allows one to reduce labour costs for assembly and disassembly of the formwork. Thus, due to the use of permanent formwork and expanded polystyrene inserts, the installed structure will immediately have an increased degree of constructionreadiness which, in turn, will lead to savings in labour costs and other resources. The aforementioned determines the relevance of further scientific research and pre-design developments aimed at saving resources in the installation of floor slabs by applying innovative solutions in their constructive and technological directions.

To replace prefabr icated housing construction, in the past two to three decades, monolithic reinforced concrete frame structural systems have become most widespread due to their increased rigidity and ease of production of reinforced concrete work in collapsible industrial formwork systems directly at the construction site.

At the same time, such technologies also have a number of significant disadvantages,

“The use of permanent formwork allows one to reduce labour costs for assembly and disassembly of the formwork. Thus, due to the use of permanent formwork and expanded polystyrene inserts, the installed structure will immediately have an increased degree of construction-readiness.” primarily their increased labour-intensity and long terms of work complet ion.

Therefore compromised precast monolithic constructive technological systems of lowrise civil construction are becoming more widespread.

Limestone blocks The use of inserts made of limestone (shell rock) blocks as a local material for the construction of low-rise buildings can also be considered. This simply requires replacing the prefabricated precast reinforcing formwork block with two elements that allow their manufacture under construction (Above): Precast monolithic constructive technological systems of low-rise civil construction are becoming more widespread.

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conditions – a spatial reinforcement cage and a formwork base board, on which the mentioned reinforcement cage was mounted with a gap that provides the required thickness of the concrete cover.

Another possible and practical way of reducing own weight of flat floor slabs in a precast monolithic building frame is the replacement of part of the concrete with plastic inserts of various shapes: balls and similar bodies of revolution (bubble deck technology), rectangular parallelepipeds (nautilus technology), etc. In their projects, the developers show 35-50% of savings in reinforced concrete, with the resulting other improved technical and economic indicators (cost and timing). Analytical studies of comparative streng th and deformation properties of such systems in comparison with a solid reinforced concrete slab have also been carried out. However, such studies have not been brought to the level of assessing the economic efficiency of technology implementation at specific sites.

Hollow forms The possibility of using hollow forms in the installation of monolithic foundations is also

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“A further resource-saving development is the use of a slab precast monolithic floor structure resting upon all four sides.” considered. An original construction of a flat monolithic floor slab was synthesised and patented which has distinctive features, resulting in a reduction of the consumption of reinforced concrete by taking into account the actual work of the section of such reinforced concrete structure.

The specified technical result is achieved by the fact that the construction of a monolithic floor slab, having an upper and lower wire mesh, is located in horizontal planes, between which there are rows of frames alternating with inserts. The space between these inserts is filled with concrete and the inserts themselves are made with detachable legs, consisting of at least two parts which are spatial volumetric bodies of revolution, the shape of which closely resembles a pear.

Permanent formwork Another option is reinforced concrete interf loor f loor slabs using permanent formwork of precast monolithic bearing beams, interspersed with a variety of inserts, and replacing reinforced concrete with a lighter construction material, such as expanded polystyrene, topped with a thin reinforced concrete slab which is then concreted. This leads to significant savings in heavy concrete and reduction of own weight of the floor slab, thereby reducing the calculated constant load from the floor slab for which the supporting structures are designed and lower costs of finishing and insulation work of the resulting ceiling surface. An example of such a system is the use of permanent formwork made of fibreboards with expanded polystyrene inserts or fibreboard (arbolite) boards.

Developers and manufacturers call such slabs chip cement. Similar slabs based on wood chips can also be produced using the carbonate hardening dolomite binder developed by Russian scientists.

(Below): An example of monolithic construction methods using permanent formwork.

In addition to saving material and labour costs during the production of the floor slab itself, one achieves a ceiling surface that usually only requires finishing, which is certainly a more technological solution, since it does not require time-consuming wet plaster or widespread cladding with gypsum plasterboard sheets. However, this structural and technological system usually provides for the support of the floor slabs only on the longitudinal bearing walls, ie it is used mainly as a beam.

A further resource-saving development is the use of a slab precast monolithic floor structure resting upon all four sides.

In this version of the system, the combination of a monolithic reinforced concrete belt and a precast monolithic floor slab according to the improved Velox technology resting upon all sides will provide a more significant synergistic effect of saving materials, especially heavy reinforced concrete. To solve this problem, a precast monolithic reinforced concrete floor slab is proposed, consisting of conjointly made slabs and beams with reinforcement, located in two directions and forming a mesh with a side ratio of less than 2. In this case, the reinforcing cages of the beams have a triangular shape in a plane perpendicular to their longitudinal axes and the reinforcing mesh of the slab is connected to the reinforcing cage of each beam, which has a triangular shape. Between these beams there are cells not filled with concrete.

Using the proposed floor slab structure, even in the technological process of its manufacture, it will be possible to obtain a constructive system that ensures the performance of load-bearing, insulating and finishing functions without the need for the subsequent implementation of most timeconsuming and heavy f inishing and insulation works.

This is ensured by a prefabricated hermetically sealed continuous permanent formwork. The proposed clamps simultaneously play the role of rigid connections of individual shields in a geometrically stable and unchangeable system.

Thus, the arranged structure of the precast monolithic floor slab will have an increased degree of constructionreadiness immediately after its manufacture in one complex technological process. Consequently, the proposed technology intensifies the complex construction process, reducing its labour-intensity and cost.

It is possible to confirm the stated assumptions by means of experimental and theoretical studies of the comparative efficiency of the presented constructive and technological solutions for interfloor precast monolithic floor slabs. To confirm the advanced hypothesis about the effectiveness of the presented scientific and design developments of precast monolithic floor slab structures, it is necessary to simulate the operation of two floor slabs – the original solid reinforced concrete slab and an innovative slab with a permanent formwork and expanded polystyrene inserts. Computer modelling of the stress-strain state with the design of the structure and principal reinforcement must be carried out in the LIRA-SAPR computing complex; it is also necessary to perform calculations and assess the technical and economic indicators of the proposed technologies.

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| FEATURE |

Concrete is the world’s most widely used construction material – and also one of its greatest contributors to greenhouse gas. The root cause is cement production, which alone accounts for approximately 8% of global CO₂ emissions. At this rate, successful strategies to lower concrete carbon output are especially significant.

MCI® Technology is a simple, but powerful strategy that helps the construction industry take a pivotal step towards a smaller carbon footprint.

Ashraf Hasania, Cortec’s MCI® technical sales and product manager, who holds degrees in civil and environmental engineering, explains the common-sense logic: “Increasing the service life of concrete structures using durable materials can reduce the need for demolishing old structures and building new ones. It can also lead to less need for major repairs. This lowers the carbon footprint of concrete structures and promotes sustainable practices.”

Rust, rebars and cracking The way MCI® helps concrete structures last longer is by attacking one of the biggest enemies of concrete durability: corrosion of metal reinforcement. As rebar rusts due to carbonation, chloride exposure and other environmental conditions, it expands and puts pressure on the concrete cover. This leads to cracking, spalling and a vicious cycle of further exposure to corrosives and additional damage. Based on salts of amine carboxylates, MCI® Technology interrupts this process by migrating through the concrete pores to form a protective molecular layer on the rebar surface to delay and reduce corrosion.

Service life models and lab and field studies have shown that MCI® can increase service life by three to four times. This translates into a comparable reduction in concrete’s carbon footprint.

Treat now, treat later, but always treat MCI® can be used at any stage in a structure’s life-cycle, but the best course to pursue is early treatment. “Sustainability in construction starts early in the process,”

SUSTAINABILITY THROUGH EXTENDING ADMIXTURES (Above): Bio-based admixtures can mean carbonpositive results, with self-healing properties.

(Left): Regular treatment with life-extending admixtures allows for structural strengthening from surface to core.

embedded rebar in sound concrete, or to even out corrosion potential and interrupt the problematic ring-anode/halo effect between new patch repairs and old concrete.

advises Hasania, “specifically in the design phase with careful selection of construction materials and concrete mixes.” Ideally, this includes the choice of MCI® concrete admixtures, which can be added to new concrete at the ready-mix plant or construction site. In contrast to calcium nitrite admixtures, MCI® admixtures have a low dose independent of chloride loading and do not negatively affect concrete mix properties. Existing structures can be treated with MCI® in the form of surface-applied corrosion inhibitors (with or without water repellent) and repair mortars.

Once applied, the MCI® molecules migrate through concrete pores to protect

“This use of renewable resources can help the project earn credits toward LEED certification, while adding a more sustainable image to the structure and builder.”

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PRECAST | ISSUE TWO | 2022

Renewable and safe In addition to the main goal of helping concrete structures last longer, MCI® Technology offers other attractive features.

For example, MCI®-2005 is a USDA-certified bio-based product that contains 67% USDA-certified bio-based content. This use of renewable resources can help the project earn credits towards LEED certification, while adding a more sustainable image to the structure and builder. Another attractive feature is the low toxicity of MCI® products, many of which are certified to meet NSF Standard 61 for use in potable water structures.

Considering the costs of construction and rebuilding alone, the benef its of extending concrete service life are clear.

Add to this the ripple effect of decreasing the amount of new cement needed to repair and replace old structures, and the advantages of MCI® Technology go even further – helping the construction industry take major steps towards a smaller carbon footprint and a more sustainable future.

| FEATURE |

A new state-of-the-art brick factory recently came online in Driefontein, opening up the southern African market further and enhancing its ability to supply new publicsector projects.

Announced by Corobrik at the SA Investment Conference in Sandton in 2019, the investment is paying off handsomely, with the new Kwastina (“Home of the Brick”) factory in full production since late March.

The R800 million investment in the state-of-the-art manufacturing facility has gone hand in hand with a further R200 million earmarked to expand Corobrik’s concrete operations in KwaZulu-Natal.

“Kwastina produces clay facebricks, while the concrete operation’s targeted at the plaster brick and block market,” explains CEO Nick Booth.

Home of the Brick Kwastina is fully automated, from mixing the raw materials to the end product.

Capable of producing 100 million bricks a

BOOST FOR CLAY AND CONCRETE BRICK AND BLOCK MARKET year, the new factory will easily be able to meet larger-volume orders. In a first for the local market, it will also have the flexibility to produce small quantities of bespoke products for the architectural segment.

“What makes this initiative so exciting is that it allows us to compete anywhere in southern Africa, landing product in regions traditionally not in Driefontein’s market, as the new factory is more cost-effective,” says Booth.

(Above): Kwastina is the most technologically advanced brick factory in southern Africa.

The Kwastina factory represents an R800 million investment in the region’s construction market.

Touted as the most technologically advanced and environment-friendly brick manufacturing plant in Africa, Kwastina is testament to Corobrik’s commitment to constant innovation. “It’s an acknowledgement on our part that we need to progress and make the changes that will keep us relevant for the next 100 years,” says Booth.

Latest tech hard at work The project was completed on budget, despite a three-month delay due to the Covid-19 hard lockdown in 2020. “We believe we invested at the bottom of the cycle. All things being equal, if the government rolls out what it plans to, in terms of infrastructure such as clinics, hospitals, police stations and schools, then Kwastina’s ideally placed to make those projects more cost-effective and efficient.

It will give us an advantage in the market not just in terms of technology, but also in terms of quality and consistency, which are critical for specifications involving tight tolerances,” says Booth.

Corobr ik is already hard at work extending its product range, with a number of new products being introduced. Current trials are being carried out with brick glazing for bespoke projects, as well as the raw clay material to produce different colours and g ive Kwastina a unique footprint in the country.

Booth says the commissioning process went smoothly and ascribes the success of the project to detailed planning and the fact that tried-and-tested technology was used, mainly imported from German suppliers.

PRECAST | ISSUE TWO | 2022

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| FEATURE |

MOVING TOWARDS SUSTAINABILITY Agreements and targets that will affect SA’s paint and coating industry

By Nicholas McDiarmid, editor: Precast Around the world and across industries, companies are working to make their operations greener and in line with international sustainability goals. The private sector, the scientific community and regulatory bodies and governments are all framing these goals around a number of international agreements, policy initiatives and sustainability targets. Here are some of the most important agreements that could affect the chemical and, in turn, coating industries.

South African companies have not been subject to the regulatory and trade agreements that compel their European, American and Australian counterparts to achieve meaningful emission reduction targets. Despite this, our private sector seems to be realising that sustainability is a business case, with legs for any company anticipating some level of longevity and success. On the public-sector front, the SA government has committed to significantly higher emission reduction targets set for emerging economies in the Paris Agreement and the UN’s Sustainable Development Goals. It has also announced that sustainability will be integrated into all public-sector procurement platforms, including tenders at local, provincial and national levels of government.

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A brief tour of existing sustainability initiatives The need to go green has become a working principle for most South Africans, so steps taken to regulate and formalise sustainability acrross all industrial and business operations must be inclusive, with industry, civil, corporate and societal input within a transparent national process.

European Union joining the agreement.

According to the UN, long-term goals of the agreement include: a reduction of global greenhouse gas emissions to limit the global temperature increase in the 21st century by 2°C, while working to increase that reduction by another 1,5°C, five-year reviews of signatory countries’ commitments and an agreement to provide developing countries with financing to help “mitigate climate change, strengthen resilience and enhance abilities to adapt to climate impacts”.

• Paris Agreement A legally binding international treaty, the Paris Agreement was reached at the UN Climate Change Conference (COP21) in Paris on 12 December 2015.

It was implemented on 4 November 2016, with 192 countries plus the

• Renewable Carbon Initiative Founded in 2020, the Renewable Carbon Initiative (RCI) is an interest group of more than 30 companies from the field of the chemical and material value chains. It was established to collaboratively enable the chemical and material

PRECAST | ISSUE TWO | 2022

(Above): The broad framework of sustainability encompasses business, social, personal and behavioural standards as guiding principles.

industries to tackle the challenges in meeting the climate goals set by the European Union and the sustainability expectations held by societies around

(Above): Establishing construction sites to ensure optimal use of materials should encourage recycling with well-placed receptacles and partnerships for utilisation.

| FEATURE |

(Right): Precast concrete structures have a massive potential to reduce the overall carbon output of the construction industry globally.

the globe. The overarching goal of the RCI is for fossil carbon extracted from below the ground to be completely substituted by renewable carbon, which is carbon from all alternative sources above the ground: biomass, CO2 and recycling. The RCI has developed 11 concrete policy recommendations on renewable carbon, carbon management, support for the transformation of the existing chemical infrastructure and the transformation of biofuel plants into chemical suppliers.

• Science-Based Targets initiative (SBTi) A partnership between CDP, the UN Global Compact, the World Resources Institute and the World Wide Fund for Nature, the SBTi is working to show companies how to reduce their greenhouse gas emissions quickly. Aiming to mobilise the private sector to lead on climate action, the initiative “defines and promotes best practice in emission reductions and net-zero targets in line with climate science”. It also provides technical assistance and expert resources to companies and assembles a team of experts to provide companies with independent assessments and validation of targets. The initiative partners with the Business Ambition for 1,5°C campaign, which aims to mobilise com-

panies to set net-zero, science-based targets to halt the global temperature rise to 1,5°C. • Sustainable Development Goals (SDGs) Set up by the UN General Assembly in 2015, the SDGs are 17 global goals designed to help organisations set targets and indicators around their sustainability initiatives. The 17 goals are: no poverty; zero hunger; good health and well-being; quality education; gender equality; clean water and sanitation; affordable energy; decent work and economic growth; industry innovation and infrastructure; reduced inequalities; sustainable cities and communities; responsible consumption and production; climate action; life below water; life on land; peace, justice and strong institutions; and partnerships for the goals.

(Below): Innovations in concrete design are critical to a sustainable future, such as the microcement used in this staircase.

Ten Principles Businesses are using the Ten Principles of the UN Global Compact to create policies, procedures and strategies that help them meet their responsibilities regarding people and the planet. The Ten Principles are based on human rights, labour, environment and anti-corruption. They are outlined on the UN’s website as follows: Human rights • Principle 1: Businesses should support and respect the protection of internationally proclaimed human rights.

• Principle 2: Ensure they are not complicit in human rights abuses.

Labour • Principle 3: Businesses should uphold freedom of association and the effective recognition of the right to collective bargaining.

• Principle 4: The elimination of all forms of forced and compulsory labour.

• Principle 5: The effective abolition of child labour.

• Principle 6: The elimination of discrimination in respect of employment and occupation.

Environment • Principle 7: Businesses should support a precautionary approach to environmental challenges.

• Principle 8: Undertake initiatives to pr omot e g r e a t e r e nv i r on me nt a l responsibility.

• Principle 9: Encourage the development and d if fusion of env ironmenta l ly friendly technologies.

Anti-corruption • Principle 10: Businesses should work against corruption in all its forms, including extortion and bribery.

PRECAST | ISSUE TWO | 2022

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| FEATURE |

(Above): Coatings for high moisture conditions tend to be environmentally friendly and easy to apply.

THE NATURE AND OUTLOOK OF THE SA PAINT AND COATING INDUSTRY

By Nicholas McDiarmid, editor: Precast The SA paint and coating market size is forecast to reach $2,1 billion by 2026, after growing at a compound annual growth rate of 5,6% during the forecast 2021-2026. With the rise in the building and construction sector, the consumption of paints and coatings is increasing and the local paint and coating market is witnessing an increase in demand. Paint and coating manufacturers are enhancing their formulations owing to innovative and more sustainable solutions. Also, the highly demanding paint and coating formulations used for architectural or industrial coatings have raised the market for the South African market.

Environmental issues and regulations associated with paints and coatings can create hurdles for the industry. For this reason, SA’s own industry has continued

to implement production methods in order to comply with environmental and other legislation, including a recent effort to reduce lead content in paint.

SA PAINTS AND COATINGS: A MARKET SEGMENT ANALYSIS

(Above): Water-based products such as epoxy resins offer a wide range of applications and are environmentally safe.

By formulations The waterborne segment held the largest share in the SA paint and coating market in 2020 and is expected to grow at a compound annual growth rate of 6,6% during the forecast period. The waterborne coating generally uses water as a solvent to disperse the resin which is added to create the coating. Its composition varies and may include as much as 80% water, with small amounts of other solvents such as glycol ethers. High water content makes waterborne coatings both environment-friendly and easy to apply.

PRECAST | ISSUE TWO | 2022

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| FEATURE |

(Right and below): Water-based products such as epoxy resins offer a wide range of applications and are environmentally safe.

Waterborne coatings offer a wide range of applications, including automotive, concrete, furniture, plastic and wood, and are compatible with both conventional and electrostatic application equipment.

Containers and paint guns used during the application of waterborne coatings can be easily cleaned with water or water-based cleaners, without the need for cleaners such as acetone, methyl acetate or paint thinners.

By resin The acr yl ic seg ment dominated t he market for SA paints and coatings in 2020 and is expected to grow at a compound annual growth rate of 5,1% during the forecast period. Acrylic surface coatings are used in various paint and coating market categories, including architectural, protective, decorative and others.

Acrylic surfaces act as a physical barrier layer to isolate the surface of metal from corrosive environments. Moreover, acrylic surface coatings are preferred for their inertness, industrial and colour retention properties when exposed to outdoor conditions. Waterborne acrylic resins are used in a wide range of industrial preservation and commercial architectural coatings. Acrylics have excellent resistance to U V light, toughness, resistance to grain cracking over wood and are also hydrolytically stable. For these reasons, the demand for them in paint and coatings has grown.

“The public sector is forecast to invest R109 billion on infrastructure between 2022 and 2024. This is largely due to higher planned investment by state-owned enterprises, which are expected to restart or launch infrastructure projects that were previously postponed.”

By application The decorative/architectural segment has been the primary market for the SA paint and coating market since 2020 and is expected to grow at a compound annual growth rate of 5,6% during the forecast period.

Decorative/Architectural is the major application of paints and coatings, which accounts for the major share in the local

market in terms of both value and volume.

Nowadays coatings with lower volatile organic compounds are no longer specialty product offerings, but must-have options.

Decorative/Architectural paints and coatings are used in roofs, floors, walls, façades, wooden trims, doors and other applications.

However, rising instalment projects of roofing technology in South African cities are anticipated to drive the demand for paints and coatings in the forecast period.

For instance, as part of the Cool Roofs and Insulation Partnership, the SA National Energy Development Institute began its ongoing initiative to install 26 000m² of cool roofing technology in the City of Cape Town in 2021.

SA’s market-drivers In SA, 75,1% of the medium-term estimate is spent on economic infrastructure, primarily by state-owned enterprises.

These funds will be used to increase power generation capability, strengthen sanitation and water systems, and upgrade and extend the transportation network.

The infrastructure for social care accounts

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PRECAST | ISSUE TWO | 2022

| FEATURE |

for 20,9% of the total, with health and education accounting for 4,6% and 7,2% respectively.

The public sector is forecast to invest R109 billion on infrastructure between 2022 and 2024. This is largely due to higher planned investment by stateowned enterprises, which are expected to restart or launch infrastructure projects that were previously postponed.

F luct uat ions i n pr ices of raw material can impact growth The prices of paints depend largely on the cost of raw materials. About 30% of the raw materials of paints and coatings are petroleum-based derivatives. Thus, any rise in the price of crude oil leads to a shift in the price of raw materials.

Over the past few years, there have been many increases in crude oil prices that have impacted the margins of paint firms.

Pressure rose further as a result of the recession and, thereafter, the fall in

demand. The main raw materials are titanium dioxide, phthalic anhydride and canarithrithol. They reflect about 50% of the overall cost. Thus, any fluctuation in petrol prices can impact market growth for SA paints and coatings.

Market landscape Technology launches, acquisitions and research and development activities are key strategies adopted by players in the local market.

Major players in the local market are the Sherwin Williams Company, PPG Industries Inc, AkzoNobel NV, Axalta Coating Systems, the Kansai Paint Co Ltd (Kansai Plascon Africa Ltd), Ferro SA, the Dekro Paints Group, Medal Paints, Africa Paints and Duram, among others.

(Below): The value of innovation in the coatings segment comes from its potential to extend the design life of structures and thus reduce their intrinsic carbon footprint.

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| FEATURE |

PLANNING THE NEXT STEP FOR

YOUR PRECAST BUSINESS Recognising signs and opportunities for precast plant growth and advice on how to get started.

By Claude Goguen, PE, LEED AP The precast concrete industry is continually advancing. Technologies in both manufacturing and mix designs are helping producers manufacture higher-quality products while enhancing production efficiency.

The construction industry’s use of precast is also expanding, creating a greater demand for new products.

Coupled w it h t he publ ic sector's increased demand for precast products in much of the works featured in its recovery plans, it might be appropriate to ask: “Is it time to grow?”

Identify the growing pains If you have not yet asked that question, here are the some of the signs that may signal it is time: • Cannot take on new work: Not every occurrence of turning down work requires contemplation of growth.

However, when it happens at an in-

creasing rate, it may be time to consider expansion. Clients and customers who find themselves repeatedly denied by a producer may seek an alternative source.

• Cannot meet current obligations due to production limitations: It is difficult to tell a customer that their product will not be delivered on time. Whatever the cause, there comes a time when a producer must examine ways to minimise impact.

• L a ck of roo m i n t h e pl a nt t o ge t everything done: The day’s production cycle can involve an innovative choreography of formwork, supplies and products in the plant. Insufficient space in the plant can lead to inefficiencies in production, quality issues and even safety risks for employees.

• Stress in the plant due to waiting for concrete or other materials: This may be a sign of too many mouths to feed with a batch plant that can only generate so much concrete in so much time.

(Above): The right adjustments at the right time can result in serious growth to precast manufacturing plants of all sizes.

| FEATURE |

• A m pl e o v e r t i m e : T i r e d employe e s may make more mistakes, risk ing quality issues or even injury. Equipment used for long hours will require more maintenance.

How to grow Growing a company may conjure up visions of acquiring more land, moving to a larger location, adding more manufacturing space, hiring more employees and buying more equipment. The good news is that expanding production capacity does not always require all of these actions. Instead, growing may mean examining the process, identifying inefficiencies and making changes within existing conditions. Adding personnel and/or implementing a change in employee responsibilities may seem small but can have a big impact.

A s su m i ng it ’s t i me to con s ider operational growth, owners should first

“Assuming it is time to consider operational growth, owners should first consider what they want their companies to become.”

consider what they want their companies to become. It is important to establish and confirm a goal and finish line, then work towards it. Some may want to specialise in a specif ic f ield, such as wastewater treatment, retaining walls or architectural products. Others may opt to manufacture a variety of new product lines. Envisaging the destination will make it easier to plot the journey.

Expanding the market Expanding the market can mean enhancing visibility. Precast plants can sometimes operate in obscurity.

Owners often depend solely on word-ofmouth and have little or no online presence.

While this may work now, it can change suddenly as old accounts are closed, contacts retired and the owner is not equipped to replenish the lost income. Those considering growing their operations should closely examine their online presence.

Technolog y has changed the way manufacturers produce precast. It has also changed the way customers buy and interact with suppliers. Creating and maintaining a robust online presence is key to supporting growth efforts.

Enhancing visibility also can apply to plant appearance. Precast plants are not like car dealerships. Rarely are plants and their products highly visible from a main

(Above): A better understanding of workers’ skills and interests can lead to adjustments that positively impact the plant as a whole.

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PRECAST | ISSUE TWO | 2022

(Above): Building your online presence is vital in today’s construction market.

road, with pristine landscaping surrounding ornate buildings.

These measures are not necessary, but producers should consider renovating the entrance and signage. Doing so can help expand visibility to potential customers and attract a high-quality workforce.

Talking to customers When considering growth, it is imperative to fully understand current and potential customers’ needs and challenges. Start by engaging with existing customers. Listen and observe how they unload, store and install precast products. Talking to them is the best way of identifying any potential modifications to existing structures and the need for new products. There may also be opportunities to diversify your product lines. Many ideas for new products originate with customer requests.

A unique project may be appealing and could generate an impressive addition to your list of projects. However, it is important to conduct a thorough assessment of future needs for any product beyond a one-time use. Will the cost of the equipment and materials justify further production?

A thorough review of the market may reveal a need for specific products. This may also turn into an opportunity for diversification. When diversifying into a new product line, first determine whether other businesses in the market already supply the product. Are these businesses successful at making the product? If so, determine whether your operation has the competence and ability to compete with the other suppliers before deciding to diversify.

| FEATURE |

(Above): Growth is relative and so is space.

Sometimes the biggest plants may need to boost efficiency more than their modest counterparts.

Assessing your workforce Like many organisations, you likely have a core group of valuable employees without whom the business could not operate. This core group will be invaluable during growth periods and must be nurtured. You may also f ind implementing lean production processes effective as you assess your workforce.

Once a thorough analysis is conducted, identify any new roles the plant needs to be filled.

Assessing your equipment and materials Growth does not always mean buying additional equipment. Smaller changes also could pay huge dividends. Adding a curing system could expedite product stripping and turning over forms.

Maybe using self-consolidating concrete could eliminate the consolidation stage.

If you plan to buy used equipment, ensure you have resources available for servicing. Some used equipment may come from manufacturers that are no longer in business.

Expanding the production facility If you are considering an expansion of your production facility, first consider whether the expansion and potential

future expansions can fit on the current piece of land. If not, can additional adjoining land be acquired?

Depending on your situation, it may be time to consider looking at another site or moving your entire operation.

Many other considerations should be taken into account when expanding a current property or moving to a new one.

Small steps lead to big rewards It is easy for precast plant owners and managers to find themselves on the proverbial hamster wheel day in and day out. When focused on keeping up with current production, it can be challenging to stop and consider adding more production capability.

However as the precast industry continues to grow, it is important not to be left behind. Remember that growth can be accomplished in small steps. Adding a product line, training employees and upgrading equipment can all lead to successful growth for your business.

About the author: Claude Goguen, PE, LEED AP, is NPCA’s director of technical education and outreach.

This article was adapted by Nicholas McDiarmid ( for Precast Magazine Issue 2 2022 from the article “Taking Your Precast Company to the Next Level” which first appeared in the National Precast Concrete Association’s (USA) Precast Inc. Magazine, 2021 – Quarter 4.

| GLOBAL VIEW |

Wrocław, Os. Plac Grunwaldzki. ©Zupagrafika

LIFE STORIES TOLD IN A CONCRETE VOICE The Tenants: Concrete Portraits of the Former Eastern Bloc (Supagrafika) excavates the secret truths of those living between hard, pitiless walls Mass housing in post-war socialist countries was a quick and effective way to provide homes for the expanding city populations after WWII, but after the collapse of the Soviet bloc, the fate of these constructions became uncertain. W hile modernist estates are being renovated or prematurely demolished, their tenants remain undaunted.

They have lived through the buildings’ golden years and darker times.

For the past decade, Zupagraf ika – publisher and author of unique books

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on modernist and brutalist architecture, design and photography – has documented the housing estates erected in central and Eastern Europe, still perceived by many as eyesores, through photographs and illustrated paper models. The Tenants features over 40 housing projects in 37 different cities of the former Eastern bloc and Yugoslavia. From Germany to Russia, all the way through Ukraine to Estonia, the album portrays the inhabitants of those complexes holding models of their homes, while sharing the stories of lives lived in prefab panel blocks.

The book includes a foreword by sociologist and urban researcher Maciej Frąckowiak and an index of the featured housing estates, providing an insight into their history. The portraits were taken by David Navarro and Martyna Sobecka, with contributions by local photographers.

The featured cities are Almaty, Belgrade, Berlin, Budapest, Chișinău, Dresden,

(Above): “I’ve lived here for 30 years. I used to work in a factory that produced those panels. Turns out that I built a house for myself.” – Tatjana (Pļavnieki, Riga).

(Left): The book is shipped worldwide and may be ordered from: www.zupagrafika.com/the-tenants.

Gdańsk, Halle-Neustadt, Kaliningrad, Katowice, Kraków, Kyiv, Ljubljana, Lviv, Łódź, Międzyrzecz, Minsk, Moscow, Norilsk, Omsk, Podgorica, Poznań, Prague, Riga, Rostock, St Petersburg, Skopje, Sofia, Szczecin, Tallinn, Tbilisi, Vilnius, Vorkuta, Warsaw, Wrocław, Yakutsk and Żyrardów.

IM/02/2021

YOUR PRECAST CONCRETE SPECIALIST PRODUCTS Storm Water Electrical Markers Water Reticulation Outdoor & Building Polymer Products Mining Solutions Kerb Inlet & Road Products Custom Products SERVICES Moulds Drawings

It’s always the last piece in a puzzle that goes missing!

That’s ‘cause we’ve got it!

TWINSTAR PRECAST solves those difficult, one-off jobs that make civil engineering & construction challenging.

Address: Unit 21, Hunky Dory Business Park, 9 Goedehoop Avenue (M57), Olifantsfontein

Telephone: (012) 670 9083

E-mail: info@twinstar.co.za

FROM THE PUBLISHERS OF PRECAST MAGAZINE

COMING IN YOUR

JUNE ISSUE Windows and doors Occupational health and safety: Injuries Specialised products and services: Renovations and restorations: Focus on wood and steel Maintenance and repair round-up Earth-moving equipment Trucks and bakkies

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For all brand marketing and advertising, contact: Ruwayda Mahomed on tel: (011) 883 4627 or jenny@isikhova.co.za