Quality where it counts

Avi Bhoora

Executive: Construction Materials | AfriSam

QUALITY

where it counts

Construction works in progress on the N1 during the Gauteng Freeway Improvement Project

Providing multifaceted solutions for SMMEs and top-tier contractors, AfriSam’s 2021 roads market expansion strategy has a dual urban and rural focus. IMIESA speaks to Avi Bhoora, executive: Construction Materials, AfriSam, about the significance of quality materials.

The roads market is expected to grow in 2021. How is AfriSam responding to opportunities?

AB With the current market for construction materials down to about a third of what it was at the peak of roadbuilding around 2012, the sector is certainly hoping for improvement in 2021. AfriSam is well placed to serve the market on the upswing, with more capacity that can be brought on stream as and when necessary.

With the impact of Covid-19, we expect spatial development will move out from the cities, as will road development. In response to these opportunities, our strategy includes gearing up for more rural work, in addition to our traditional focus on urban centres. This means becoming more flexible and mobile in our operations, such as converting equipment to a modular format that can be readily moved to and operated from outlying areas. For roadbuilders who are concerned about their carbon footprint, it is important to have a commercial supply of construction material as close to the road project as possible, reducing emissions from trucking. The challenge here, of unlicensed operators of ‘borrow pits’, will always remain.

What products are offered for cement stabilisation?

Road contractors look to AfriSam for solutions to two important aspects of achieving a quality road – modification and stabilisation. When contractors must deal with lower-quality material on-site – with high clay content and plasticity index – this generally needs to be modified with the use of lime. Higher-quality materials – those ‘bluer’ materials from the underlying rock layers rather than from the overburden – may require additional strengthening through stabilisation. Our Roadstab cement is a popular product in this regard, with its 32.5 classification in terms of SANS 50917-1. Manufactured at our Dudfield and Ulco factories, it is available both in bulk and in bags.

Why are quality aggregates so important for long-term durability?

Key to successful roadbuilding is the creation of a sub-base, base and wearing

course that can withstand considerable load pressures from traffic, especially with large trucks causing increased dynamic loading on the road these days. Good aggregates are vital for constructing both a solid foundation and a resilient crust. The final layer must resist wearing from the wheels and provide a safe friction coefficient, especially in wet conditions. It must also withstand ultraviolet and infrared rays so that it ameliorates against deterioration over time.

Different types of rock, such as dolerite and quartzite, are crushed to create aggregate and each has its own qualities to contribute. The mix design must carefully match these qualities to the requirements of the application.

Among the important tests conducted to ensure road strength and durability are the California bearing ratio, shrinkage from wet/dry cycles, and the aggregate crushing value. This all goes towards achieving an end result that will resist the ingress of water, which will wash out fines and quickly undermine the road’s integrity.

Does AfriSam have a strategy for the low-volume roads market?

Low-volume roads, which are usually undertaken by provincial and municipal authorities, have an important role in our economy. Often located in rural areas where there may not be much vehicular traffic, they give people easier access to markets and facilities.

AfriSam’s traditional focus is at the high end of the construction materials market – for instance, the G1 and G2 material for big roads linking cities and towns where economies of scale promote critical mass. We also have capacity, however, to link up with contractors on a broad range of project types, to set up the necessary facilities to supply material where volumes allow for cost absorption.

How can AfriSam assist in terms of SMME contractor development?

AfriSam has been involved for many years in new business development training, providing incubator programmes for people wanting to start small businesses. We also support small contractors through our Technical Department in their use of our products, as well as through our Centre of Product Excellence. This helps SMME contractors with skills, such as calculating their bills of quantities, or determining the

necessary quality of materials they should be using. There are also financial solutions that we offer to smaller businesses to help them deal with their limited liquidity. We also expect the SMMEs to play their part in terms of this collaboration, bringing their initiative, experience, responsibility and basic expertise.

Just-in-time delivery is key. What sets AfriSam apart from the competition?

Our experience has shown that just-in-time delivery for customers is crucial to their productivity and optimal usage of plant and equipment. Road contractors want to be able to do their flattening of material – following by mixing and compaction – without having to deal with rehandling material. They often cannot give us much lead time and could request 2 000 to 3 000 tonnes of material a day. Failure by suppliers to deliver quickly can lead to contractors having to pay costly penalties for not meeting deadlines, and also means that expensive equipment on-site can stand idle.

To avoid this, we work with a project programme to ensure that we generate enough product in advance and have stock available for when the customer needs it. On the aggregate delivery side, we have a system that plans a day in advance – scheduling loads by capacity of truck. By close of business each day, every truck is allocated a schedule for the following day. For our readymix deliveries, we employ technologically advanced planning and tracking systems that ensure trucks arrive on-site within 15 minutes of their scheduled times. This does depend largely on customers’ cooperation to achieve planned cycle times.

AfriSam supplied almost 9 000 m3 of readymix concrete to the Watt Street Interchange in Wynberg near Sandton

Please expand on current supply projects.

Recent road projects in Gauteng include the Watt Street Interchange in Wynberg near Sandton, where we provided almost 9 000 m3 of readymix for concrete works and conducted two large pours of over 550 m3 each. We have also supplied a road-widening project in the Marlboro area.

In KwaZulu-Natal, there has been much activity, including a bridge upgrade in the bus rapid transit project at Inanda Road and interchange upgrades in Westville, Richmond Road and Camperdown.

We are looking forward to the release of large road upgrade projects on the N2 and N3 highways, which could total up to R40 billion in value, with an expected nine packages to be released by the road authority. So far, we have been awarded the contract to supply construction material to the road upgrade from Lynnfield Park to Dardanelles, south of Pietermaritzburg.

What is AfriSam’s policy on quality assurance?

In terms of our aggregate quarries, there are various elements of AfriSam’s quality assurance and quality control imperative. As part of our quality assurance programme, we annually conduct a battery of tests at various frequencies to confirm the quality of our short-term reserves. We then follow up with process control and final product quality tests to ensure compliance to specification. As a member of the Aggregate and Sand Producers Association of Southern Africa (ASPASA), all our operations are audited for health, safety, environmental and other processes. Along with this accreditation, we have also won numerous ASPASA awards for our high levels of quality performance.

In addition, we are probably the only construction materials supplier with ISO 90012015 accreditation, auditing all our operations every second year, while our management and centralised support functions are audited every year. The SABS is the authentication body that conducts our audits.

The laboratory at our Centre of Product Excellence is one of the few that is accredited by the South African National Accreditation System. The final assurance is that we do carry product liability insurance.

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