When it comes to quality, durability and sustainability are interlinked

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

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

Does the right cement make a difference?

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

How does AfriSam add value?

AD Working closely with contractors in the road construction space, we provide a turnkey package in terms of project-specific aggregate, cement and readymix solutions for road, bridge, and ancillary infrastructure such as culverts and pavements. On top of that, we’re able to produce customised products to meet the requirements of any project specification. Additionally, every AfriSam product is supported by our Centre for Product Excellence (CPE), which includes in-field technical support. Throughout, quality control is paramount.

So, it’s an exact science?

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

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

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

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

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

It’s not uncommon to see cement spread by hand ahead of in-situ mechanical stabilisation. However, a faster alternative is to use our specially designed cement-spreading truck services. Fitted with spreader bars, our drivers are trained to work with site managers to ensure an even application of cement during construction.

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

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

Are there any new road specifications to note?

The COTO draft specification document was issued for implementation in October 2020 and is meant to replace the COLTO document. Currently, most projects are still utilising COLTO and very few have implemented COTO as