Quality readymix equals quality construction. In an economic climate where it is unthinkable to rebuild structures that have failed because the quality of the supplied concrete was not up to standard, the processes to ensure the quality of concrete is vital. Construction World spoke to Amit Dawneerangen, General Manager Readymix at AfriSam.
Why is quality so important when it comes to readymix?
There are a number of factors why quality readymix is important. For AfriSam, the safety factor is the most important. When concrete is supplied to a project and the structure fails, it has serious implications as you are dealing with people’s lives.
The second centres on reputation. As a supplier your reputation and credibility is intricately associated with a structure. If it needs to be demolished because of quality issues, it casts doubt on your ability to supply quality concrete for future projects.
The third reason centres on the long-term durability and sustainability of the structure. If the quality of the supplied concrete is not as per what was specified in the design, it could lead to unintended maintenance costs down the line.
Time (for the contractor) is another factor why the quality of supplied concrete is vital. Projects have tight deadlines and stoppages or disruptions due to the areas that must be repaired or replaced, cannot be afforded.
The last factor is cost. At the end of the day someone has to foot the bill for making good if the quality of the supplied concrete is not up to standard.
What processes are in place to ensure the quality of AfriSam’s readymix?
The mix design is what guarantees the quality of the concrete AfriSam supplies. Our batching plants have computerised batching systems to ensure that there is little human intervention needed to execute mix designs. All mix designs are stored onto a central system and downloaded to the batch plant.
Afrisam employs highly skilled people in its product technical department. These experienced concrete technologists are familiar with the performance of concrete and are responsible for designing and maintaining our product range . That instils confidence in the customers whom we supply.
The end product is dependent on using high quality materials – cement, aggregates, sand and admixtures. It is important not to opt for the cheapest input material as this compromises the quality of the end product.
How has AfriSam differentiated itself from competitors with regard to standards and quality?
AfriSam’s readymix business carries an ISO 9001 certification. From a standards perspective, this is what governs the way in which we run our business. We have policies and procedures in place and work instructions that every employee is familiar with and to which they work accordingly. By following that system, it gives us the confidence to know that we are able to produce quality concrete.
Another differentiator is AfriSam’s ability to create customised solutions. Our standard product portfolio of general concrete ranges in strength from 10 MPa up to 50 MPa. For specific projects we are able to design customised concrete mixes to meet the requirements for the application, e.g. High Strength concrete, self compacting concrete, concrete for road pavements, and durability concrete.
For a specific project a competitor may price normal products (not customised products), a contractor might accept that quote and only afterwards realise that those products do not meet the specifications of the project. That is where we find that many of our competitors do not have the capabilities to design these products and produce it to a consistent quality.
These designs take place regionally at the various product technical departments based in Gauteng, Cape Town and KwaZulu-Natal. We do call on AfriSam’s Centre of Product Excellence for durability testing as they are adequately set up for (especially) initial testing.
How have you managed to sustain the focus of quality in a difficult economic climate?
Contractors are under pressure to secure projects because of the limited number of projects out to tender. In order to secure work, prices are undercut which has implications down the line as this puts pressure on suppliers.
Even in these tough times, quality is something AfriSam will never compromise on. The cost of concrete is highly dependent on the cost of the input materials that are used. That is where AfriSam has had to be smart to ensure that we use quality input material, while at the same time negotiating with our suppliers to ensure we strike the right balance in terms of achieving what we want to versus the input costs.
We maintain quality by designing cost effective mixes that use materials at our disposal. We, for instance, use higher quantities of cementitious extenders and work with admixture suppliers to design admixture products that are effective at high extender levels. However, from a cement replacement level, the mix has to be designed adequately so that the correct early and late strengths are achieved.
How do you control costs and quality internally?
The operational efficiency is the engine room of any readymix business. With this in mind we aim to ensure that our batching accuracies are within the tolerances required as per the SANS readymix specification. Our internal specifications are tighter than the SANS specifications with the result that we weigh as close to the actual amount as possible as anything over this will be wastage.
Concrete is measured according to the 28 MPA day characteristic strength, which is stipulated by the structural design, and is designed to have a suitable strength margin. When a specific grade of concrete is ordered, AfriSam’s mix design ensures that the concrete will achieve the characteristic strength with an adequate strength margin in order to cater for the variability that comes from the input materials.
We test our concrete according to a fixed sampling frequency so as to ensure that we meet the requirements of the mix design. Overdesign is also wastage – that is where the quality department ensures that are our mix designs are suitably optimized to achieve the strength margin. This performance optimisation by strength monitoring is one of the main functions of the product technical department.
AfriSam carefully manages the cost of the input materials (cement, aggregate, admixtures and sand). Many suppliers make the mistake of choosing the cheapest materials based on rand per ton or rands per litre. That is wrong. You have to test whatever input material you are using in concrete to determine its performance. We rather measure it on a rand per cubic metre basis. We run a vigorous internal testing programme to make sure our input materials are optimised for both cost and performance.
How do you maximise AfriSam’s efficiencies?
As Afrisam is a vertically integrated business, readymix is an important part of the business. Depending on location, AfriSam readymix will use AfriSam aggregates from its quarries, AfriSam cement from its factories, and slagment from Vanderbijlpark.
We also maximise our delivery. We have a fleet of readymix trucks in each region and have the flexibility to move the fleet around in order to cater for areas where there is demand.
These readymix trucks play an important role in AfriSam’s brand as the branded trucks are highly visible. In that sense they are our leading brand ambassadors and make our payoff line of ‘Creating Concrete Possibilities’ visible to the public.
What underlies the high performance levels at AfriSam?
The culture at AfriSam is a differentiating factor. AfriSam’s focus of ‘people, planet and performance’ is directly linked to our values and part of our DNA.
AfriSam has an effective performance management system in place through the use of Key Performance Indicators (KPI’s). People know what needs to be done and how they are measured – and they perform according to that. That is one of the reasons for the high performance levels that we have been able to sustain during these challenging times.
Where are AfriSam’s readmix facilities located?
These facilities are currently in Gauteng, Mpumalanga, KwaZulu-Natal and the Western Cape. AfriSam readymix is situated in the metropolitan areas as this is where we see growth at the moment. However, our demand driven approach makes us flexible enough to erect plants in areas where we see increased demand.
How do you ensure a smooth ordering and delivery process?
Execution is vital. With readymix you are dealing with a live product which has a shelf life. There has to be close communication between the contact centre, scheduling department, batch plants, customers and transport control department. These legs are crucial in successfully executing the delivery on the day.
Do you provide technical and scientific information?
We have started a focused and targeted engagement with consulting engineers and contractors. We educate them in terms of the more intricate details related to concrete technology – especially on aspects such as curing, placing and finishing. You can have the best concrete mix design but what happens after it is placed determines how the concrete will perform. It helps us in minimising any defects that might manifest once the concrete has been supplied and placed. We have found the engagements useful in building relationships with contractors and engineers as we get to share the information we have acquired over the last 25 years.
