Construction World June 2015

PROJECT PROFILE

Project highlights In its building material supply performance for the construction of Metolong Dam, Lafarge South Africa has clearly demonstrated the meaning of the Lafarge Group’s brand signature Building better cities . The company’s ‘One Lafarge’ true partnership approach with the main contractor has technically, commercially and logistically contributed innovative solutions to help the construction of a project rather than merely being a commodity building material supplier. The project will uplift a key economic area around the capital city of Lesotho. The longer term impact is that Lafarge has achieved a significant technical breakthrough in the choice of cement for RCC dam construction in Southern Africa. Its innovative CEM II Powercrete Plus cement offers: • Strength performance on a par with traditional CEM I products. • Reduced heat of hydration. • Better workability. • Versatility on site through being able to be blended further with fly ash to meet project requirements for a cost-effective variety of mixes. • Better flowability of CVC mixes over long distances from a fixed on site batch plant. • Creates concrete with essentially the same matrix as with a CEM I cement but is denser, more durable and impermeable.

high quality product is not only a significant contributor to lower temperatures but the peak temperatures also occur at a later age. In addition to controlling heat of hydra- tion, incorporating DuraPozz ® produces highly effective mix designs that enhance the ultimate strength and durability properties of concrete, while also aiding construction with the improved workability and ‘flowa- bility’ of the mixes. Delivery capability Lafarge South Africa’s extensive production facility footprint (five fly ash plants and three cement plants), means that it is in the unique position of being able to guarantee supply of large quantities of consistent high quality cement and fly ash for major projects. In addition, the company’s logistics teams have a proud track record for ensuring product is always available on a customer’s project site no matter what delivery chal- lenges may be encountered. In complying with the contractor’s requirement of an eight day estimated usage stock on site, the project has not once run short of cement or fly ash. The excel- lent performance of the Lafarge produc- tion plants has meant that it has not been necessary to make use of any backup produc- tion facilities. The abnormal rainy season in early 2014 had a significant impact on the Metolong Dam construction programme, which has contributed to pushing back the anticipated completion time from the second quarter to the last quarter of 2014 (the contract time was also extended by the total amount of

concrete needing to be placed increasing from the estimates at the start of the contract). Delivering to the Metolong project site had its own challenges: in addition to coping with border crossing delays, the final 18 km section of dirt road was frequently flooded and damaged by the rains. Apart from this, the nature of dam construction leads to considerable vari- ance in building material usage – when the conditions were right, the contractor did major non-stop pours and the consump- tion of cementitious materials increased dramatically. The contractor is extremely complimentary about the success of Lafarge South Africa in overcoming these delivery challenges. Environment impact Ash Resources’ environmentally-friendly fly ash plays two important ‘green engineering’ roles. It is a key ingredient in Lafarge South Africa’s range of lower carbon footprint cement products, and it has a direct role on site for further extension of the Powercrete Plus cement: • Recycling a material that was originally considered a waste product of the Eskom coal-fired power stations, as a value-added cementitious building material. • Reducing process and energy input carbon dioxide (CO 2 ) emissions. Each ton of fly ash used in cement and concrete saves approximately 1 ton of CO 2 emissions and reduces dependence on non-renewable raw materials. (During the last 12 years, the use of Ash

Resources’ fly ash by the local cement, readymix and construction industries, has saved South Africa in excess of 17,5 million tons of greenhouse gas emissions). • Reducing the consumption of non- renewable natural resources. • Reducing the size of power station landfill sites. • Improving concrete durability, prolonging the life cycle of concrete structures. Health and safety Safety is a non-negotiable number one priority at Lafarge South Africa and includes contractors working on the company’s sites as well as transport contractors. Contractor drivers have embraced the Lafarge safety training, as well as the rigorous procedures for checking the road worthiness of road tankers before they are allowed to be filled at the supplying plant. Lafarge South Africa strives to create a partnership with transporters in the drive for excellence in safety performance. In this way, the company is viewed as a trusted advisor on safety procedures rather than being viewed as merely a commodity supplier. The drivers’ safe working behaviour also makes them an ambassador for the Lafarge brand. Ash Resources has supplied the Metolong Dam project for the last two years without a Lost-Time Injury at its Lethabo production plant or to its transport contractors. Simi- larly, Lafarge Lichtenburg Cement Works, in the North West Province, has supplied Powercrete Plus without a Lost Time Injury on the plant or to its transport contractors.

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CONSTRUCTION WORLD JUNE 2015