Construction World February 2018

Safety milestone at Loeriesfontein.

Concrete Batch Plant and wash bay facilities.

Quality and cost The quality of the project’s core product – concrete – was proven and maintained throughout. In addition to the research and develop- ment invested in innovative (see section on Construction Innovation Technology) and environmentally friendly (see section on Environ- ment) concrete mixes, Concor Infrastructure’s testing is up to three to four times more thorough than conventional concrete inspections. They also exceed those undertaken on concrete performance on wind construction projects, and involve studying the micro-crystal formations of the concrete using Environmental Scanning Electronic Microscopes (ESEM). ESEM provides a clear understanding of the crystal formations between the geo-polymer and hydration technology used in the mixes. This is essential considering that these elements need to interweave correctly to ensure durability and strength of the concrete. As with all projects, time was of the essence and the construction of each foundation base – conducted on a continuous basis – took just 10 days from excavation to completion. When the foundations were all completed in December 2016, it was two months ahead of schedule. In terms of cost effectiveness, Concor Infrastructure’s work over the years also proves that the use geo-polymers –instead of

commercially sourced activators – can be cost effective. How risk was managed

Consistent workability and high performance of large volumes of concrete was required to avoid the risk of any delays or operational complications. Concor Infrastructure’s expertise in the complex inter-reactions that take place in geo-polymer concrete allowed a repetitive production rate, consistent workability of construction materials, and minimum standard deviation strength of the concrete. Critical testing of the performance of the wind farms’ concrete bases – which are under high fatigue – also enhanced risk management. Over-and-above the standard strength tests undertaken at 28 days, cube tests were done at 56 and 90 days to provide a longer term understanding of the strength and durability characteristics of the concrete. Concor Infrastructure’s concrete mixes achieve natural chemical inter-reactions, and have found synergies at ambient temperatures and much lower, such as those at Loeriesfontein Wind Farm and Khobab Wind Farm. Concor Infrastructure, previously known as Murray & Roberts Infrastructure, is part of Concor Construction which was recently acquired by a consortium led by Southern Palace Group. 

Project information • Client: South Africa Mainstream Renewable Power • Start date: 7 April 2015 • End date: 7 December 2017 • Project team: Concor Infrastructure • Principal agent: Mainstream Renewable Power • Project manager: Mainstream Renewable Power • Consulting engineer: WorleyParsons

Internal access Road 1 on Loeriesfontein Wind Farm.

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CONSTRUCTION WORLD FEBRUARY 2018