Lafarge SA supplied a range of innovative cement solutions for the Metalong Dam project in Lesotho.
Lesotho’s capital, Maseru, has historically suffered from water shortages. There is now new hope for the people of the region thanks to the Metolong Dam and Water Supply Programme (MDWSP), which is set to improve water delivery to domestic users and the country’s textile industry, an important source of employment.
A major part of the new scheme is the Metolong Dam, which is being constructed on the Phuthiatsana River. The dam features 83m-high, roller-compacted concrete (RCC) walls with a design crest length of 280m. It is estimated that 330 000m³ of RCC and 40 000m³ of conventional vibrated concrete (CVC) will be needed to construct the Metolong Dam, which is why the Chinese main contractor, Sinohydro, established an on-site batch facility for the concrete.
Sinohydro is renowned in the construction and hydropower industry, and the group is involved in a range of projects on the African continent. One of the international projects that Sinohydro has worked on is the world’s largest dam, namely China’s Three Gorges Dam.
Lafarge South Africa was chosen as the supplier for this project for a number of reasons, including their technical experience as well as their ability to supply all of its requirements for cement and fly-ash. Lafarge recently introduced what is known as the “One Lafarge” approach to major infrastructure developments. The goal of this approach is to ensure that customers receive the optimum all-round benefits from the company’s resources. Working with Sinohydro was in line with this approach and it further reflected Lafarge’s policy of building long-term relationships by delivering true value.
In the past, CEM I products have been used for most water infrastructure projects. While many contractors and engineers are hesitant about changing tried and trusted building methods, Lafarge has phased out these cements and developed a complete range of innovative fly-ash extended products. The challenge that the company faced was to convince the project team of the merits of its CEM II product.
The merits of Lafarge’s innovative CEM II for water infrastructure projects
Lafarge proposed their premium technical cement, Powercrete Plus CEM II 42,5R, for the project, knowing that heat of hydration would be a concern. Powercrete Plus CEM II 42,5R is a low-heat cement and it also offers the benefit of being able to be extended with fly-ash on site. Sinohydro, along with the engineers working on the project, weren’t familiar with this versatile, high performance product of cement and Lafarge had to put in significant effort to showcase the technical benefits of the product.
Lafarge’s highly regarded accredited civil engineering testing facility, Quality Department Southern Africa (QDSA), conducted laboratory evaluations of the various concrete mixes and presented the results to the main contractor. QDSA recommended Powercrete Plus premium technical cement, and DuraPozz® classified siliceous fly-ash from Ash Resources’ Lethabo facility were used as binder material in both the RCC and the CVC mixes. The product exceeded the contractor’s expectations with regards to strength and performance.
Lafarge has an extensive production facility footprint (five fly-ash plants and three cement plants), putting the company in the unique position of being able to guarantee supply of large quantities of consistent high-quality cement and fly-ash for major projects.
“We are very pleased that we chose the right cement and fly-ash supplier in Lafarge. They not only lived up to their guarantees, but they also lived up to their reputation for acting as committed supply partners in a project. The company gave us outstanding support, achieving a 100% on-time delivery record to site. If we build other projects in Lesotho or South Africa, we would be happy to have Lafarge as our cement and fly-ash supplier,” commented Xie Yunhua, deputy project manager of Sinohydro.
Lafarge South Africa
Tel: 011 657 0000