Construction World May 2019

resistance compared to untreated concrete. The concrete wall was repaired using Sika MonoTop-610 an easy to apply cementitious, polymer-modified, one-component slurry. This high quality, anti- corrosion primer provides excellent bond for Sika MonoTop-612 a high strength repair mortar containing silica fume and synthetic fibre reinforcement. Providing excellent slump resistance, it is particularly suitable for application on overhead and vertical surfaces. Sika Waterbar Type O-20 was centrally placed in all the expansion joints. Manufactured from virgin thermoplastic PVC for strength and flexibility and easy, on-site welding. Internationally tested Sika- Waterbars are used to seal construction and expansion joints in all water retaining structures. They are designed to withstand high water pressure and are supplied in rolls of various widths and types Used as admixtures for the structural concrete and blinding concrete, Sika Plast Stallion-2 and Sika Plast V220 were used, as multi-purpose water reducers and superplasticizers, utilizing Sika's ViscoCrete polycarboxylate polymer technology. Its higher ultimate strengths allow for greater engineering design, flexibility and structural economies. Two main challenges faced during this project was the drilling of 21m into the ground and create a grout wall before starting with the actual wall as water kept rising when drilling into the ground. Drilling into the rock for the anchor rods was also another challenge due to the rock being so hard, which in turned caused the drill bit to break off or go blunt. Regardless of these challenges, the project was completed in the timeframe of 18 months. Corporate social investment Approximately 120 jobs were created throughout the development on the various project extensions, including construction of access

roads, testing & grouting of the foundation, construction of the spillway, concrete inlet tower Access Bridge, and installation of outlet pipes. The unskilled local labour that were brought in to assist with the Dam, were given basic training on site, covering various applications and products that were being used (Not just Sika applications) and was done by the Raubex Construction. Their contract lasted for the duration of the project. Environmental impact consideration Sika has local technology and resources to produce all products necessary for the applications awarded to us and therefore are proud that 95% of products supplied on site were locally produced. Sika products, tried and tested for their reliability and endurance, have been used in this project, adding to the sustainability value of Cornelis River Dam. The original dam was badly silted and had no capacity left for raw water storage. It also posed a risk element of contamination from a nearby kraal which necessitated the project. The concrete spillway was designed to safely accommodate the regional maximum flood without overtopping of the non-overspill crest when the dam is full as recommended. The surface area of the dam at full supply level is 98 hectare Health & Safety A Health & Safety audit was conducted both on the physical site as well as the administration of the project with the contractor scoring over 93%. A Health and Safety officer was present on site during all working hours. Any person entering site had to report to the site office before proceeding and always supervised on site. 

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CONSTRUCTION WORLD MAY 2019