Construction World November 2017

ADMIXTURES

Products for two MAJOR HIGHWAY CONSTRUCTION projects

Construction Chemicals is supplying products for two major highway bridge construction projects in Gauteng: the new Bus Rapid Transport (BRT) cable stayed bridge over the M1 near Sandton, and for maintenance work on several N14 bridges between the Hartbeespoort/ Sandton and Lanseria off-ramps. a.b.e. is part of the Chryso Southern Africa Group.

forms part of the Department’s mission to improve road conditions in the major arterial routes and improve the surface and sub- surface drainage. The scope of works assigned to Power Construction includes the reconstruction of the road base and sub-base, milling out old asphalt in slow lanes and planing asphalt in fast lanes; construction of new concrete lined side drains as well as new subsoil drains; construction of new bridge parapets and the provision of new fence line and guardrails. a.b.e. is supplying products to Power Construction as well as the sub-contractor, DSC Zendon, which is handling the refurbishment of sealing joints and concrete repairs on the bridges. “silocoat is being block-brush applied by DSC Zendon to a total area of over 1 300 m 2 on the upstands of the bridges. silocoat is a two-part polymer modified cementitious coating that can easily be mixed on site and applied with brush, roller or spray gun. The product cures to form a waterproof elastomeric membrane and has been widely all over southern Africa and the Indian Ocean islands to waterproof new and old silos,” Pelser explains. Dow Corning 890-SL is a self-levelling joint sealant

Daniel Lambie, Technical Sales Consultant for a.b.e. in Boksburg, says for the first phase of the new Rea Vaya BRT cable stayed bridge construction, a.b.e. supplied the main contractor, WBHO Construction, with four products: duragrout; durarep FR;epidermix 395; and epidermix 345. “duragrout is a non-shrink, cement- based grouting compound, containing graded siliceous aggregates and chemical reagents that prevent shrinkage during curing. The product can be used for bedding applications such as on column base plates, machinery base plates, bearing plates and crane rails. It is ideal for grouting anchor bolts, cables, starter bars, and top steel; and also for repairing cavities in concrete,” Lambie states. The new 255 m long BRT cable stayed

bridge will include dedicated bus lanes as well as cycling lanes. The other a.b.e. products supplied to WBHO for this project are durarep FR, a fibre- reinforced cement-based structural repair mortar which is chloride-free and ready to use; epidermix 395, a liquid epoxy grouting compound; and epidermix 345, a solvent- free, wet-to-dry epoxy resin system with extended open time formulation. Rens Pelser, a.b.e. Technical Sales Consultant, says for the refurbishment of the N14 highway bridges, a.b.e. is supplying the main contractor, Power Construction, with three products: silocoat; Dow Corning 890-SL; and Dow Corning 888. The Gauteng Department of Roads and Transport is undertaking a multi-million rand project to rehabilitate the N14. The project

that requires no tools to apply. It can be extruded from well below freezing point to temperatures of around 50 degrees Celsius and can extend by 100% and compress by 50%. The sealant easily flows into irregular joint widths and, with a skin-over times of an hour or less, allows for roadways to be quickly opened to traffic. Dow Corning 888 silicone joint sealant offers much the same benefits as 890-SL and is ideal for the concrete bridge joints without any primer required for bonding, Pelser adds.  Work in progress on the N14 highway bridges for which a.b.e. Construction Chemicals is supplying three products.

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CONSTRUCTION WORLD NOVEMBER 2017