Construction World August 2019

CEMENT & CONCRETE TECHNOLOGY

Reliable refurbishment systems FOR KOMATI RIVER BRIDGE

SMEC South Africa was appointed by Trans African Concessions (TRAC) to undertake the detailed inspection, rehabilitation design and construction supervision of the Komati River Bridge refurbishment project. The bridge is situated on the N4 Toll Route, Section 8 and is an important river crossing for freight travelling between South Africa and Mozambique.

by the locked bearings. March 2017 saw the start of the project where Sika’s specialised products were specified by DSC Zendon whom the client, TRAC appointed to complete the rehabilitation. Jaun-Roe van Wyk, Sales Consultant for Sika South Africa, recommended Sika’s most renowned products. Sikadur-52 ZA was used for crack injection. This was completed by drilling 6 mm holes into the cracks to a depth of 20 mm. The injection was by means of copper piping used to inject the epoxy into the crack which was bonded to the concrete with Sikadur-31 DW epoxy mortar. The crack was thereafter closed with Sikadur-31

D uring a scheduled inspection, a number of defects were identified. Defects included locked bearings, shear cracks and flexural cracks in the deck beams. The shear and flexural cracks were believed to have been related to thermal loading caused

DW and allowed to cure for 24 hours. Sikadur-30 was used in conjunction with the composite carbon fibre plates which were cut to the correct sizes as specified. All areas that had to be strengthened were inspected for

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CONSTRUCTION WORLD AUGUST 2019