Construction World March 2020

REHABILITATION OF THE M1 'DOUBLE DECKER' T he Johannesburg Roads Agency (JRS), in their commitment to provide

concrete structures, and to increase sheer load capacity, SikaWrap-300 C was used. The concrete surface area was treated with the Sikaguard-705 L silane water repellent and SikaTop Seal-107, a polymer PRGLͤHG FHPHQW ZDWHUSURRI DQG FKORULGH and Carbonation resistant, liquid applied membrane coating for concrete. To ensure that all product applications were executed correctly at every stage, all those involved in the project were provided with training and on site support by the Sika team. This included training in processes such as surface preparation, product mixing

quality roads that are accessible and safe, decided it was time for one of its major bridges to be rehabilitated. The M1 ‘double decker’ is a highway bridge in the city of Johannesburg, between Newton and Fordsburg, which was posing a safety threat to motorists. This R15-million rehabilitation project, with a bridge-span of 1,02 km, was no small task and required the expertise of many specialists. Khato Civils were appointed as the main contractor for the

project and assisted by 17 small, medium and micro enterprises. A phenomenal number of 164 people were employed on this rehabilitation process. Sika was Khato Civils’ brand of choice due to our reliable and long-lasting products. The bridge consists of two reinforced concrete deck superstructures, one directly above the other, that are supported RQ WUHVWOH OLNH SLHUV $ YDULHW\ RI 6LND SURGXFWV ZHUH VSHFLͤHG IRU structural repairs, structural strengthening and coatings. SikaTop Armatec-110 EpoCem was used as a rebar protective coating in the structural repairs, as it is highly effective for corrosion prevention in concrete reinforcing. Also used in the repair process were the user-friendly Sika Monotop-615 HB which is designed for thick layer concrete repairs, especially for overhead and vertical applications; as well as the SikaGrout-212. For structural strengthening of reinforced

and product application. A major challenge to all involved was that WKH PRWRUZD\ ZDV XQGHU GDLO\ XVH E\ WUDͦF $V GLVUXSWLRQ WR WUDͦF KDG WR UHPDLQ OLPLWHG LW ZDV DQWLFLSDWHG WKDW LW ZRXOG EH GLͦFXOW WR complete the task within the allotted 22-month time frame. However, with the use of superior, tailor-made products and the appointment of a committed contractor, the project was completed, three months ahead of time. Former Mayor Herman Mashaba, who had stated his main concern and priority was the safety of motorists, visited the site and was pleased with the progress. Roads and bridges form a critical part of the transport infrastructure, especially in a growing city, so their maintenance and rehabilitation are important. Now complete, the mayor and all his citizens of Johannesburg can rest assured that the best products have been used for the project and that this GRXEOH GHFNHU KDV D ͤUP IRXQGDWLRQ ƒ

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CONSTRUCTION WORLD MARCH 2020