Desert bridges get extensive overhaul

based on a combination of epoxy resins and selected high-strength aggregates.

Swakopmund bridge deck

About 480 m² of bridge deck and approach slabs at the Swakopmund site had SikaBit Pro P40 PE applied. Reinforced with a dimensionally stable, non-woven polyester inlay, the underside has a thin polyethylene burn-off film for effortless application. It can be applied to wood, metal and concrete substrates, including over existing bitumen roofing membranes.

Located some 80 km apart, these comprise the Omaruru River Bridge in Henties Bay and the Swakopmund roadover-rail bridge, with refurbishment on both structures completed concurrently by Actual Impact Group. Specialist solutions for all phases were supplied by Sika.

Initial bridge repair work was attained with SikaGrout-212, an easy-to-use, singlecomponent, high-strength, shrinkagecompensated cementitious grout; and Sika MonoTop-412 NFG, an R4 class repair mortar with corrosion inhibitor. On both projects, Sikalastic-152 was also applied to all exposed concrete components, which totalled around 4 450 m2

Sikalastic-152 is a two-part, cementitious, polymer-modified, flexible, crack-bridging,

Index To Advertisers

fibre-reinforced mortar for waterproofing and concrete protection that can be applied to various types of construction substrates. In turn, the expansion joints on both bridges were sealed with the Sikadur-Combiflex SG system.

Both Sikadur-42 ZA and Sikadur-43 ZA were used under the bridge bearing pads on both sites. The former is a three-part, moisture-tolerant, multipurpose epoxy grouting system, and the latter a solvent-free, threecomponent, repair and filling mortar

On the general concrete work, Sika AnchorFix-2+, a solvent-free, twocomponent anchoring adhesive, was used to anchor the concrete balustrades on the bridges. In turn, Sika Antisol E was used as a concrete curing agent. The latter is a ready-to-use, spray-applied, liquid wax emulsion that prevents water loss from the surface of freshly placed concrete, without affecting the normal setting action.

With the works completed, the bridges are once again ready to withstand the harsh environmental elements on one of Namibia’s most important tourism and commercial corridors.

On the general concrete work, Sika AnchorFix-2+, a solvent-free, two-component anchoring adhesive, was used to anchor the concrete balustrades on the bridges