The Cyclo-Pedestrian Footbridge Over the Former L160 Railway Line in Brussels

The cyclo-pedestrian footbridge built at the beginning of 2009 over the former L160 railway line in Brussels (Auderghem) consists of a 58-metre long reinforced concrete slab (cross-section 4.50m x 0.30m), “chaotically” supported by 37 wooden stilts (Douglas Fir). Its horizontal stability is ensured by two concrete abutments; the stilts, ball-and-socket jointed at each end, take up the vertical loads only. The objective was to produce durable concrete, and therefore to verify its behaviour in times of frost, as well as the corrosion of the reinforcements which, in our part of the world (Belgium), are the main factors behind the degradation of reinforced concrete structures, the corrosion of the reinforcements being induced mainly by the carbonation of the concrete and the penetration of the chloride ions resulting from de-icing salt. This durability objective was of paramount importance. Indeed, the pathway concrete slab, in a single operation, all functions: it is structure, coating and facing at one and the same time. This project was undertaken, not only by R&D engineers, but also by concrete practitioners.