Langebrug Gorinchem
After an extensive inspection, which was carried out using a boat so that the concrete parts on the underside of the bridge were also accessible, the entire concrete structure was surveyed. Analysis revealed incipient ASR in the structure, which causes a gradual decrease of concrete cohesion.
Solid Services recommended that a watertight membrane be applied to the top of the bridge deck and a protective coating system be applied to all other concrete components. This will minimise moisture transport in the structure, preventing the progression of ASR.
Additional information
Alkali silica reaction (ASR) is a chemical reaction between alkalis in the concrete, water and reactive silica from the aggregate used in concrete. This reaction causes the formation of an expansive gel that crushes the concrete from the inside. Many cases of ASR damage in the Netherlands did not come to light until 1990-2000; almost all cases involve concrete viaduct structures.