Concrete Repair Solution for Concrete Bridges Suffering from Effects of Carbonation
On five of the road bridges above the Shropshire Union Canal (Snapes, Pickerings, Wardle, Henhull & Cheney road bridges), inadequate concrete cover to the steel reinforcement had given rise to premature failure from the effects of carbonation.
Following consultation with specialist contractor Gables UK Limited, a complete Flexcrete concrete repair system comprising of repair mortars, a fairing coat and a cementitious coating were specified in order to repair the existing damage and protect the concrete from future degradation. Initial cleaning was carried out using a high pressure water lance before localised repairs either with Monomix – a high strength shrinkage compensated mortar – or with Fastfill – a rapid curing mortar which sets in as little as 10 minutes. General concrete surfaces were bag rubbed with Monolevel 844SP in order to provide a fair-faced waterproof finish. Cemprotec E942 was selected as the final protective coating, a 2mm thick epoxy and polymer modified formulation, which provides equivalent effective cover to approximately 80cm of typical concrete.