Concrete Repair Solution for Concrete Bridges Suffering from Effects of Carbonation
Background
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.
The Solution
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.
Project Profile - Canal Bridges Northwich