Concrete Repair & Protection

Three fifteen storey tower blocks built in the 1960s using no-fines concrete and a brick outer skin.

Wall tie investigations revealed existing galvanised fishtail wall cramps and galvanised butterfly ties installed at inadequate densities.

The cantilevered concrete balconies showed evidence of deterioration, with visibly spalling concrete and exposed corroding reinforcement. Concrete investigation and sampling works found areas of low reinforcement cover and high carbonation depths and chloride levels.

Bersche-Rolt's in-house site personnel installed remedial resin / resin cavity wall ties in the no-fines inner leaf to bring the density up to the standards required for the installation of external wall insulation.

Repairs were also undertaken to damaged areas of concrete, along with the replacement of reinforcement, the application of a migrating corrosion inhibitor and sacrificial anodes.

All work was undertaken from mastclimbing work platforms with debris protection and exclusion zones set up around the base of each mast.