Client: Wessex Water
Main contractor: SWCR Ltd
Work involved: Remedial Works to STW
Date: February 2008
Numerous defects to the filter bed walls were identified by Wessex Water; they included spalling concrete with reinforcement bars showing, cracks running up the walls, expansion joints to walls failing and failing concrete under steel plates fitted for the sprinklers to run on.
High pressure power washing was used to remove surface contaminants and clean the surfaces to help with identifying any hidden defects. Redundant steel plates were removed and traditional concrete repairs to the defective areas under the plates and spalled concrete areas.
Sealant to expansion joints ripped out and edges made good and prepared followed by the installation of new polysulphide sealant.
Cracks were repaired by opening up the cracks and cutting horizontal slots across the cracks (crack stitching). Fitting new reinforcement steel to the slots embedded in epoxy resin and traditional concrete repair to finish.