THE PROBLEM
The new precast water storage reservoir was leaking and a solution was required to treat suspected areas of water egress.
SOLUTION
The precast panel joints required a flexible solution due to their post tensioned nature. For this area we proposed the application of a flexible waterproofing bandage from BASF. For the visible cracks in the panels we proposed the application of a flexible polyurethane coating, in the form of BASF M808.
Initially all surfaces requiring treatment were prepared by method of vacuum controlled diamond grinding to remove surface laitance and contaminants. Once prepared all surfaces were vacuumed clean.
BASF 933 epoxy adhesive was then applied to prepared surfaces, prior to the embedding of the 930 bandage. To ensure a neat finish both the concrete and the centre of the bandage was masked using tapes.
The cracks and the floor/wall intersection were prepared in the same manner. A small area of stainless steel in the tank doorway was prepared using a Bristle Blaster to raise the necessary profile in order for the coatings to adhere correctly to this difficult substrate.
To ensure the correct climatic conditions and moisture content in the concrete heating and dehumidification was introduced and monitored prior to coating application taking place.
BASF M808 was applied in three coats of contrasting colour as per the manufacturer’s instructions for use. Following application the temperatures were digitally logged to ensure the cure curve was in line with the manufacturers recommendations.
As this application was for the public supply all materials had to be Regulation 31 approved. All of our applicators carry EUSR Blue water hygiene cards as required to work in this environment.
