The new Aykon One development in South London required seamless and hygienic tank linings for its two cold water storage tanks.
Initially all concrete surfaces were prepared by method of vacuum controlled diamond grinding to remove surface laitance and contamination. Whilst this was extremely effective, this preparation exposed numerous blow holes as is common in site cast concrete.
To overcome this once prepared and thoroughly cleaned a cementitious fairing coat in the form of Flexcrete 844 SP was applied throughout both of the water tanks. This is essential when installing tank linings in concrete storage tanks as you cannot fill blow holes with paint alone.
The cementitious fairing coat was allowed to set and hydrate until it reached below 16% on the wood moisture equivalent scale as recommended by the tank lining manufacturer. This was tested and recorded using a Protimeter moisture gauge.
As per our standard quality assurance the climatic conditions within the tanks was checked frequently during coating application to ensure correct adhesion and curing of the new tank linings.
All the internal corners were rounded using a polyurethane jointing compound prior to the application of Spencer Coatings LV sealer by method of brush and roller.
This was followed by the application of two further coats of Spencer Coatings Acothane at a nominal thickness of 500 microns per coat.
As per best tank lining practice, each coat was applied in a contrasting colour to ensure uniform coverage of the new tank linings.
Finally as part of our standard tank lining quality assurance a DC holiday spark test was undertaken to check for pin holing and porosity. Where found these were marked with chalk, prior to touching in using the same tank lining material applied by brush.