Underside of bridge deck, railing, etc. of bridges and Piers and Substructures which are not in River Bed
Cleaning and drying the surface; applying (@ 0.30 litre per square metre) a coat (DFT of 100-150 micron) of a translucent brown coloured modified phenolic resin based single component high performance polymeric waterproofing compound (sp. gr. 0.87, rosin content nil and a solid content of minimum 0.47%), e.g., PERMAPROOF, with demonstrable properties of resistance to water and acid; applying (@ 0.25 litre per square metre) a top coat of a modified phenolic resin based single component waterproofing compound of grey or other shades (sp. gr. 0.85), e.g., PERMACIL-GA, before the base coat becomes tack-free; permitting the coatings to cure and dry naturally; the 2-coat system shall be impermeable under a waterhead of 20.0 metres.
Cleaning the surface; preparing the surface by acid etching; treating the surface with a two-layer plaster; the first layer shall be 5 mm thick with cement (OPC or slag), admixed with an octadecanoic acid based cementitious waterproofing compound (bulk density not greater than 0.5 gm/cc, moisture content not greater than 2.0% and free fatty acid not greater than 0.2%), e.g., PERMAKAR 3, in the weight ratio of 50:3 for cement and waterproofing compound, further admixed with specially fabricated deformed galvanized steel fibre (@ 150 gm per square metre of treatment surface), e.g., KARFIB; finally providing a 12 mm thick cement-sand (1:2.5) plaster, enriched with polyester fibre, and curing the plastered surface; the treatment shall be impermeable under a waterhead of 20.0 metres.