Waterproofing of Underground Water Tank

Underground water tanks are susceptible to water ingress from external sources like surrounding soil as well as soluble salts can infiltrate the tank and cause reinforcement attack if not properly waterproof. Our comprehensive waterproofing solutions can keep your structure free from any harmful chemical attack.

PROCEDURE FOR UNDERGROUND WATER TANK WATERPROOFING

  1. TREATMENT BEFORE CONSTRUCTION OF RCC BASE SLAB OF TANK
    1. Repair/Smoothen the surface of PCC by 1:4 Cement Sand mortar.
    2. Apply 2 coats of DURAGARD (cement base polymer/acrylic modified highly flexible waterproof coating). Protect the coating against mechanical damage with 1:4 Cement Sand mortar (admixed with DURA1) of about 15 to 20 mm thickness, as shown in the figure.
  2. CONCRETING
    1. Add DURA 1, an integral water proofing compound confirming to IS:2645, shall be added to concrete to reduce permeability and increase the durability. The dosage of DURA 1 is 2% by weight of cement i.e. 1 kg for 50 kg bag of cement.
    2. DURAKRIT (hardening-cum-bonding agent) shall be used wherever the construction joints are coming. On the existing surface, Cement : Sand slurry shall be applied admixed with DURAKRIT in the ratio Cement : Sand : DURAKRIT mix :: 1:1 : 0.6.The green concrete is placed before the above slurry dries.
  3. SURFACE PREPARATION
    1. If honeycombs and voids are found in the retaining wall or slab, grouting has to be done through nozzles fixed at 1 m center-to-center with non-shrinking expansive grout, DURA EV.
    2. Make the surface free of oil, grease or any loosely adhering particles.
    3. Repair the substrate with rich mortar and DURAKRIT if there are any cracks (more than 1mm wide), pin holes, honeycombs, etc.
    4. Round all horizontal and vertical edges by making a mortar gola with rich mortar and DURAKRIT as per the specification of "Mortar Gola".
  4. TREATMENT AFTER CASTING RETAINING WALL & BASE SLAB
    1. Apply 2 coats of DURAGARD (cement based polymer/acrylic modified highly flexible waterproof coating) from inside and outside. The coating must be provided at right angles to each other after the previous coat is touch dry.
    2. The above treatment shall be provided from inside and outside to keep out water from external sources.
    3. Water leakage test in full supply level will be carried out as per IS 3370 part 1 for seven days as instructed.
    4. Protect the coating by laying glazed tiles/cement sand plaster admixed with DURA 1 @ 1 kg for 50 kg bag of cement.