Repairs to R.C.C. structures is often been taken as a process of just filling up the damaged section of concrete with new concrete. It is necessary that the extent of damage should be properly scrutinized and proper technique with the use of right materials are used in this process. safety measures of propping the section as required should not be forgotten.

 

Once the repair areas have been marked; certain guide lines and methodology should be followed as under to obtain reasonably good results.

 

Remove the loose concrete completely.

 
Clean the exposed reinforcement by wire brushing or by mechanical means.
 
Apply a rust removing solution i.e. RUSTICIDE by brush to reinforcement steel. If the reinforcement has corroded more than 20% of the actual size, attach new reinforcement along the old one by welding.


After 24 hours of application of RUSTICIDE, apply two rust passivating coating of POLYALK FIXOPRIME / cement slurry in 1:1.25 proportion (by weight) to chemically de-rusted surface of steel by brush at an interval of 4-6 hours.

Clean the entire broken surface thoroughly and moisten.

Apply priming cum bonding coat of POLYALK EP / Cement slurry in 1:0.5 proportion (by weight) to damaged concrete surface by brush.

 Immediately (wet on wet) Place Polymer Modified by hand on the above primed surface in thickness of 10-15 mm for each layer. The mixing of polymer modified mortar is in the proportion of
  • 1 kg. POLYALK EP.
  • 5 kg. Cement.
  • 15 kg. Graded Quartz Sand.
  • Add water (@ 1L) to attain dough like consistency.

If the broken concrete thickness is more than 20 mm, apply in layers of polymer modified mortar as per the procedures above till to build the desired size / section.

 After 24-48 hours of application of mortar cure by sprinkling the water on the surface.