What is the function of a separation membrane between concrete pavement slab and sub- base

Chetan Yadav

Staff member
What is the function of a separation membrane between concrete pavement slab and sub- base?

Answer: The separation membrane between concrete pavement slab and sub-base has the following functions:
  • It aids in reducing the frictional forces between concrete slab and sub-base and helps to movement of concrete slab with respect to sub-base owing to changes in temperature and moisture.
  • It prevents the loss of cement and water in immature concrete which significantly affects the strength and durability of hardened concrete.
  • It avoids the mixing up of sub-base materials and freshly placed concrete. Polythene sheeting, which is a waterproof material, is commonly used as separation membrane.