Bituminous Concrete (BC) is a hot-mix superior type of bituminous surfacing, having a low voids (3-5 per cent), good durability high imperviousness and good load spreading property. It is used as a surfacing course for modern high traffic roads. The main ingredients and their role are:
Provide stability to the mix by the mechanical interlock.
Fill in the voids in the matrix of the coarse aggregates and add to the stability.
Cement or lime, which stiffens the binder and fills up the voids.