Replacement concrete should be capable of mitigating carbonation and corrosion.

The replacement material should be least affected by temperature and moisture changes. In other words volume changes (shrinkage) should be minimized.

As far as possible replacement concrete should have the modulus of elasticity more or less similar to that of existing old concrete.

Replacement material should, as far as possible, shrink less to avoid separation causing shear at the interface between old and new concrete.

Compressive strength of replacement material and old concrete should be of the same order.

Compressive strength of replacement material and old concrete should be of the same order.