Effect of limestone powder substitution on mechanical properties and durability of slender precast components of structural mortar

The use of structural mortars on slender components is already widely spread. However, due to the current demand, the high consumption of cement is the primarily responsible for carbon emissions and for cost increase. The objective of this research is to study the effect of partial substitution (0 %, 9 %, 16 %, 23 % and 30 %) of cement by limestone powder focusing on slender precast structures, natural sand, Portland Cement CP-V, limestone powder and a polycarboxylate superplasticizer were used. It measured mini-cone slump flow test, mass density at fresh and hardened state, water absorption index, porosity, modulus of elasticity, compressive strength and electrical resistivity. It is noticed that the substitution content significantly influences the properties also the durability parameters are more affected than mechanical properties. The restrictive property was the water absorption index, allowing the cement substitution by limestone powder up to 11 % to maintain mortar properties according to standards.