The role of scrap rubber particles on the drying shrinkage and mechanical properties of self-consolidating mortars

This study presents the results of an experimental investigation to study the effects of partial replacement of fine aggregate with scrap tire-rubber in self-consolidating mortar (SCM). Fresh and hardened properties of SCMs produced at five different replacement ratios of scrap rubber with sand, 0%, 10%, 20%, 30%, 40% and 50% (by weight of sand), were compared to those of without rubber. Mini slump flow and mini V-box flow time values were determined experimentally in fresh SCM. Moreover, drying shrinkage, apparent porosity, water absorption by weight, compressive and flexural strength, and dynamic modulus of elasticity were measured. While comparing the control SCMs, the partial replacement of scrap rubber with sand resulted in degradation in fresh and hardened properties. On the other hand, the addition of scrap rubber, from 10% to 40%, had a beneficial effect in decreasing the drying shrinkage of SCMs produced at low w/p (water-powder) ratios.