Comparative analysis of the properties of composite mortar with addition of rubber powder from worn tires

This study compares the performance of two plastering mortars. The first one was produced at a 1:6 proportion of quicklime powder and sand (by volume) and ripened. The second had the same proportion but underwent a water withdrawal process in the oven. The mortars were given the same content of cement, making the proportion 1:1.5:9 (by volume), and the addition of rubber powder from worn tires at the proportions of 6%, 8%, 10% and 12% by aggregate volume. Axial compressive strength, flexural strength, deformation energy, void content, water absorption by capillarity, restrained shrinkage, and tensile bond strength were measured. The results showed that the second mortar, with rubber waste, performed better than the ripened mortar. With a reduction in the absorption of water by capillarity in the restrained shrinkage and in the void content, it maintained the tensile bond strength. The energy of deformation rose, although the compressive strength dropped.