Effect of masonry residue on the hydration of portland cement paste

Abstract

This paper presents the results of an experimental study about the effect of the incorporation of masonry residue (RM) from construction and demolition wastes (RCD) on the hydration of cementitious pastes. Kinetics of the exothermic reactions during early stage of hydration was monitored by calorimetry and the presence of hydration products was determined by scanning electron microscopy (SEM), thermogravimetry analysis (DTG), X-ray diffractometry (XRD) and Fourier-transform infrared (FTIR). The results indicate that the presence of RM in the pastes does to decrease the heat of hydration in the first 48 hours. On the other hand, the SEM, DTG, XRD and FTIR techniques indicate that the main hydration products in the pastes added with RM are calcium silicate hydrates (C-S-H), calcium aluminate hydrates (CAH) and calcium aluminum silicate hydrates (CASH).