Synergistic Effect of Recycled Powder and Waste Glass Powder on the Properties of Cement Paste

Abstract

Cement paste was prepared by recycled powder (RP) and waste glass power (WGP) using simplex centroid design method. By measuring the fluidity, setting process and bleeding rate of paste, as well as the compressive strength of specimen, the synergistic effect of RP and WGP on the properties of cement paste was discussed. The reaction mechanism and microstructure were explored by X-ray diffraction and scanning electron microscopy. The results indicate that the addition of RP could significantly reduce the fluidity, setting time and bleeding rate of paste, while WGP can obviously improve the rheological property and play a retarding role. The workability of paste can be effectively regulated by mixing RP and WGP together. RP contributes a lot to the early strength, whereas WGP could provide a strong support for the later strength. R10W10 has a favorable strength development. In the ternary system, cement can rapidly hydrate and form a skeleton structure. RP plays a good role in filling the structure, and the pozzolanic reaction of WGP makes the microstructure more compact. The incorporation of cement, RP and WGP can promote the growth of hydration products, improve the density of microstructure, and form a certain synergistic effect.

Keywords: recycled powder, waste glass powder, synergistic effect, reaction mechanism