The Strength, Microstructure, and ecological assessment of concrete mix incorporating waste glass powder and polypropylene fiber

Abstract

Using waste glass powder (WGP) as a source of silica in the production of cement-based materials could form denser matrix and address the ecological challenge of its deposition. This study introduces two grades of fineness of WGP: fine glass powder (FGP) and ultrafine glass powder (UFG) as 5 % and 10 % substitution for cement in the production of concrete reinforced by polypropylene (PP) fiber. Nine concrete mixes are investigated for their mechanical and ecological performances. Additionally, the study of mixes’ microstructure is reported to observe the influence of WGP and PP fibers contributions on the hardened matrix. ‌Based upon the results, FGP incorporation significantly enhances the FRC compressive strength from 7 to 90 days (between 40 % and 60 %). However, the highest mechanical performance is achieved by 10 % UFG as cement replacement and 0.5 % PP fiber inclusion. Moreover, scanning electron microscope (SEM) results show more chemical activity of UFG, and less calcium hydroxide presented in the hardened matrix. In terms of ecological concerns, between 5 % and 10 % lower CO2 and SO2 emissions and water usage indices for proposed concrete mixes containing WGP, and PP fiber are obtained, while the required energy consumption for preparing these mixes significantly increases (around 15–45 %) due to UFG and PP fiber incorporation in FRC.