Physical and mechanical properties of pozzolanic materials blended cement mortars before and after the freeze-thaw cycles

Abstract

Today, Portland cement (PC) production causes a significant release of carbon dioxide (CO2) gas into the atmosphere. The CO2 gases released into the atmosphere create environmental pollution worldwide and prevent current and future generations from living in a cleaner nature. One of the most effective ways of restricting PC use in concrete mixes is to use different types of industrial wastes by replacing them with PC. Using industrial wastes such as fly ash (FA), SF, and MP in concrete mixtures by replacing cement in specific proportions is vital in terms of sustainability. The primary purpose of this study is to examine comparatively the effects of fly ash (FA), silica fume (SF), and marble powder (MP) replaced with cement at the rate of 10%, 20%, and 30% on the flowability, mass loss, and residual compressive strength (RCS) of mortars before and after F-T cycles. According to the results, the effects of FA, SF, and MP on mortars' fresh and hardened properties vary considerably. However, using FA, SF, and MP instead of cement significantly improves the matrix's weak cement/aggregate interface transition zones (ITZ) by showing the filler effect. They contribute considerably to reducing mass losses and increasing the RCS capacities of mortars. Compared to room conditions, the reduction in RCS capacities of the control mortar was 21.32% after 200 F-T cycles, while the decrease in RCS capacities of FA-, SD-, and MP-added mortars was between 7.86 and 19.85%. While the mass loss of the control sample after the 200 F-T cycle is 1.23%, the mass loss of mortars with FA, SF, and MP additives is lower and varies between 0.44% and 1.02%.