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

Abstract

Today, the production of Portland cement (PC) 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 environment. To minimize the harmful effect of the PC on the environment, it is used in concrete mixtrues by displacing it in specific proportions with different industrial wastes. Using industrial wastes such as fly ash (FA), silica fume (SF), and marble powder (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 the effects of FA, SF, and MP comparatively replaced with cement at the rates of 10%, 20%, and 30% on the flowability, mass loss (ML), and residual compressive strength (RCS) of mortars before and after freeze-thaw (FT) 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 MPadded 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%.