Investigation on the mechanical and durability properties of the epoxy resin fly ash polymer mortar

Epoxy resin is well-known for its outstanding mechanical properties, durability, and flexibility in advanced construction materials. This study examines the synergistic potential of epoxy-based composites incorporating fly ash as a partial sand substitute to enhance material performance and mitigate environmental challenges. The study examines the fresh, mechanical, and durability properties of epoxy resin fly ash-based polymer mortars (ERFPM) with epoxy reinforcement in the range of 18–25 wt.%, and sand was replaced with fly ash in the range of 10–20 wt.%. The study demonstrates that increasing the sand replacement from 0% to 10–20% yields substantial improvements in both flexural and tensile strength. The experimental results indicate that the polymer mortar (PM) formulation consists of 25 wt.% epoxy resin (ER) and 20 wt.%. Fly ash (F) shows superior mechanical performance, attaining a compressive strength of 68.12 N/mm 2 , a flexural strength of 17.22 N/mm 2 , and a tensile strength of 8.85 N/mm 2 at 28 days of curing. In contrast, moderate improvements in mechanical properties were observed in ER 20-F10 PM, ER 22-F10 PM, and ER 25-F10 PM when compared to the control specimens without fly ash. Moreover, enhanced abrasion resistance is evident in specimens with higher fly ash content, as indicated by minimal mass loss (0.030%, ER 25-F20 PM). The ERFPM also demonstrates significant chemical durability against aggressive agents, such as sodium chloride and sodium hydroxide, thereby improving its compressive strength. However, exposure to magnesium sulfate results in a 4.47% reduction in strength in ER 20-F20 PM after 90 days.