Strength Performance of Mortar Prepared with SCBA and RHA as Supplementary Cementitious Materials at Elevated Temperatures

Rapid urbanization emanates from increased cement production, resulting in a significant increase in greenhouse gas emissions and pressure on natural resources. Considering these repercussions, it is critical to explore alternative methods to mitigate cement production by carefully examining sustainable solutions derived from nature. This study provides an in-depth investigation into the performance attributes related to compressive strength when cement mortar is formulated using Rice Husk Ash (RHA) and Sugarcane Bagasse Ash (SCBA) as supplementary cementitious materials. The experimental approach of this study comprises a comparative measurement of the workability and compressive strength of mortar produced by incorporating RHA and SCBA under standard and elevated temperature conditions, specifically at 400 °C, 600 °C, and 800 °C. The use of RHA and SCBA had a significant impact on mortar workability, showing a trend in which an increasing amount of cement substitution led to a decrease in workability. Furthermore, the mechanical performance decreased when up to 10% of the cement was replaced with a blend of RHA and SCBA equally divided by 5%. However, a further increase in the RHA-SCBA percentage corresponded to a decrease in the compressive strength. Upon subjecting both the control and RHA-SCBA cement mortar samples to higher temperatures, an anticipated reduction in the strength was observed. However, the samples containing RHA-SCBA demonstrated strength behavior similar to that of the control specimens when exposed to elevated temperature conditions. Based on the findings of this study, both RHA and SCBA are proposed to have the potential to serve as viable replacement materials for the production of cement mortar.