Development of a plastering mortar using waste bagasse and rice husk ashes with sound mechanical and thermal properties

Abstract

The concept of using cleaner production technologies has become prominent in the present context for achieving sustainability in construction. Incorporating agricultural waste as cement replacements has shown enhanced mechanical and durability properties of the resulting mortar. A comparative study on the mechanical, thermal and environmental performance of a newly developed lightweight mortar containing agro-wastes namely Bagasse Ash (BA) and Rice Husk Ash (RHA) were investigated. Ordinary Portland Cement was partially replaced by BA at dosages of 0%, 5%, 15%, 20%, and 30% and RHA at dosages of 0%, 5%, and 15% by weight. A detailed investigation was carried out to determine the optimum material mix design which achieved good material properties. Results indicated that the addition of 30% BA as a partial replacement for cement improved the thermal performance by causing a 33% decrease in the thermal conductivity. Additions up to 30% of BA or 15% each from RHA and BA can be used to obtain mortar with compressive strengths complying with the standard values. At the same time, the combination of BA and RHA (15% each) decreased the thermal conductivity up to 31% compared to the conventional mortar. Further, the environmental assessment indicated that incorporation of BA and RHA in mortar can significantly reduce greenhouse gas emissions (i.e., 28% reduction per kg of BA).