Utilization of Untreated Agricultural Waste Ashes Used as a Partial Fine Aggregate Substitution for Cement Mortar

In various countries, construction materials have immensely increased due to rapid urbanization, leading to extremely high demand for natural resources. In general, many countries rely on concrete as their main construction material. Therefore, the demand for natural resources continues to rise, such as cement, fine aggregate, and coarse aggregate. In addition, the agricultural sector works to sustain the economy and provide the essential needs of communities. This sector produces various wastes that have not been sufficiently utilized. This study attempted to utilize agricultural wastes as substitutes for fine aggregate in cement mortar. The agricultural wastes used in this study consist of the sugarcane farm (bagasse ash), the rice farm (rice husk ash), and the corn farm (cob corn ash). Utilization of these wastes aims to reduce the exploitation of sand as fine aggregate for the production of mortar and to increase the amount of agricultural wastes to be sufficiently utilized. Experiments on the laboratory scale were conducted to measure the fresh and hardened properties of cement mortar. Fresh properties were evaluated using the slump flow test, while hardened properties were evaluated by compressive strength, porosity, water absorption, and mass loss. In addition, non-destructive tests, including rebound hammer and ultrasonic pulse velocity tests, were conducted. The compressive strength results decreased as the amount of agricultural waste increased during early ages. However, the compressive strength increased significantly when the amount of agricultural waste increased at 28 days as a curing period. This investigation indicates that introducing agricultural wastes for additional mortar materials can improve its compressive strength and other properties. However, appropriate mix proportions are required to produce highperformance mortar.