Utilization of Rice Straw Ash Bio pozzolan as a Partial Replacement for Ordinary Portland Cement (OPC) in Mortar Production

Abstract

The  increasing  demand  for  environmentally  friendly  construction  materials  has encouraged the utilization of agricultural waste as  alternative building materials. This study aims to evaluate the potential of rice straw ash as a bio pozzolan to partially replace Ordinary  Portland  Cement  (OPC)  in  mortar  production.  The  methodology  includes slump flow and compressive strength tests with rice straw ash used at replacement levels of 0%, 10%, 20%, and 30% by weight of OPC. The results show that incorporating rice straw  ash  affects  both  workability  and  compressive  strength  of the  mortar.  The  10% replacement level yielded optimal performance, with a slight decrease in slump flow still within acceptable standards and an improvement in compressive strength compared to the control mix. However, higher replacement levels of 20% and 30% led to a significant reduction in compressive strength, likely due to the incomplete pozzolanic reaction at early curing stages. This study recommends the use of 10% rice straw ash as a partial substitute for OPC in environmentally friendly mortar applications and suggests further research to optimize ash calcination processes and curing conditions to enhance long- term performance.