Impact of rice husk ash on compressed cement-lateritic brick durability and microstructural characteristics

Abstract

One of the potential ways to lower building costs and improve the quality of the environment in both urban and rural regions is to use local resources as a substitute for cement in building construction. The purpose of this study was to determine how Rice Husk Ash (RHA) affected the morphology and durability of cement-lateritic bricks. Analytical techniques were utilized in the lab to ascertain the RHA's chemical make-up. Compressed Earth Bricks (CEB) were created by employing water content of 20 to 25 percent and replacing 0 to 5 percent of the cement with 0 to 5 percent of RHA. Response Surface Methodology (RSM) of Design Expert software was used to create seventeen (17) variables for the CEB manufacture.The created CEBs underwent compressive strength and microstructural studies in the lab after being cured for 28, 56, and 108 days. According to the results, RHA is a powerful pozzolan with a high SiO2 concentration that might potentially replace non-renewable silica as one of the primary cement sources of oxide that pozzolans react with. Most samples exhibit an increase in compressive strength with longer curing times and have a minimum strength of 1.65 N/mm2 or higher.The microstructural study of the pozzolan revealed that it contains tiny particles. Consequently, as the curing age increased, the porosities decreased and the compressive strength of the stabilized bricks improved. In conclusion, the finest CEBs for building construction are those produced with 1.25 percent RHA and 23.75 percent water content.