The Effects Of Rice Husk Ash Substitution On Physical And Mechanical Properties Of Clay (Peer Review)

Clay is a soil with poor characteristics, which include low weight bearing capacity h ence it needs to be fixed. Stabilization is a soil improvement technique, involving the use of cement for increase bearing capacity. H owev er the high cost of cement, led to the investigation of other alternatives, e.g. Rice husk ash (RHA), a pozzolanic ag r icultural waste, which contains a lot of silica, processed by burning husk ash. This study therefore analyses the effect of substituting RHA on the physical and mechanical property of clay, in an attempt to increase the value of its carryi ng capacity. Laboratory scale testing was based on ASTM standards, which include California Bearing Ratio (CBR) and Unconfined Compression Test (UCT). The variation of RHA applied to the sample were 3%, 6%, 9%, 12% and 15% of the soil (dry density ), at a curing period of 0 , 3 and 7 days. The results further showed that the optimum value of UCT (1.05 kg / cm²), was obtained at 6% RHA, within a 7 day curing period. The optimum CBR value (13.12%) was obtained with the unsoaked mixture at 9%, with a 7 day curing period.