Clay soils are considered as a problematic soil in term of water absorption rate. The ideas of soil improvement method had been widely used to modify the physical and mechanical properties of clay soil. This study aims to identify the optimum percentage mixing of natural fibers in influencing the compaction characteristics. X - ray fluorescent test (X-RF) and Standard Proctor test has been performed to determine the chemical composition of natural fibers and compaction characteristics of soil samples. Natural fibers such as banana, kenaf, and coconut coir were used as a natural soil stabilizer with varying percentage mixing to increase the properties and stability of soil samples. Experimental data obtained from compaction test shows that the appropriate maximum dry density and optimum moisture content for each natural fiber are at 0.5% natural fibers mixing. In this study, the maximum dry density and optimum moisture content for untreated samples are 1650kg/m3 and 7.8%, respectively. Meanwhile, for treated soil samples that mixed with banana, coconut and kenaf fibers are 1760kg/m3, 1780kg/m3, 1670kg/m3 and 8.2%, 8%, 11%, respectively. Hence, 0.5% mixing with banana fibers indicated the best possible amount of dry density and moisture content among other natural fibers. Therefore, this study proved that natural fibers can act as a good natural soil stabilizer in increasing stability of clay soil.
