The Shear Strength of Clay Stabilized with Palm Bunch Ash and Cement

Roads with soft subgrade have low bearing capacity. The result is non-uniform soil settlement. One way to overcome this is with soil stabilization. Stabilization of clay soil is done chemically with palm bunch ash and cement. The purpose of this study was to determine the bearing capacity of soil for the shear strength value of clay soil with variations in mixing 5%, 10%, 15%, 20% oil palm bunch ash, and 10% cement with a 7-day curing period, and then the samples were tested using a direct shear test tool SNI 3420: 2016. The results showed that in the addition of a mixture of oil palm bunch ash and cement with levels of 5%, 10%, 15%, 20%, and 10% cement, the cohesion value increased at a percentage of 20% oil palm bunch ash and 10% cement, namely 0.5448 kg/cm2 compared to the cohesion value in the original soil of 0.0081 kg/cm2, an increase of 98.51%, and a shear angle value of 53.12° while the value of the original soil shear angle was 16.93°. This research concludes that the shear strength value of clay soil stabilized with oil palm bunch ash and cement increases.