Analysis of clay improvement as subgrade using Palm Oil Fuel Ash (Pofa)

Abstract Road construction on clay soils often causes problems, because have a low bearing capacity and high swelling shrinkage values. Damage to roads soft cannot be avoided; therefore, soil improvement is necessary. Soil stabilization one of the efforts improve properties, aim increase soil. So far, stabilizing materials commonly used for are cement lime. In study, oil shell waste in form palm fuel ash (pofa) will as agent. Pofa industrial wastes that contain percentage silica (Si). The (Si) content beneficial reducing properties soils. study was 4%, 8%, 12%, 16%, 20% total weight curing time sample seven days with unsoaked soaked (four days) conditions. results this indicate mixing pofa can CBR value decrease clay.