The effect of lime and phosphoric acid on the CBR value of soft soil based on curing time

Abstract

Road construction, both for flexible and rigid pavements, needs to pay attention to the bearing capacity of the subgrade. Especially on soft clay soils. The method to determine the bearing capacity value is through CBR testing in the laboratory. Soft soil has a low bearing capacity, so it cannot accept the load acting on it, such as the soil in the Gedebage area of Bandung. Because the carrying capacity value is decreasing, it is necessary to improve the soil with soil stabilization methods. In this research, stabilization materials will be used in the form of lime with a percentage of 10% and phosphoric acid 5%. Aiming to increase the bearing capacity value of the soil based on the results of laboratory CBR tests with 3, 7, and 14 days of curing, as well as to determine the optimum curing period of the test. Based on the test results, very positive results were obtained because it can increase the soaked CBR of 0.8% and 3% unsoaked for the native soil to 5.6% for soaked and 15.23% for unsoaked CBR in soil that has been stabilized with a 14-day curing period. Thus, these stabilization results meet the minimum requirements for pavement subgrade.