Study on Characteristic of Laterite Soil with Lime Stabilization as a Road Foundation

Regional growth and development led to an increase in infrastructure especially roads. Along with that, material requirements as the road foundation also increased. Meanwhile, the number of qualified materials in certain areas is limited, difficult to obtain and expensive. Therefore, efforts are required to exploit the potential of local soils as a
qualified road foundation material. One of them is laterite soil which is only wasted from mining activities. This study aims to analyze and produce the characteristics of laterite soil with lime stabilization to be used as a road foundation. Physical and mechanical properties, mineral content, and chemical composition, obtained from laboratory testing. Meanwhile, to obtain soil bearing capacity, the physical model of the road foundation was examined. The addition of lime with compositions of 3, 5, 7, and 10% at maximum dry density from Proctor standard test, then cured to 3, 7, 14, and 28 days before testing. Subsequently, the soil mixture is fed into the test tub with length (L) = 8m, width (W) = 2m, and height (H) = 2.5m. The physical model of road foundation consists of a subgrade soil with 1.5 m thickness and above the subgrade is placed lime treated base with 0.1 m thickness. Dial gauge to read the magnitute of vertical deformation occurs when loading is placed on surface with 0.2 m distance. Furthermore, static loading test on each mixture of lime treated base. The results show that, stabilization of 10% lime for 28 days curing time yields the strength and bearing capacity of the soil three times higher than soil before stabilization. Subgrade modulus increased significantly with increasing of lime content and curing time. Comparing the relation of subgrade modulus and CBR values for common soil and sediment soil with cement stabilization, it was found that performance of laterite soil with lime stabilization is better than sediment soil with cement stabilization and approaching of common soil. It is concluded that laterite soil with lime stabilization has potential as a road foundation.