Kaolinite subgrade strength characteristics variation with RBI Grade 81

Abstract

The shrinking behaviour of clay soil due to moisture variation causes damage to the foundation of structures, residential, commercial structures and embankment construction. To overcome this problem, the soil needs to be treated to improve its strength and durability of the ground. The best technique is stabilization, which enhances the engineering soil properties, upgrades the shear strength, and reduces the consistency limit. In this present study, Kaolinite clayey subgrade soil is stabilized using Road Building International Grade 81 (RBI), and its effects on the strength characteristics of the soil are studied. Compaction characteristics, Atterberg's limits, Unconfined Compression Strength tests (UCS), and Split Tensile Strength (STS) on the soil samples were performed. The same composites are studied for SEM and XRD results to confirm the morphology of the new compounds formed. Compaction factors increased optimum moisture content (OMC), and the maximum dry density (MDD) decreased with RBI Grade 81 to kaolinite. UCS values increased significantly for the clayey subgrade with the addition of RBI Grade 81. RBI Grade 81 at 8% shows an enhanced upgrade in the clay subgrade's strength compared with the natural kaolinite subgrade. Hence, RBI Grade 81 can be recommended as a potential soil stabilizing agent, particularly for clayey subgrade soil.