Laboratory Investigation of Lateral Swelling Pressure of Nanning Grey-White Expansive Soil

In this research, the swelling pressure tests under different conditions were carried out on the Nanning grey-white expansive soil. The effects of dry density, initial moisture content and external load on the swelling pressure were investigated. The test results indicate that both lateral swelling pressures are essentially the same, but the vertical swelling pressure is higher than the lateral swelling pressures. For the same dry density, the vertical swelling pressure decreases with the rise in the initial moisture content, while for the same initial moisture content, the vertical swelling pressure increases with the rise in dry density. The lateral swelling pressure increases with the increase in the overlying load. When the lateral swelling pressure decreases, the sliding stability coefficient and overturning stability coefficient of the retaining wall are increased from 0.60 and 1.15 to 1.30 and 1.81, respectively.