The Indoor Model Test on the Characteristic of Expansive Soil Slope under Climatic Conditions

Abstract

An indoor model of expansive soil filling slope is tested in Pingdingshan city, Henan province, China. Using temperature and humidity detectors, earth pressure cells and so on, the static evaporation - rainfall infiltration cycles are tracked and monitored in the climate condition. The study suggests that atmospheric temperature is the direct cause of soil temperature. Due to the convection heat transfers, the surface temperature of the soil changes rapidly, and the temperature change of the heat transfer to the interior has a hysteresis phenomenon. Under surface evaporation conditions, the greater the depth is, the smaller the change range is in water content. Water loss rate is related to soil, air flow, temperature and humidity, cracks, soil water holding capacity, permeability and other factors. The change of stress in the expansive soil slope is the result of the joint action of soil water content, nature and climatic conditions. Due to the early erosion of rainfall, soil pressure is obviously attenuated. The soil pressure is on the rise due to the effects of rainfall infiltration and expansion force in the late rainfall. In the engineering, the key to prevent and cure engineering disaster of expansive soil is to improve the deformation characteristics and reasonable drainage of expansive soil.