The Stability of Unsaturated Soil Foundation Pit Reinforced with the Cement-Mixed Sheet Pile Wall

The non-uniform distribution of matric suction in the unsaturated soil has a great impact on the stability of the unsaturated soil foundation pit. By means of the strength reduction finite element method, the stability of the unsaturated soil foundation pit reinforced with the cement-mixed sheet pile wall was analyzed. The overall safety factor of the unsaturated soil foundation pit reinforced with the cement-mixed sheet pile wall is greatly reduced and the position of potential sliding surface goes upward with the gradually decreasing of matric suction. With the constant height of the cement-mixed sheet pile wall, the shallower the embedding depth of the cement-mixed sheet pile wall is, the smaller the safety factor of the foundation pit slope is. The results show that the safety factor of the overall stability of the unsaturated soil foundation pit decreases with the deep excavation and the gradually decreasing of the matric suction.