Stability Analysis of Foundation Pit Under Bottom Over-Excavation and Top Overloading Conditions

The soil nailing wall is a common support method used in foundation pit supporting system. The overloading and over-excavation maybe be met during the processing of excavating and those all effect the stability of foundation pit. The effect of over-excavation and overloading on foundation pit stability are analyzed in this paper using FEM combined with the project in Luoyang city. The results show that local over-excavation may form a continuous slip surface in slope and lead to instability of foundation pit. The external load on the slope top may lead to greater lateral displacement and settlement. The distribution area of settlement under external load shows as triangular and the maximum depth is almost equal to load width. The overloading on the top of foundation pit may accelerate collapse processing when the toe of slope is over excavated, but over excavation still may lead to instability of foundation pit although no overloading on the top. This should be paid more attention in project.