关键词: 单层支撑, 基坑, 承压水, 抗倾覆稳定性

Abstract: The overturning stability check is very important in the single layer supporting structure for the deep excavations. The formula of quantifying the influence of the artesian groundwater on both sides of the supporting structure were deduced based on the influence of artesian groundwater on the overburden stress of above soils so that the effect of artesian groundwater on the stability of the single layer deep excavation structure can be evaluated. The results indicate that an adverse effect of the artesian groundwater on the stability of the supporting deep excavation structure could be concluded. Factors that might affect the stability are head of the artesian groundwater, distance between the bottom of aquitard soil layer to the bottom of deep excavation and the thickness of the aquitard. Throughout out the engineering practice, measures such as, lowering the groundwater head and improving the sealing at the bottom of the excavation can effectively reduce the effect of artesian groundwater on the stability the supporting structures. It is further suggested that the future design code should consider the effect of the artesian groundwater on the stability of the supporting structures for deep excavations.

Key words: single-layer supporting structure, deep excavation, artesian groundwater, overturning stability