Analysis of stability against upheaval of deep excavation by upper bound method considering confined water

Abstract:

Assuming the Prandtl soil slip failure models and considering the confined water, the upper-bound limit analysis theory is used to establish the analysis method of the basal stability against upheaval and checking formula. With the proposed formulas, the effect of the confined water head, the thickness of the impermeable soil layer and the depth of the retaining wall on the stability coefficient are discussed. Calculation results indicate that it is necessary to consider the effect of the confined water on the stability against upheaval of deep excavation; and the safety factor would be smaller with the increase of the confined water head. The comparison demonstrates the applicability of the method used in this paper. The results provide a reasonable calculation method for the design of foundation pit subjected to confined water in soft clay.