Research Progress on Seepage Coupling Theory of Super deep Foundation Pit Engineering

Abstract:

The seepage coupling model, the seepage theory, and the soil permeability as well as the influence of dewatering on soil strength were analyzed and discussed based on a summery of seepage coupling theory of foundation pit engineering at home and abroad. Results show that the seepage coupling model can not only reflect complex stress path and nonlinear characteristics of soil, but also can reflect the interaction of seepage field and stress field due to deep depth of excavation, large scale of excavation and complex retaining system of super deep foundation pit engineering. Under the effect of high hydraulic gradients, the seepage of super deep foundation pit engineering may deviate from the Darcy law, and the permeability coefficient of the mixed soil composed by unsaturated soil, saturated soil and water resisting layer is no longer a constant, but the function of strain filed. Test results show that the influence of dewatering of super deep foundation pit engineering on soil strength cann’t be ignored, therefore, it is an important research field about seepage coupling analysis of super deep foundation pit engineering that explores quantitative relationship between the amount of dewatering and strength parameters of soil. In conclusion, in order to meet the needs of engineering practice, it is urgent for seepage coupling analysis of super deep foundation pit engineering to make improvement and innovation in the seepage coupling model, the seepage theory, the dynamic change of permeability coefficients and so on.