Analytical solution of steady seepage field of foundation pit considering thickness of retaining wall

The two-dimensional steady-state seepage field of a foundation pit in an isotropic soil layer supported by a suspended retaining wall considering thickness is analytically studied. The distribution of water head in the five regions is expressed in the form of a graded solution by using the superposition method and the method of separation of variables, and the explicit analytical solution of the seepage field around the pit is derived by combining the continuity conditions between the regions. Compared with the angle-preserving transform solution, this analytical solution can directly solve the values of water head at any point inside and outside the pit without generating singularities. The correctness of the analytical solution is verified by comparing with the calculated results of the water head obtained from the finite element software. The distribution of total water head obtained from the analytical solution of this paper is curved. The factors such as the inner width of the pit, the distance from the top of the impermeable layer to the bottom of the retaining wall, the water level in the pit and the thickness of the retaining wall have a great influence on the distribution of water head of the pit. As the thickness of the retaining wall increases, the water heads in the far field of the seepage field of the pit and the bottom of the retaining wall change more, and the maximum hydraulic gradient drops to the bottom of the retaining wall. Compared with the flow network methods in one-dimensional seepage and two-dimensional seepage and the proposed analytical solution without considering the thickness of the retaining wall, it is more accurate to calculate the water pressure in the design by using the analytical solution of two-dimensional seepage considering the thickness of the retaining wall.