Abstract：Single diaphragm wall is one of excavation supporting structures that are greatly recommended in Guangzhou Metro Project. Compared with the supporting structure of circular cast-in-place piles，it has many advantages in structure. In this paper，a method is put forward in which straight beam element is employed to simulate the supporting wall and a kind of rotational Goodman interface element is employed to simulate the behavior of interface between the soil and the supporting wall. The method of calculation and the stiffness matrix of the elements for the supporting wall and the interface elements are analyzed with 2D FEM. In the Ergong Station excavation of single diaphragm wall of Guangzhou Metro Project，the analysis involves the distribution of displacements and bending moments of supporting structure，the settlement of ambient soil and the distributions of the plastic zones and principal stresses. The calculation results are compared with those measured in-situ，and show that they match with the latter very well.
