Abstract: Construction joint, which is resulted from underground diaphragm wall construction to deal with complex geological foundation for hydropower project, is a difficulty in engineering because it affects the overall mechanical properties of the underground diaphragm wall. According to the real geological conditions under the last part of diaphragm wall of Tongzilin hydropower project, we established finite element models of sash-shaped underground diaphragm wall with three different kinds of joints (rigid joints, hinged joints and semi-free joints). The stress and deformation of the wall respectively with these three kinds of joints were analyzed and compared under the most adverse working condition in ABAQUS non-linear simulation. The influence of joint on the stress and deformation of underground diaphragm wall was obtained. The result is a reference for similar projects.

Key words: sash-shaped diaphragm wall, joint, non-linear, FEM, stress and deformation