Deformation characteristics of latticed diaphragm wall in revetment foundation trench for one immersed tunnel

In this paper, based on the excavation of revetment foundation trench of an immersed tunnel project in Guangzhou, China, the influence of the insertion ratio of latticed diaphragm wall, the thickness of muddy layer under the bottom of foundation trench, the grading excavation of foundation trench and the construction of undercrossing shield tunnel are considered respectively, to study the deformation characteristics of diaphragm wall by three-dimensional numerical simulation. In addition, the finite element strength reduction method is used to analyse the stability of the latticed diaphragm wall. The results show that: the maximum lateral deformation of the latticed diaphragm wall decreases with the increase of the insertion ratio. When the insertion ratio rises to about 0.63, the lateral deformation will change slightly from then on; The increasing thickness of muddy layer has more and more influence on the lateral deformation of diaphragm wall; The deformation of diaphragm wall mainly comes from the excavation of foundation trench, and is very little affected by the excavation of the shield tunnel; Under actual working condition, the safety factor of diaphragm wall calculated by strength reduction method is about 4.1 also.