The circular underground diaphragm wall supporting structure with three-dimensional arch effect is gradually used in foundation pit projects because of its better resistance to deformation and load-bearing capacity.But it also faces problems such as complex force deformation of the wall，various calculation methods，and uncertainty in the value of circumferential stiffness.In this paper，taking the 65 m diameter circular accident emergency pool ground connection wall support in Lanshan port area as an example，the two-dimensional m-value method and the three-dimensional m-value method were used to model and analyze considering the annular equivalent stiffness respectively，and compared with the actual measured data.The results show that the structures have strong spatial effects，and the lateral deformation and vertical bending moment derived from two-dimensional calculation are relatively large，while three-dimensional calculation can more realistically simulate the excavation process.When the two-dimensional m-value method is used，it is more appropriate to take 0.8 for the circumferential stiffness reduction factor，and 0.5 for the three-dimensional m-value method.When the circular ground link wall support is used，it is more reasonable to use static earth pressure after the wall.