Abstract:

 Taking the construction of Guomao station of Beijing Metro as example, the author studies and analyzes, by means of field measurement method, the main rules and effect factors that induce settlement and deformation of surrounding strata as well as crown settlement and ground surface deformation of largespan separate Metro station constructed by PileBeamArch method. The study result shows that the longitudinal stratum settlement can be divided into earlier settlement area, rapid settlement area and reducing settlement area. Rapid settlement area consists of heading construction stage, supporting arch stage and lower soil excavation stage; The traverse settlement accords with Peck curve and its influence scope is 3 to 4 times of the tunnel diameter. The main crown settlement happens in the supporting arch stage and lower soil excavation stage, which corresponds to the ground surface deformation. If the supporting arch construction, lower soil excavation and steel supporting are carried out duly, the sustaining soil deformation can be prevented effectively.