Abstract：
The advantages, disadvantages and applicability of common calculation methods for aseismic analysis of metro tunnels are briefly described. A finite-element model is established based on the People′s Hall Station of Qingdao metro line 4, and the dynamic characteristics of a metro station under a seismic load is calculated and analyzed.A comparison of the internal force and displacement at each point of the structure shows: 1) the seismic response results calculated by the response displacement method and response acceleration method are generally larger than those calculated by the time- history method, and the greater the station stiffness, the larger the difference; 2) in light of a large elastic-plastic constitutive error of the structure under an E3 state, the elastic-plastic interlayer displacement can be obtained by multiplying the elastic interlayer displacement and ductility coefficient for the station in the simple stratum; 3) the results calculated by the inertia force method are generally larger than those calculated by the response displacement method, while the difference is small if the station inertia force plays a leading role (i.e.,the station stiffness is very great with respect to the soil mass); 4) the Qingdao station is basically located in granite,with 90% of the structure dynamic response caused by shear force, so the aseismic analysis results of the soil mass are different from those of Kunming, Changzhou and Zhengzhou; and 5) the interlayer displacement angle of the metro structure increases with an increase of the station overburden but decreases with an increase of the rise-span ratio, elastic modulus of the rock mass and thickness of the secondary lining, while the thickness of the secondary lining has little effect on the angle of the interlayer displacement and the station overburden has greatest effect on the angle of the interlayer displacement.
2017, Vol. 54 