Simulation of Internal Force Change in Subway Tunnel under Different Stratum Disturbance Conditions
The excavation of the foundation pit around the subway may cause the internal force changes of the tunnel lining structure,so a reliable safety assessment should be carried out.This study relies on a case study of large-scale foundation pit excavation near a metro Line 3 subway station in a city,and adopts MIDAS-GTS-NX software to conduct finite element analy-sis of four different excavation stages.The results show that the bending moment,shear force and axial force of shield tunnel change during foundation pit excavation.The maximum change value of bending moment is 3 kN.m/m,the maximum change value of shear force is 2.5 kN/m,the maximum change value of axial force is 20 kN/m,and the maximum change ratio of inter-nal force shear is 4.3%.It can be considered that the internal force change value is at a low level,and the excavation of founda-tion pit has little influence on the internal force state of shield tunnel.Because the change of force of subway structure is at a low level,it can be considered that the construction of deep foundation pit does not endanger the safety of adjacent subway structure.
subway tunnelsdeep excavationsMIDASinternal force chang
万方数据
维普
