Influence of Subgrade Filling Construction and Operation on the Underlying Orthogonal Subway
A three-dimensional finite element numerical model of subgrade pavement-underlying shield tunnel-subgrade soil was established based on the subgrade pavement filling project of a proposed airport expressway to simulate the mechanical response of shield tunnel and subgrade pavement under the coupling effect of subgrade loading construction,operation and train running inside the subway tunnel.The results show that under the action of loading in surface road construction,the maximum values of the vault and inverted arch position of the shield tunnel and the EB-W model solution are 30.0,20.6,27.2 mm,respectively,and the maximum settlement position is located at the middle line of the shield tunnel,and the settlement curve roughly presents a"V"shaped law,in particular,the vertical deformation between-20 and 20 m at the intersection of sungrade and shield tunnel is in the"dangerous value"state.The surface subgrade loading has little effect on the horizontal displacement of the arch waist of the shield tunnel,and the maximum horizontal displacement values of the left and right arch waists of the tunnel are-4.2 mm and 4.0 mm,respectively,which are less than 10.0 mm.After the construction of the surface subgrade,the maximum vertical stress value of the tunnel is about 1.7 MPa.After the completion of the subgrade,the maximum settlement value of the center line of the subgrade is located at the bottom of the subgrade,and its value reaches 7.0 cm.
surface subgradeloading and post-construction operationsunderlying orthogonal linesnumerical simulationpost-construction settlementdeformationprotected area
万方数据
维普
