Abstract The basic principles, analytical method and problems regarding the conventional response displacement method are described. The formulas of formation spring stiffness are given with the assumption of both a slip and noslip contact surface, and a generalized response displacement method is put forward based on the formation-structure model. As for this method, the seismic force displacement is applied on the boundary at the left and right side,which are restricted by horizontal sliding support, and the boundary of the underlying bedrock is restricted by a fixed support. The frictional contact unit is introduced between the boundaries of the formation interface to imitate the slipping effect of the interface. Under different interfaces, a comparison between the conventional response displacement method and the generalized response displacement method for shallow-buried DOT shield tunnels shows that: 1) the generalized response displacement method with the assumption of interface slippage can reflect the seis? mic effects of the DOT shield tunnel more accurately; 2) under the seismic force displacement, the additional bending moment of the segment lining distributes in an inclined number 8, and the additional bending moment of the center pillar is linear with the inflection point near the midpoint; 3) the additional axial force on the segment is basically pressure, and the additional axial force on the center pillar is one of tension with an unchanged value along the height; and 4) the additional shear force on the segment distributes as a number 8 and the additional shear force on the center pillar remains unchanged along the height.
Abstract:
The basic principles, analytical method and problems regarding the conventional response displacement method are described. The formulas of formation spring stiffness are given with the assumption of both a slip and noslip contact surface, and a generalized response displacement method is put forward based on the formation-structure model. As for this method, the seismic force displacement is applied on the boundary at the left and right side,which are restricted by horizontal sliding support, and the boundary of the underlying bedrock is restricted by a fixed support. The frictional contact unit is introduced between the boundaries of the formation interface to imitate the slipping effect of the interface. Under different interfaces, a comparison between the conventional response displacement method and the generalized response displacement method for shallow-buried DOT shield tunnels shows that: 1) the generalized response displacement method with the assumption of interface slippage can reflect the seis? mic effects of the DOT shield tunnel more accurately; 2) under the seismic force displacement, the additional bending moment of the segment lining distributes in an inclined number 8, and the additional bending moment of the center pillar is linear with the inflection point near the midpoint; 3) the additional axial force on the segment is basically pressure, and the additional axial force on the center pillar is one of tension with an unchanged value along the height; and 4) the additional shear force on the segment distributes as a number 8 and the additional shear force on the center pillar remains unchanged along the height.
.Application and Comparison of Conventional and Generalized Response Displacement Methods for Shallow-Buried DOT Shield Tunnels[J] MODERN TUNNELLING TECHNOLOGY, 2017,V54(4): 83-90