Analysis of Initial Stress-Strain State’s Influence on the Collapse of Tunnels

Numerical simulations of rock-buried tunnel collapse under plane pulse loads propagated from ground were performed using the nonlinear FEM software of LS-DYNA, the difference of structure collapse between the cases with initial stress-strain conditions being concerned and not concerned was observed. The calculations indicate that, provided other conditions are equal, when initial state is taken into account the collapse is more serious than that regardless of initial conditions. Initial stress-strain state has much influence on the underground structure’s dynamic response, hence the initial conditions should not be ignored when doing dynamic analysis of underground structures.