Influence of high geo-stress on dynamic response analysis of mountain tunnels

The safety of mountain tunnels located in regions of high seismic intensity in recent earthquakes has been questioned. To sufficiently analyze the influence of high geo-stress conditions on tunnels under earthquake excitation, a series of numerical models corresponding to each condition were built based on a western tunnel project. Considering the uncertainty of the geo-stress value due to inevitable error of sampling, several work conditions corresponding to each value were computed and compared. Sensitivity analyses indicate that the horizontal geo-stresses cause shear action on the tunnel linear. If the lateral pressure coefficient of geo-stress exceeds a certain value, the tunnel linear possibly will be damaged. In addition, a geo-stress impact factor was proposed to reflect the influence of geo-stress on the dynamic response of mountain tunnel. It is found that effect of geo-stress plays an important role in the deep-buried tunnels than in shallow-buried tunnels. © 2016 ejge.