THM modeling of ground subsidence induced by excavation of subway tunnel

In order to solve the problem of ground traffic congestion, many cities in China (such as Beijing) have constructed or are being building up underground subway transportation networks. The ground settlement or even collapse induced by the excavation of subway tunnels is a crucial issue that directly relates to the safety of the citizens and buildings. The ground subsidence is dependent on the stability of the geotechnical media around the subway tunnels, which is controlled by the thermal (T), hydraulic (H) and mechanical (M) factors and the THM couplings. Therefore, it is essential to analyze the coupled THM effects on the ground subsidence induced by tunneling. A THM coupled model is developed to investigate the ground subsidence induced by the tunnel excavation, and then the outcomes simulated by this model are compared with that obtained from physical simulation experiments. A good agreement is found between the modeling results and measured data, indicating that the developed model is provided with well predicting capability to describe the tunneling induced ground subsidence under the coupled THM effects.