Abstract:

The impact of excavation of shallowburied tunnels on the surrounding environment is worthy of attention. On basis of the deformations of the ground surface caused by the driving of Wulong tunnel underneath the foundations of buildings in Chongqing, simplified plane strain model is adopted and numerical simulation and analysis are made for the construction of the tunnel by two different calculation methods. The aim of the study is to analyze the impact of different excavation methods of soft tunnels on the ground deformations and forcebearing conditions of the surrounding rock mass. The calculation results of two different construction conditions, i.e., the construction condition with reinforcement and that without reinforcement, are compared. The comparison results show that if such measures as heavy reinforcement, short advance rate and consolidation of critical positions are taken for shallowburied tunnels, the impact of the excavation of the tunnel on the surrounding environment can be effectively reduced.

Key words: soft rock, shallowburied tunnelground deformationforcebearing of surrounding rock massnumerical simulation