Tunnel Excavation Research On Surrounding Rock Stability And Surrounding Water Resources Impact

In recent years, with the fast development of our economy, large numbers of infrastructures have been constructed in our country, in which the projects of tunnels are essential. Rock body is made up of rock which has special structure and it is related to certain geological and physical environment. When excavating in such geological parts , its original state of balance is destroyed , which in turns will lead to a series of severe chain reaction and disaster of collapses. If the collapses of surrounding rock could not be effectively prevented, the direct economic loss would be enormous, between two and three million. In addition, the equipment and personnel casualty would always appear. Even the schedule of the construction would be delayed. All these consequences cannot be underestimated. Therefore, how to ensure the stability of surrounding rock becomes the most impending pivotal technical problem.Through the methods of theoretical analysis and numerical simulation, this paper discusses the stress characteristic of surrounding rock and analyzes the reasonable construction methods under specific conditions, based on the practical tunnel work of Xing-fen Expressway. By way of establishing the tunnel construction numerical model, the numerical simulation is operated under the specific construction conditions of different scales of surrounding rock and ground water, in two kinds of excavation methods. The stability of the surrounding rock can be calculated via the analysis of the stress characteristic of special parts of tunnels(such as the top and the side walls ) , the strain characteristic, the displacement of the surrounding rock and the stress characteristic of the supporting structure. This study is intended to provide effective foundation for practical projects.