Analysis Of Surface Subsidence Caused By The Tunnrling Method Of Ultra-shallow Tunnel

With the development of economy, increase the development and utilization of underground space has become an important way to solve the problem of lack of space in the process of urban development. At present, the main forms of the use of urban underground space are urban subway and underground channel. Because the city underground projects often in densely populated urban downtown area, at the same time to consider issues such as quality of the project, to consider the reduction of cite construction on the influence of existing order.Safely and effectively support in advance, initial support and the second support should be taken in the construction to control ground settlement., also should have a corresponding method to predict surface settlement, in order to control and take measures, the surface subsidence controlled within an acceptable range, in order to ensure safety construction. With lots of documents and information inquiries, found that the Peck formula and some other commonly used type of surface subsidence experience formula are against the deep depth in the city subway, and the surface subsidence of shallow underground passage of law research is relatively less. Combined whit the engineering practice, the Peck formula and some other surface subsidence prediction experience formula is not apply for the argument in shallow underground engineering yet.By combined with the three underground passageway construction engineering on the Yangtze River Road in Hefei examples, a brief introduce of the Construction Method of shallow depth excavation based on the brief introduction, the grey theory established from the time of the GM(1,1) model, measured a large number of engineering and fitting data, it is concluded that the similar project construction, only consider the time process of surface subsidence rule forecasting formula. And through multiple data is verified.Modeling by the three-dimensional Lagrange analysis software FLAC3D obtained tunneling method in the construction of the C channel of Sipai-building underground, obtained the displacement contours and stress cloud, and got some records of the settlement for the whole construction process at the surface of the ground, and use these data to verify the empirical formula, demonstrates the empirical formula for the applicability of the theoretical.At the end of the paper, summarizes the shallow depth excavation of surface subsidence rule formula and FLAC simulation. And points out that the innovation of this paper and the direction to continue to research and work towards.