Analysis Of Surface Subsidence Of Metro Tunneling With 'PBA' Drift-Pile Method

Recently, with the development of urban underground space, especially the implementation of the big underground construction such as subway network and underground complex and so on, the 'PBA' Drift-Pile Method is more and more used popularly by people for the unique dominance of its construction way in shallow buried underground excavated tunnels. For studying the method deeply, it is essential to study the law of surface subsidence.In this paper, the law of the monitoring data of the method in the construction phase will be studied detailedly, and use finite element simulation software called MIDAS to calculate, then analyse the difference between the calculated results and the monitoring data. At the same time, study the influencing factors of surface subsidence, dome subsidence and convergence respectively then sum up the law and some problems which should be paid attention to in this method.1,Using numerical simulation method supplemented by analyzing the law of monitoring data , study the law of surface subsidence in the phase of excavated guiding hole and the phase of buckling main arch and excavating the soil.2,Compare the characters of surface subsidence of different sections of the span in the phase of excavated guiding hole and the phase of buckling main arch and excavating the soil, and some issues should be noted in the construction.3,The use of numerical simulation software MIDAS-GTS realizes the manifestation of construction Step-by-step sequence in one model like the real construction.