| Tunneling will inevitably result in a loss of ground due to soil deformation and displacement into the opening. The tunneling-induced soil movement and deformation may do damage to the pre-existing structures and underground utilities. It is necessary to predict the ground surface movements and their influence to adjacent utilities so that precautious measures can be taken to protect these utilities from tunneling. A FLAC computational model is established in according to the characteristics of tunneling, and elastic-plastic method is used to research into the influence of the tunneling on ground movement and underground utilities, and the main content of this paper as follows:1. Simulation analysis of construction of the Dongzhimen subway station of Beijing Capital Airport line, research subsidence controlling and construction scheme optimizing of cutting across and underpassing an existing subway tunnel under complex environmental conditions.2. In order to determine the maximum ground settlement at the earth's surface according to the safety requirement of pipelines ,analyse the effect on underground pipelines on the ground caused by tunnel work, find out the relation between the maximum ground settlement at the earth's surface and the deflection and strain of pipelines.3. Influencing factors of tunneling on adjacent underground utilities are analyzed, which mainly include the relative position of pipelines and tunnel, ground lose, buried depth of pipelines, tubes and so on. All of these are based on the simulation analysis of the shallow tunnel of Dongzhimen subway station of Beijing Capital Airport line.4. Count the deformation and stress of pipelines induced by tunnel work rely on the widely used theory, and compare the result with result of numerical simulation analysis in order to find rational method to predict and estimate the effect on pipelines. Security discrimination method and protective measures of underground utilities are generalized.
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