Deformation Of The Existing Elevated Lines Of Urban Rail Transit Induced By Shield Tunneling And The Deformation Control

Along with the abundant construction of urban rail transit network and other municipal engineering, new built tunnels crossing the existing elevated lines of urban rail transit are on the increase. The crossing is certain to induce deformation of ground, bridge and track structure, which, if excessive, would affect the normal operation and safety of the existing elevated lines of urban rail transit.Based on the engineering case of culvert tunnel of Beijing section of the South-North Water Diversion Project crossing Qinghe Bridge of Beijing metro Line 13, this paper has made an overall analytical study on deformation of ground and the existing elevated lines which is induced by shield tunneling and the deformation control through analysis of monitoring data and numerical simulation. The main works and result are listed as follows:1. This paper analyzes the reason and mechanism of deformation of ground and the existing elevated lines induced by shield tunneling.2. Based on monitoring data of the case, this paper carefully studies deformation of surface, bridge and track structure caused by shield tunneling from space and time, get the regulation and relation of their deformation, and analyze the reason of the deformation.3. A numerical test model with ANSYS is built to simulate the construct of shield tunneling, and the validity of this model is verified by comparison of numerical test results and monitoring data. Control effect of shield tunnel construction management and protection for the existing lines, such as control soil pressure, grouting parameters, the distance between partition wall and shield tunnel and the material of partition wall, on deformation of ground and existing lines, has been studied.4. Analyzing in theory and by monitoring works, and simulating with numeric model, combine with summarizing the control measures of crossing engineering, the Process and measures of the control on deformation of ground and the existing elevated lines which is induced by shield tunneling have been brought forward.