Study On The Disturbance Effect And Control Technology About The Large Diameter EPB Shield Passing Beneath Xiangjiang River

There are more and more problems of disturbance effects of underwater tunnel with shield as the strong development of urban rail transit. The lack of study on underwater shield tunnel disturbance effects and the immaturity of construction control technology caused a lot of huge losses. Combined with the topic of the Ministry of Railways "Study on Key Construction Technique of Underwater Railway Tunnel with Large Diameter Shield "(2011G013-C), the disturbance effects of large-diameter earth pressure balance shield across the Xiangjiang River dams with two methods, theoretical empirical formula and numerical simulation of fluid-structure interaction analysis were made in this disseration. On the base of numerical analysis results, the stability of the shield tunnel excavation face in overpressure and under voltage state was calculated. According to theoretical calculations, numerical simulation and field data to improve the construction control technology was made in this dissertation. The main contents of this paper include as follows:(1) The process of two holes of the large diameter EPB shield successively excavate beneath Xiangjiang river to east levee had been numerical simulated based on fluid-solid coupling analysis model. With the simulation results of various stages of the shield tunnel construction, disturbance effects caused by two holes successively excavating had been compared and analyzed.(2) Consideration of monitoring data, surface settlement near the single or double shield tunnel excavation surface prediction formula was derived based on Peck formula and duration curve. With gray relational analysis the order of effect size of7factors in construction of the surface settlement was established.(3) Disturbance effects of the surrounding soil when shield tunnel across the Xiangjiang River dams first and second time in overpressure and undervoltage condition were compared and analyzed. Disturbance superposition effects caused by two passes of the shield had been taken into account. With MATLAB process the data, three-dimensional surfaces were sketched.(4) Combined with Xiangjiang River tunnel engineering of the inter-city railway, the accuracy of the engineering geological exploration, excavation face pressure control technology and the synchronous grouting and secondary grouting control technology were for forward.