Study On Land Subsidence Caused By Section Of Sanyuanqiao～Liangmaqiao Station On Beijing Metro Line 10 Running Through Existent Buildings

Shield tunneling, an important construction method in Metro engineering in China, is widely applied in underground engineering due to its proper advantage of intelligentized, safe and prompt. However, the shield tunneling is prone to arouse land subsidence and distortion, which will have severe influence on economic and social development. Especially the excessive land subsidence will endanger the safety of surrounding buildings and underground tubes.This thesis aims at the case project of 10th Line of Beijing Metro, which runs between Sanyuaqiao and Liangmaqiao and also drill through the NO.8th residential building. By analyzing the substantive field observation data, the effect that shield digging has on horizontal and vertical land subsidence has been studied. Besides, the percentage of subsidence in each phase of shield digging as well as its incidence to horizontal land subsidence has been discussed.Physical dynamic model of shield tunneling has been established by FLAC^3D. On the basis of simulating its impact on the existent buildings when running through them, the influencing regulation has been studied. What's more, the calculated land subsidence in the designated cross-section by numeric modeling basically fit with the actual value, which speaks volumes for that if only the sound model has been set up as well as adopting rational parameter, numeric modeling will be an effective method in studying shield construction.Through analyzing field observation and numeric modeling, and take the impact on soil caused by practical engineering parameter into consideration, safe construction measurements have been proposed to reduce the fatalness of walking by buildings, and hopes to help the field construction effectively.