盾构隧道立交穿越铁路枢纽车场咽喉区及市政桥涵防护方案技术研究

Research on Protection Scheme of Shield Tunnel Overcrossing Throat Area of Railway Junction and Municipal Frame Structure

铁路枢纽咽喉区布置复杂、变形控制严格,盾构隧道穿越该类工程时,确保铁路运营及隧道施工的安全意义重大。本文以某地铁盾构隧道穿越铁路枢纽咽喉区及市政桥涵工程为依托,提出了对枢纽车场采取“板凳结构”和隔离注浆的预加固方案。通过对有、无加固措施工况下穿越工程的模拟分析,对比发现,在采取加固措施后,盾构施工过程引起的轨道变形可满足轨道不平顺指标管理值要求,且市政桥涵沉降明显减小,最大沉降量减小约57.7%,证实了本工程加固措施是必要且有效的。

It is of great significance to ensure the safety of railway operation and tunnel construction when shield tunnel passes through the complex layout and strict deformation control of the throat area of railway junction. Based on a shield tunnel passing through the throat area of railway junction and municipal frame structure project, the paper puts forward a scheme of pre-strengthening measures of “bench structure” and isolated grouting for railway junction. Through the simulation analysis of the crossing project with and without reinforcement measures, it was found that after the reinforcement measures, the track deformation caused by shield construction could meet the management requirements of the track irregularity index, and the settlement of municipal frame structure is reduced significantly, and the maximum reduction of settlement is about 57.7%, which confirms that the reinforcement measures of the project are necessary and effective.