西安城墙在地铁建设与运营中的保护措施分析

Study on the Protection of Xi'an City Wall during the Construction and Operation of Xi'an Metro

西安地铁已建和在建的地铁线路多次穿越西安城墙及护城河,如何保证古城墙在地铁建设和运营期间的安全成为较为突出的问题。结合城墙的自身结构问题与工程地质情况的特殊性,通过对比分析相关工程资料和文献,指出:施工阶段,双线分离规划线路是盾构安全下穿城墙的重要前提,合理的土仓压力和注浆参数加之连续施工是盾构安全下穿最主要的主动防范措施,城墙地基土层注浆加固加之门洞钢架支护是盾构安全下穿必要的被动防范措施;运营阶段,采用钢弹簧浮置板道床可以明显减小地铁列车穿越城墙时引起的振动,保证地铁运营期间古城墙的安全。

Hot to maintain the ancient city wall is a burning issue during the time when the existing and new metro lines of Xi＇an are passing under the city wall and city moat. Based on the particularities of the city wall structure and engineering geology, relevant engineering data and literature are compared and analyzed. The results show that, in construction stage, separated double line is an important prerequisite for shield tunnel passing under city wall safely. Reasonable earth pressure and grouting parameters and continuous construction are the main active preventive measures, and foundation soil grouting reinforcement and door steel frame supporting are the necessary passive preventive measures for safe construction. Using steel spring floating slab track can significantly reduce the vibration caused by subway train passing nnder the wall to maintain the ancient city wall during metro operation.