随着城市地铁不断发展，大型换乘枢纽建设开发利用地下空间问题逐渐增多,地铁穿越既有地下建（构）筑物的情况时有发生，如何最大化的优化施工设计，确保工程质量，保证既有建（构）筑物的运营安全，已成为地铁建设中亟待解决的重要问题。 　　　本课题以某地铁车站换乘通道接建既有地下商场工程为依托，通过理论分析，选取合理的施工方法，并借助MIDAS GTS数值模拟软件和现场的监测数据，分析研究了换乘通道接建施工时围岩的变形规律。结果表明浅埋暗挖法接建既有地下商场是可行的，大管棚超前支护及注浆加固地层有效的，较好的控制了围岩的变形及既有地下商场的沉降。 　　　针对工程的具体情况，本文通过模拟计算，分析了在不同的施工参数下换乘通道开挖对地层及既有地下商场的沉降影响，比较结果，得出较为优化的施工参数，为类似的工程提供相应的参考。研究表明：换乘通道合理的台阶开挖长度为4.5m（0.75）；合理的管棚直径为φ108mm，管长20m；合理的注浆加固范围为3.0m。

With the development of urban subway, developing and using the underground space problems gradually increased when construct the large transfer hub,situations of subway crossing the existing underground construction(structures) occurred many times.How to optimize the construction design in the best way,ensure the project quality and the operational safety of existing buildings (structures),this has become an important issue to be solved in the subway construction. 　　　The topic based on a subway station transfer channel connected with the existing underground mall,by theoretical analysis, selecting appropriate construction methods, with the MIDAS GTS simulation software and on-site monitoring data to analysis the surrounding rock deformation of the transfer channel construction.The result shows that the shallow excavation method is feasible to connected with the existing underground mall,Forepoling pipe roof and grouting reinforced strata is effectively,better control of the surrounding rock deformation and the existing underground mall settlement. 　　　For the specific situation of the project, the paper calculated by simulating,analyzed settlement affect to the existing underground mall when the transfer channel excavation under different construction parameters. Compare the results and obtained the more optimized construction parameters, provide reference for similar projects.Study shows that the reasonable steps excavated length of transfer channel is 4.5m（0.75D）;the reasonable diameter of pipe roof is φ108mm,the tube length is 20m;the reasonable range of grouting reinforcement is 3.0m.