小间距群洞施工影响效应方案优化研究

结合北京地铁四号线宣武门站工程对小间距群洞施工的影响。通过正交试验和数值模拟2种方法对群洞的施工工法、开挖顺序、各导洞开挖面之间的距离以及台阶长度4个主要因素进行优化，并就群洞施工对地表最大沉降和群洞间相互影响进行分析。通过这些研究分析，确立合理的施工方案，为以后的研究提供参考。

Optimization of Construction Scheme of Group Tunnels with Small Spacing

Taking the construction of the small spaced group tunnels of Xuanwumen Station on No. 4 Line of Beijing Metro as an example, the author optimizes the construction methods, excavation sequences, distances among excavation faces of the pilot tunnels and bench lengths by orthogonal tests and numerical simulations. The author also analyzes the ground surface settlement caused by construction of group tunnels, as well as the mutual influence among the group tunnels. Reasonable construction scheme is determined on basis of the analysis and study results. The paper can provide reference for future studies.