基于台阶法的小净距隧道施工变形规律研究

RESEARCH ON THE DEFORMATION LAW OF SMALL CLEAR DISTANCE TUNNEL CONSTRUCTION BASED ONSTEP METHOD

为降低小净距隧道施工成本,缩短施工工期,文中以威海某小净距隧道施工为背景,利用现场实测与数值模拟手段相结合的方式,对小净距隧道动态开挖过程中的围岩变形规律进行分析,得出台阶法施工隧道地表沉降及拱顶沉降变形规律,根据围岩塑性区,得到隧道施工薄弱区域,为隧道安全施工提供参考。

The construction of a small net distance tunnel in Weihai is taken to study the methods for reducing the construction cost and shorten the construction period of a small net distance tunnel,in which a combination method of on-site measurement and numerical simulation is proposed to analyze the deformation law of the surrounding rock during the dynamic excavation process of the small net distance tunnel.The deformation law of the surface settle-ment and arch settlement of the tunnel constructed by the step method is obtained.Basing on the plastic zone of the surrounding rock,reinforcement measures for the surrounding rock of the step method construction tunnel are pro-posed,providing the guidance for safe tunnel construction.