【作者】 朱维申； 李勇； 王汉鹏； 李术才； 张强勇；

【Author】 ZHU Wei-shen LI Yong WANG Han-peng LI Shu-cai ZHANG Qiang-yong (Geotechnical and Structural Engineering Research Center Shandong University,Jinan 250061,China)

【机构】 山东大学 岩土与结构工程研究中心；

【摘要】 分岔式隧道是一种新型的隧道工程结构形式,它分为四个工程段：分离段、小间距段、连拱段和大拱段。为了研究这种隧道施工过程中的稳定性,采用通用的分析软件 FLAC3D 来研究。从施工过程来看,分岔式隧道的大拱段到连拱段的稳定性问题最令人关注,也是最难施工的部位,因此重点对此部位进行数值模拟。研究表明：由于围岩较好,开挖后整体稳定性较好,大拱段压应力主要集中在隧道的拱脚；拱顶和底板处产生拉应力；连拱段压应力主要集中在隧道的中隔墙部位,拱顶和底板处产生拉应力；位移以垂直向为主,支护后不超过2mm；塑性区较少,且主要分布在连拱段的中隔墙部位,因此要重点加固此部位,同时, 用三维地质力学模型试验进一步研究了其施工过程的稳定性,与数值模拟结果一致。更多还原

【Abstract】 The branching-out tunnel is a special underground structure,which contains four types of structure sections:a section of separated structure,a section of small-spaced structure,a multi-arched structure and a large-span structure.In order to study the stability of the branching-out tunnel construction process,we use universal simulation analysis software FLAC3D to study the whole construction process.The construction process from the large-span structure to the multi-arched structure is difficultly constructed,which is significantly simulated by FLAC3D numerical model.The whole stability is good because of good wall rock,the stresses focus on the feet of the large-span structure and the middle wall of the multi-arched structure,and the tensions focus on roof and floor;the vertical displacement is main displacement and max displacement is about 5mm with no support and 2mm with support; numerical plastic zone is less and distributes on middle wall.In the meantime,we also use 3D geo-mechanical model test to study the problem,and the results are consistent with those of numerical simulation.更多还原