大跨度土质隧道自然成拱优化数值模拟研究  

Research on simulation and optimization of large-span soil tunnel under natural arching rail

作　　者：蒋凌云[1] 陈秋南[1,2] 李腾飞[1] 赵磊军 刘文骏[1] 

机构地区：[1]湖南科技大学土木工程学院,湖南湘潭411201 [2]湖南省普通高校土木工程施工过程与质量安全控制重点实验室,湖南湘潭411201

出　　处：《湖南文理学院学报（自然科学版）》2014年第4期43-47,共5页Journal of Hunan University of Arts and Science(Science and Technology)

基　　金：国家自然科学基金项目(41172275;41372303);湖南省交通厅科技进步与创新项目(201229)

摘　　要：土质隧道围岩在工程实际施工中具有明显的弹塑性变形特征.通过运用FLAC3D软件,模拟隧道实际开挖过程,可得到隧道开挖过程中围岩应力分布及周边位移变化量,为隧道的施工提供预警信息和优化隧道设计提供理论支持.在控制地表变形方面,采用交叉中隔壁法(Cross diaphragm-CRD)施工时,地表最大沉降量为20.37 mm,而双侧壁导坑法则为25.8 mm,结果表明CRD法在控制围岩变形方面要优于双侧壁导坑法.因此,为了避免隧道在开挖过程中发生塌方等事故,应优先采用CRD法开挖.然而,运用FLAC3D软件模拟CRD法开挖过程,得到开挖隧道上部导洞所引起地表的沉降量占总沉降量的50%以上.因此,对CRD法上部导洞的开挖工序进行优化,能有效地降低塌方等事故发生的概率.During the process of using FLAC3D numerical simulation of the actual tunnel excavate process, it can be drawn rock stress distribution, surrounding the amount of displacement, for the tunnel construction to provide warning information and guidance, the theoretical support is provided to optimize the tunnel design. In the aspect of control surface deformation, the method of CRD maximum settlement amount is 20.37 mm when using CRD（Cross diaphragm） method to construct, while the method of double side is 25.8 mm, the result illustrate CRD method is superior to double side drift method in the aspect of control rock deformation. Therefore, in order to avoid the tunnel landslides and other accidents during excavation, CRD method should be considered preferentially than double side drift method. The process of using FLAC3D software to simulate CRD method excavation, the upper guide hole excavated tunnel surface subsidence is more than 50%of the total settlement amount. So it can effectively reduce the probability of collapse and other accidents by optimizing the excavation process of CRD method upper guide hole.

关 键 词：优化数值模拟 改变工序后的CRD法 自然成拱 土质隧道 

分 类 号：U45[建筑科学—桥梁与隧道工程]