水工隧洞砂岩段围岩环形开挖预留核心土法受力分析  

Stress analysis with reservation core soil of annular excavation on wall rock in sandstone section of hydraulic tunnel

作　　者：杨燕伟[1] 王红雨[1] 路瑞利[1] 

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021

出　　处：《宁夏工程技术》2009年第4期388-391,共4页Ningxia Engineering Technology

基　　金：教育部科学技术研究重点项目(207126)

摘　　要：宁夏沙坡头水利枢纽北干渠输水隧洞砂岩段属V类围岩,岩体自稳时间短,自稳程度差,因此需要通过数值模拟对隧洞施工方法进行分析.设计采用环形开挖预留核心土法进行开挖支护施工.利用ANSYS有限元软件,采用Druck-Prager弹塑性模型对隧洞分部开挖支护施工过程进行模拟,分析了施工各阶段的应力和变形情况,从拱顶位移、应力分析和塑性区分布来看,砂岩段采用环形开挖预留核心土法施工是可行的.为保证掌子面稳定,建议在施工过程中,对预留土体进行加固.The wall rock of sandstone section belongs to category V and the reservation core soil of annular excavation is applied in the tunnel project of northern main channel of Shapotou hydro-junction in Ningxia. Due to the reason that rock is liable to distort for its shorter stability time and poor self-stabilization, so it is necessary to analyze tunnel construction with numerical simulation method. Using FEM software ANSYS, the construction process is simulated with Druck-Prager elasticplastic model in this paper. The stress and distortion of rock in every construction stage are analyzed. The results show that the displacement of arch top,stress and distribution of plastic on walk rock are reasonable by calculation using reservation core soil of annular excavation. In order to ensure stability of the tunnel face, reinforcing core soil is proposed in the construction.

关 键 词：水工隧洞 砂岩 有限元 数值模拟 

分 类 号：TV672.1[水利工程—水利水电工程]