复杂条件下隧道支护体时效可靠性探讨  

Time-reliability of tunnel support under complex conditions

作　　者：贾剑青[1] 王宏图[1] 李晓红[1] 牛惠民[2] 胡国忠[1] 

机构地区：[1]重庆大学西南资源开发及环境灾害控制工程教育部重点实验室,重庆400044 [2]兰州交通大学交通运输学院,甘肃兰州730030

出　　处：《岩土工程学报》2008年第3期390-393,共4页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金资助项目(50334060,50474025,50774106);国家重点基础研究发展规划(973)项目(2005CB221502);国家自然科学创新群体基金(50621403);重庆市自然科学基金资助项目(CSTC,2006BB7147,2006AA7002);兰州交通大学自选课题资助项目(40723)

摘　　要：以Kelvin-Voigt黏弹性模型作为大埋深隧道支护体流变模型,推导了隧道支护体的位移时效方程;提出了支护体时效可靠性的定义,即支护体时效位移曲线(Ur(ti))与位移阀值的交点(A点)到位移收敛值间弧段长(AB)与围岩与支护体发生作用点(O点)与位移收敛点(B点)之间弧段(OB)长的比值,即就是pf=AB/OB。在此基础上,运用自编程序计算了若干工程实例。工程实例表明:支护体的破坏概率与支护体弹性模量(E2)、围岩弹性模量(E1)以及支护厚度比较敏感;随着围岩弹性模量的降低,相同支护强度的支护体破坏率越小。The Kelvin-Voigt model was taken as the rhelogical model of large deep tunnel support,and the displacement time-equations of tunnel support were derived.The time-reliability of the tunnel support was defined,i.e.,the ratio of the length of the arc AB and OB.The length of AB was the distance between the intersection A,which was the displacement time–curve（U r（t i）） and the special value of displacement,and the displacement converging valve.The length of OB referred to the distance between the action position O of surrounding rock and the support and the converging valve of displacement.On such a basis,some real projects were calculated using computer programs.The results show that the failure probability of the tunnel support is very sensitive to the elastic modulus of surrounding rock and the tunnel support,and it is also sensitive to the supporting height.The failure probability of the tunnel support with the same supporting strength will reduce when the elasticity of surrounding rocks reduces.

关 键 词：隧道 支护体 时效可靠性 Kelvin-Voigt模型 

分 类 号：U45[建筑科学—桥梁与隧道工程]