隧洞进出口顶拱悬吊锚筋桩受力特征研究  

Stress Characteristics of Suspensor Anchor-stake for Reinforcement of Tunnel Crown at the Import Section

作　　者：周家文[1] 刘兴宁[2] 李洪涛[1] 周宏伟[1] 徐富刚[1] 

机构地区：[1]四川大学水力学与山区河流开发保护国家重点试验室,四川成都610065 [2]中水顾问集团昆明勘测设计研究院,云南昆明650051

出　　处：《应用基础与工程科学学报》2012年第6期994-1005,共12页Journal of Basic Science and Engineering

基　　金：国家自然科学青年基金资助项目(41102194);中国博士后科学基金资助项目(20110491741)

摘　　要：悬吊锚筋桩是隧洞进出口顶拱加固的一种特殊方式,其受力特征对加固方案的设计有重要指导作用.首先,对悬吊锚筋桩的数值计算原理进行分析并给出了一简单算例,分析表明:灌浆环的合理模拟与否对计算结果影响很大.随着灌浆环周长和内摩擦角的增大,悬吊锚筋桩的受力不断增大;悬吊锚筋桩间排距越小,加固效果越明显.然后,对糯扎渡水电站2#导流隧洞进口的开挖支护进行三维数值模拟分析,计算结果表明:悬吊锚筋桩的受力随着分段开挖的进行而不断增大,随着分层开挖的进行受到其它支护措施的影响比较明显.悬吊锚筋桩受力沿隧洞轴向先增大后减小;沿中轴面对称分布,且最大受力位于中轴线附近.Suspensor anchor-stake is a special method used for reinforcement of tunnel crown at the import section, the mechanical characteristics of suspensor anchor-stake is very important for the design of reinforcement measures. Firstly, the numerical simulation theory of suspensor anchor- stake is analyses with a simple numerical simulation example, the accuracy of compute results is influenced by the accurate simulated of the grout. The stress of suspensor anchor-stake is increased along with the increase of perimeter and friction angle of grout, and if the spacing and row distance are littler, the reinforcement effect of suspensor anchor-stake is more distinctness. Then, three-dimensional numerical simulation of the excavation and support of the inlet in No. 2 diversion tunnel located at Nuozhadu Hydropower station was carried out. Compute results showed that, the stress of suspensor anchor-stake was increased along with the subsection excavation, and influenced by other support measures obviously along with the layer excavation. The stress of suspensor anchor-stake was first increasing and then decreasing along the axial direction,and symmetry distributed along the axial plane, the maximum stress was close to the axial position.

关 键 词：隧洞 支护措施 悬吊锚筋桩 受力特性 数值模拟 

分 类 号：O319.56[理学—一般力学与力学基础]