不同应力场下软弱围岩公路隧道的力学特征试验  

Mechanical Characteristic Tests of Soft-weak Surrounding Rock Highway Tunnel Under Different Stress Fields

作　　者：来弘鹏[1] 林永贵[2] 谢永利[1] 杨晓华[1] 

机构地区：[1]长安大学桥梁与隧道陕西省重点实验室,陕西西安710064 [2]广州市市政工程设计研究院,广东广州510060

出　　处：《中国公路学报》2008年第4期81-87,共7页China Journal of Highway and Transport

基　　金：国家西部交通建设科技项目(200131800021)

摘　　要：运用自行研制的用于地质力学模型试验的隧道开挖工具,系统地开展了基于先加载后开洞思路的不同应力场公路隧道模型试验,研究了开挖对不同应力场公路隧道围岩应力分布的影响,分析了不同初始应力场公路隧道结构的受力特点。试验结果表明:隧道开挖后,不同应力场洞周各部位径向压力松弛程度不同;施作衬砌之后,不同应力场洞周各部位径向压力回升程度也不同;除在拱顶、拱底方向围岩与衬砌接触压力随着侧压力系数的增大而略有减小外,其他各方向均随侧压力系数的增大而增大,且影响较明显;应力场对衬砌结构切向应力影响也很大。According to different stress fields, lots of highway tunnel model tests which were used to study the influence of excavation on the stress distribution of surrounding rocks and analyze mechanical characteristic of highway tunnel structure under different initial stress fields were taken systemically by the test flat and excavation apparatus for the first time. The test result shows that after tunnel excavation, the radial stress relaxation degree of each site around the tunnel under different stress fields is different; after making the lining, the radial pressure of each site around the tunnel rises to different degrees under different stress fields; the surrounding rock and lining contact pressure slightly decreases with the increase of lateral pressure coefficient in the vault and the intrados direction and increases with the increase of lateral pressure coefficient at all the other directions and the influence is also quite noticeable; the stress field has a great impact on tangential stress of lining structure.

关 键 词：隧道工程 软弱围岩 模型试验 力学特征 应力场 衬砌结构 

分 类 号：U459.2[建筑科学—桥梁与隧道工程]