雪峰山隧道原岩应力场和开挖二次应力场特征分析  

Analysis of initial rock stress field and secondary rock stress field of Xuefengshan tunnel

作　　者：黄戡[1,2] 彭建国[2] 刘宝琛[1] 丁国华[2] 王跃飞[2] 马德青[2] 

机构地区：[1]中南大学土木建筑学院,湖南长沙410075 [2]湖南省交通规划勘察设计院,湖南长沙410008

出　　处：《中南大学学报（自然科学版）》2011年第5期1454-1460,共7页Journal of Central South University:Science and Technology

基　　金：西部交通建设科技项目(20033179802);国家博士后科学基金资助项目(20090461021)

摘　　要：为了解雪峰山隧道原岩应力场和隧道开挖后围岩的二次应力场分布特点,应用有限元软件建立仿真模型,模拟河谷下蚀和隧道开挖过程。为了验证数值模型的可靠性,对比分析相应位置的现场测试应力和数值模拟应力,并以现场应力测试值对应力边界的应力进行反演分析。研究结果表明:应力数值模拟值和现场测试值较接近,说明所建模型可靠;隧道轴线剖面主应力可分为应力平稳带和浅表生改造影响带;在应力平稳带的硬、软相间部位或断层带附近出现应力分异现象;浅表生改造影响带通常为应力降低区,地形明显变化处可造成应力局部增高;隧道周边的最大主应力出现应力集中;随着与隧道周边的距离增加,最大主应力很快降低;隧道周边未出现拉应力,开挖影响范围为地表至1倍洞径之间。To understand initial rock stress field and secondary rock stress field due to excavation in Xuefengshan tunnel, finite element software was used to establish numerical model to simulate the valley incision and tunneling process. In order to verify the reliability of the numerical model, comparison of stress numerical values and monitoring values in field tests was conducted, and the stress boundary was done. The results show that the model is reliable because numerical simulation stress is close to that of the field test. The spread of stress can be divided into two bands, i.e., the equable stress band and the effected band of epigentic-surface reformation. Around fracture in the equable stress band, there are stress varied phenomena and local high stress bands in the effected band, especially at the position of apparent landform chance. Stress concentration is serious around the tunnel. With the increase of the distance from the tunnel, the maximum principal stress decreases rapidly. Tensile stress does not appear around the tunnel, and the excavation influence band is from 0 to 1 times of the hole diameter.

关 键 词：隧道工程 原岩应力 二次应力场 

分 类 号：U459.2[建筑科学—桥梁与隧道工程]