隧道开挖中的应力旋转和裂隙塑性变形问题研究  

Research on Stress Rotation and Plastic Deformation of Cracks in Tunnel during Excavation

作　　者：孙常新[1,2] 韩立新[1] 高峰[2] 

机构地区：[1]华北水利水电学院,郑州450011 [2]重庆交通大学,重庆400074

出　　处：《现代隧道技术》2011年第1期6-11,共6页Modern Tunnelling Technology

基　　金：华北水院2009年度青年科研基金项目(HSQJ2009013);国家自然科学基金资助项目(50678077);重庆市自然科学基金项目(CSTC;2008BB6066);重庆市教委科学技术研究项目(KJ090403)

摘　　要：通过对隧道开挖过程进行三维数值模拟,分析了隧道开挖过程中主应力方向的旋转变化,研究了主应力旋转与隧道裂隙塑性变形的关系,验证了"考虑应力主轴旋转的广义塑性原理"的正确性,并将数值模拟结果和相关试验成果进行了对比,得出了一致性的结论。研究结果表明,应力旋转基本在隧道开挖前后10 m左右的距离内完成,隧道开挖过程中的应力旋转可以引起裂隙塑性变形的突变,且对竖向和斜向裂隙的影响较大;可以根据应力旋转的变化规律合理地选择支护时机,依据应力旋转对裂隙的影响对隧道的重点部位进行超前加固。Based on three-dimensional tunnel excavation simulation for a tunnel project,the rotation of principal stress direction during tunnel excavation was analyzed,the relationship between principal stress rotation and the plastic deformation of tunnel cracks was studied,the correctness of ＇generalized plastic principle considering the rotation of stress principal axis ＇ was verified.Contrast between simulation results with correlative test results was performed,with a coincident conclusion obtained.Results indicted,stress rotation completed within a distance of ten meters of the excavation,stress rotation during tunnel excavation could arouse the sudden change of plastic deformation of cracks,while the influences on vertical and oblique cracks were larger.In consequence,the supporting time could be chosen suitably by the variation regularity of stress rotation,advance reinforcment of the important parts of tunnel could be done based on the influence of stress rotation on cracks.

关 键 词：隧道开挖 三维数字模拟 应力旋转 裂隙发展 支护时机 超前加固 

分 类 号：U451.2[建筑科学—桥梁与隧道工程]