考虑损伤和扩容影响的隧洞围岩稳定性分析  

Stability analysis of tunnel surrounding rock considering influence of damage and dilatancy

作　　者：高召宁[1] 陈登国 孙振川 杨延栋 李顺顺 GAO Zhaoning;CHEN Dengguo;SUN Zhenchuan;YANG YanDong;LI Shunshun(School of Energy and Safety,Anhui University of Science and Technology,Huainan Anhui 232001,China;State Key Laboratory of Shield Tunneling Technology,Zhengzhou Henan 450001,China)

机构地区：[1]安徽理工大学能源与安全学院,安徽淮南232001 [2]盾构及掘进技术国家重点实验室,河南郑州450001

出　　处：《中国安全科学学报》2020年第7期159-165,共7页China Safety Science Journal

基　　金：国家自然科学基金资助(51174255)。

摘　　要：为解决复杂地质构造条件下隧洞开挖后围岩支护问题,根据围岩应力分布曲线特征,将围岩划分为弹性区和塑性区。结合Drucker-Prager屈服准则,建立围岩弹塑性损伤本构模型,分析隧洞开挖后引起的围岩损伤力学性能劣化和卸载时扩容效应的作用,推导出隧洞围岩在损伤和扩容条件下弹塑性区的解析解。研究表明:随着损伤和扩容程度的增加,支护阻力和塑性区位移明显增大;塑性区半径越大时,切向应力峰值远离隧洞壁,在一定范围内对围岩的稳定影响越深;随着中间主应力系数的增大,支护阻力随之减小,考虑中间主应力系数时对支护参数的优化更加有利。In order to solve supporting problems of surrounding rock after tunnel excavation under complex geological structure,surrounding rock was divided into elastic zone and plastic zone according to characteristics of its stress distribution curves.Then,an elastoplastic damage constitutive model was developed following Drucker Prager yield criterion,and its mechanical performance degradation caused from damages and dilatancy under unloading were analyzed.Finally,an analytical solution of elastic-plastic zone was deduced.The results show that support resistance and plastic areas’shift increase obviously as injury and dilatancy degree intensifies.The bigger radius of plastic zone is,influence on surrounding rock stability is deeper within a certain range since tangential stress peak is far away from tunnel wall.And along with increase of intermediate principal stress coefficient,support resistance decreases,which is more favorable to optimization of support parameters with an consideration to the former.

关 键 词：损伤 扩容效应 隧洞围岩 弹塑性 应力 

分 类 号：X935[环境科学与工程—安全科学]