摘要
根据微损伤不可逆演化原理,利用有限元模型,模拟隧道断面在自适应位移加载条件下,从点状微损伤斑图到宏观贯通断裂的不可逆的跨尺度生长过程。模拟显示的破坏区与现场观察非常一致。岩爆的孕育演化是大大小小的"V"形裂隙带将岩爆体从完整母岩中分划出来的过程。岩爆演化的细观力学机制研究表明,裂隙带扩展受滑移驱动作用控制,其扩展方向与最大剪切滑移方向一致,裂隙带的宏观表现是滑移带,内部具有张拉破裂的细观机制。随着滑移带扩展,最后可形成两个驱动核组成的驱动团,它们从相对方向将裂隙带贯通。裂隙带贯通前,驱动团上的承载力明显增大。岩爆孕育过程的声发射、微震或电磁、热效应监测对于岩石类动力灾害的临兆预测具有重要意义。
According to the principle of irreversible damage evolution,the finite element model was adopted to simulate the irreversible trans-scale growth of cross-section of deeply-buried tunnel from point-shaped micro-damages to band-shaped fractures at the loading of self-adaptive displacements.The damaged area in the simulation was consistent with that observed on site.The gestation and evolution of rock-burst is a process in which a lot of V-shaped fracture zones with different size separate from the surrounding rock of tunnel by a rock burst.The study on meso-mechanism for the evolution of rock burst indicated that expansion of fracture zones was limited by the driving force of shear sliding,with expansion direction being in line with the shear sliding direction.So macroscopically,the fracture zone is a sliding band,but with tensile crack in term of meso-mechanism.With the expansion of the fracture zone,two driving groups with driving kernels run through fracture zone in the opposite directions.The bearing capacity of driving groups obviously increased before running through fracture zone.Monitoring of acoustic emission,microseism or electromagnetic wave and thermo-effect will be of important significance in predicting dynamic catastrophe in rock mass.
出处
《矿冶工程》
CAS
CSCD
北大核心
2011年第4期14-17,共4页
Mining and Metallurgical Engineering
基金
国家863项目(2008Aa06204)
关键词
深埋隧洞
岩爆
孕育
数值模拟
滑移裂隙带
deeply-buried tunnel
rock burst
gestation
numeric simulation
fracture zone
