摘要
岩石的失稳破坏是岩石力学的一个重要课题。本文根据微观原子键作用的特征,揭示了固体材料宏观破坏本质必然是微观键的拉破坏,发明了键弹簧,用以表征岩石宏观力学性质。在综合分析岩石破坏的宏细观特征及声发射特性的基础上,建立了岩石破坏的键弹簧模型,推导出用以判别系统失稳的虚余能判据。利用虚余能判据,对各种加载状态下岩石的失稳破坏进行了综合分析,讨论了岩石在单轴拉伸、压缩、剪切、真三轴单面卸载等条件下的失稳条件,及岩石系统失稳破坏的尺度效应和围压效应。进一步提出了岩石系统失稳的统一判据公式,指出系统加载失稳由加载条件、应力状态、几何参数共同决定,区别于传统系统失稳的刚度理论。最后介绍了岩石键弹簧模型失稳判据在工程上的应用。
It is well known that rock failure is one of the most important issues in rock mechanics. Based on analyses of the micro action of bond between atoms,it is found that the tension break of the micro bond is the only direct way of the macro failure for any solid material. A bond spring is made to represent the themacro mechanical characteristics of rocks. A bond spring model of rock failure is given upon the comprehensive analysis of the macro characteristics and AE during rock failure. With this model,a criterion for system destabilization is induced,which was called visual remaining energy（ VRE）. VRE criteria are applied to analyze the unstable failure of rock on different loading conditions,and destabilization criteria are given for uniaxial compression,tension and shear. One face unloading under the real triaxial loading with size effect and confining pressure effect is discussed. Furthermore,a uniform destabilization formula is established for a rock system,which is different from the traditional stiffness destabilization theory. The system destabilization is determined by factors of loading condition,stress state and geometry. Two engineering applications of the criteria are also given.
出处
《水文地质工程地质》
CAS
CSCD
北大核心
2014年第5期38-43,共6页
Hydrogeology & Engineering Geology
关键词
岩石破坏
键弹簧模型
失稳判据
冲击地压
rock failure
bond spring model
destabilization criteria
bump
