岩土力学Issue(4)：913-918,925,7.
硬岩裂纹起裂强度和损伤强度取值方法探讨
Discussion on methods for calculating crack initiation strength and crack damage strength for hard rock
摘要
Abstract
Strength thresholds of crack initiation (ci ) and crack damage (cd ) of hard rock are of great significance not only for understanding the progressive failure process and brittle failure mechanism but also for establishing the crack initiation strength criterion and long-term strength criterion. In view of this, four methods to calculate the crack initiation and damage strength, including crack volumetric strain model, acoustic emission method, lateral strain and volumetric strain observation method, moving point regression technique, are summarized systematically;and marble and granite in uniaxial stress state are taken as examples to show problems in determining ci and cd by each method. Results show that ci and cd can be obtained conveniently and precisely through crack volumetric strain model which has a clear physical meaning;progressive failure and damage process of rock can be comprehended qualitatively or semi-quantitatively by analysis of acoustic emission hit rate; but ci and cd can not be acquired accurately. Curve of volumetric strain stiffness is strongly influenced by data intervals and characteristics of different stages during loading are not obvious when moving point regression technique is used, which makes the determination of ci difficult. The result could contribute to understanding the importance and calculating methods of crack initiation and damage strength thresholds and provide a useful reference to choose appropriate calculating method.关键词
起裂强度/损伤强度/声发射/体积应变刚度/计算方法Key words
crack initiation strength/crack damage strength/acoustic emission/volumetric strain stiffness/calculating method分类
建筑与水利引用本文复制引用
周辉,孟凡震,卢景景,张传庆,杨凡杰..硬岩裂纹起裂强度和损伤强度取值方法探讨[J].岩土力学,2014,(4):913-918,925,7.基金项目
国家重点基础研究发展计划（973）项目(No.2014CB046902)；中国科学院科技创新“交叉与合作团队”(人教字〔2012〕119号)；中国科学院知识创新工程重要方向项目(No. KZCX2-EW-QN115)；国家自然科学基金项目(No.41172288)。 （No.2014CB046902）
