Effect of induction unloading on weakening of rock mechanics properties  

诱导卸荷对岩石力学性质弱化的影响(英文)

作　　者：高峰[1] 周科平[1] 罗先伟[1] 翟建波[1] 

机构地区：[1]中南大学资源与安全工程学院,长沙410083

出　　处：《Transactions of Nonferrous Metals Society of China》2012年第2期419-424,共6页中国有色金属学报（英文版）

基　　金：Project (51074178) supported by the National Natural Science Foundation of China;Project (20110162120056) supported by the Special Research Fund for the Doctoral Program of Higher Education of China;Project (2011QNZT089) supported by the Young Teachers Boosting Special Subject of Central South University,China

摘　　要：The effects of induction unloading such as drilling, blasting, lancing and water-infusion softening on weakening of rock mechanics properties were investigated. Three stress paths were chosen as test schemes corresponding to the triaxial compressive test, pre-peak and post-peak unloading the confining pressure tests. The results show that compression deformation is the main cause of rock failure under loading condition. However, the strong dilatation leads to the rock failure along unloading direction. Rock failure happens even under little axial stress with confining pressure unloading. Poisson ratio increases with the decrease of confining pressure during the process of unloading. Elastic modulus increases slowly along with the decline of confining pressure, but decreases rapidly when unloaded to yielding strength. It shows that the weakening rate of rock intensity tends to be faster with easily failure under the unloading condition.研究在诱导卸荷作用下如钻孔、爆破、切缝和注水软化岩石的力学性能弱化规律。设计常规三轴加载、峰前和峰后卸载三种试验方案。试验结果表明:加载条件下的岩石破坏主要是由压缩变形所致,而卸荷条件下沿卸荷方向的岩石破坏为强烈的扩容所致。只要存在卸荷作用,岩石在较小的轴向应力下便可以发生破坏,甚至是强烈的脆性破坏。同时,卸荷过程中岩石泊松比随围压的降低逐渐增大。弹性模量随围压的减小先缓慢增加,在达到屈服强度后迅速降低。试验证明卸荷作用下岩石的强度弱化速率更快。

关 键 词：induction caving UNLOADING deformation feature fracture mechanism 

分 类 号：TU45[建筑科学—岩土工程]