循环冲击作用下岩石应力应变曲线及应力波特性  

Stress-strain curve and stress wave characteristics of rock subjected to cyclic impact loadings

作　　者：金解放[1] 李夕兵[2] 常军然[3] 陶伟[1] 邱灿[1] 

机构地区：[1]江西理工大学建筑与测绘工程学院,江西赣州341000 [2]中南大学资源与安全工程学院,湖南长沙410083 [3]江西理工大学应用科学学院,江西赣州341000

出　　处：《爆炸与冲击》2013年第6期613-619,共7页Explosion and Shock Waves

基　　金：国家自然科学基金项目(51104068)~~

摘　　要：利用研制的岩石动静组合加载实验装置进行循环冲击实验,研究了在循环冲击过程中岩石典型的动态应力应变曲线及反射波和透射波的变化规律。结果表明:岩石在循环冲击过程中的动态应力应变曲线可分为压密阶段、弹性阶段、内部裂纹扩展的加载阶段、第1卸载阶段和第2卸载阶段等5个阶段。在相同入射波循环作用下,随着循环次数的增加,岩石的反射波峰值越来越大,反射波峰值出现的时间越来越迟,透射波峰值越来越小,透射波峰值出现的时间越来越早,表明在循环冲击过程中岩石内部损伤逐渐累积,从而导致抵抗外部冲击载荷的能力逐渐降低。An innovative testing technique coupled by static and dynamic loads was introduced to investigate the typical dynamic stress-strain curve of the rock specimen under cyclic impact loadings as well as the changes of the reflected and transmitted waves propagating in it.The results show that the single typical stress-strain curve of the rock specimen under cyclic impacts can be divided into five stages：the compacted stage,the elastic stage,the loading stage of the internal crack propagation,the first unloading stage and the second unloading stage.With the increase in the number of impact,the amplitude of the reflected wave increases and the corresponding peak value appears later; the amplitude of the transmitted wave decreases and the corresponding peak value occur increasingly earlier,respectively.It is demonstrated that the cyclic impacts on the rock specimen are accompanied by the damage accumulation resulting in the reducing of its ability to resist the external impact loads.

关 键 词：固体力学 动态应力应变曲线 循环冲击 岩石 应力波特征 损伤累积 强度劣化 

分 类 号：O347.3[理学—固体力学]