采矿与岩层控制工程学报2025，Vol.7Issue(1)：18-33,16.DOI:10.13532/j.jmsce.cn10-1638/td.2024-1393
动载循环作用下砂岩的动态力学响应及破坏特征
Dynamic mechanical response and failure characteristics of sandstone under dynamic load cycle
摘要
Abstract
For the poor self-stability of rock mass and frequent dynamic disasters in the process of deep mine mining,the uniaxial dynamic load disturbance test of sandstone with different amplitudes and frequencies were carried out using the self-developed ZST-1500 microcomputer controlled electro-hydraulic servo coal and rock dynamic and static combination adaptive coupling test system,and the dynamic mechanical response law and failure characteristics of sandstone under dynamic load were analyzed.The results show that with the increase of dynamic load amplitude,the hysteresis loop of sandstone changes from"sparse-dense"to"sparse-dense-sparse",and the dynamic load cycle is divided into logarithmic rising stage I,uniform damage stage II and exponential acceleration stage III according to the plastic deformation of the sample during the dynamic load cycle.There is a threshold for the weakening effect of dynamic load on the strength of the specimen when the dynamic load level is 70%σc.The amplitude threshold of failure is 17.5%～22.5%σc,and the dynamic load below the threshold value will not cause sandstone instability.The sandstone strength and the dynamic load duration before failure are negatively correlated with the dynamic load amplitude and frequency beyond the threshold value.The effect of dynamic load amplitude and frequency on the weakening mechanism of sandstone is different.Both the dynamic load amplitude and frequency are positively correlated with the average plastic deformationΔ(ε¯)(i)in every single cycle of dynamic load,butΔ(ε¯)(i)is more sensitive to the dynamic load amplitude and increases exponentially with the increase of the amplitude in the stages of I and II.The dynamic load amplitude weakens the sandstone mainly by increasing the plastic deformation,while the increase of frequency reduces the cyclic interval of dynamic load,and forms a small amount of continuous damage in sandstone in short time,thus weakening the sandstone.The cumulative energy and ringing count rate of sandstone AE signals increase exponentially with the increase of dynamic load amplitude,and also increases synchronously with the increase of dynamic load frequency.With the increase of dynamic load amplitude,the initiation and propagation degree of sandstone micro-cracks increase,and the proportion of shear cracks increases.Also,the proportion of sandstone tensile cracks increases with the increase of dynamic load frequency.关键词
岩石力学/砂岩/循环动载/动态力学响应/渐进损伤Key words
rock mechanics/sandstone/cyclic loading/dynamic mechanical response/progressive damage分类
矿业与冶金引用本文复制引用
赵光明,秦志宏,孟祥瑞..动载循环作用下砂岩的动态力学响应及破坏特征[J].采矿与岩层控制工程学报,2025,7(1):18-33,16.基金项目
国家重点研发计划资助项目(2023YFC2907602) （2023YFC2907602）
安徽省高校优秀科研创新团队资助项目(2022AH010053) （2022AH010053）
国家自然科学基金资助项目(52342404) （52342404）
安徽省科技重大专项资助项目(202203a07020011) （202203a07020011）
高校协同创新资助项目(GXXT-2021-075) （GXXT-2021-075）
