采矿与岩层控制工程学报2025，Vol.7Issue(6)：176-191,16.DOI:10.13532/j.jmsce.cn10-1638/td.2025-1119
低频动力扰动下高应力煤柱渐进损伤破坏特征及机理研究
Progressive damage failure characteristics and mechanism of high-stress coal pillar under low-frequency dynamic disturbance
摘要
Abstract
When the mining face approaches the coal pillar,dynamic instability occurs in front coal pillar.To explore the influence mechanism of mining disturbance on dynamic instability of coal pillar,the dynamic compression test of high-stress coal pillar under low-frequency disturbance load was carried out.The results show there is a stress threshold value for the failure of coal samples under high stress(80%of the Unilateral Constrained Compressive Strength(UCCS)),and the threshold value is 15%of UCCS.Subjecting to the stress over the threshold value,the number of disturbance load cycles before the failure of high-stress coal samples decreases exponentially with the increase of amplitude,and the increase of amplitude significantly deteriorates the bearing capacity of coal samples.Also,the irreversible strain,dissipated energy,secant modulus and damping ratio of coal samples show a three-stage evolution law under disturbance load.In addition,with the increase of amplitude,the cumulative dissipated energy in the process of coal sample disturbance increases linearly with the maximum value of 241.932 kJ/m3.The mean value of secant modulus decreases linearly with the minimum value of 1.101 GPa.However,the mean value of damping ratio increases exponentially with the maximum damping ratio of 1.593,indicating the increase of amplitude makes the internal deterioration of coal sample more serious.The large increase of AE energy in the initial disturbance loading stage of coal sample can be used as an advanced criterion to judge whether the coal sample is damaged,and the second surge of cumulative ring count can be used as the precursor information of coal damage beyond the threshold value.With the increase of amplitude,the b value of AE in the whole disturbance loading process on coal decreases linearly with the minimum value of 1.369.In other words,the larger the amplitude,the more sudden and severe the damage of coal sample.With the increase of amplitude,the fracture mode of coal samples when subjecting to stress beyond the threshold gradually changes from shear fracture to tensile or mixed fracture.关键词
扰动荷载幅值/高应力/能量耗散/AE特征Key words
disturbance load amplitude/high stress/energy dissipation/AE characteristics分类
矿业与冶金引用本文复制引用
冯文明,陈添明,郭军,冯国瑞,白锦文,罗文,文晓泽,张亮,刘全,李丽绒..低频动力扰动下高应力煤柱渐进损伤破坏特征及机理研究[J].采矿与岩层控制工程学报,2025,7(6):176-191,16.基金项目
国家自然科学基金面上资助项目(52474142) （52474142）
山西省基础研究计划自然科学研究面上资助项目(202303021211062) （202303021211062）
国家自然科学青年科学基金资助项目(52525401) （52525401）
