摘要
为了研究不同冲击倾向性煤样在循环载荷下的力学特征及能量演化规律,对强冲击倾向性煤样、弱冲击倾向性煤样和无冲击倾向性煤样进行系统分析,并提出了弹性能释放速率及计算方法,得到不同冲击倾向性煤样循环载荷下应力-应变曲线的特征、应变变化规律及耗散能和弹性能转化规律,给出不同冲击倾向性煤样破坏与能量演化关系。研究结论如下:无冲击倾向性煤样应力-应变曲线具有疏-密的特征,弱冲击倾向性煤样应力-应变曲线具有疏-密-疏的特征,强冲击倾向性煤样应力-应变曲线具有密的特征;随着冲击倾向性的增加,卸载峰值应变及平均卸载应变均在逐渐的减小;强、弱和无冲击倾向性煤样平均峰值应变整体呈现先增加后减小的趋势;随着循环次数的增加,耗散能整体也呈现先减少后增加的趋势,弹性能也越来越大且呈现近线性的增长;弹性能量指数呈现先增大后减小的趋势,局部出现波动;随着冲击倾向性增强,塑性能的消耗越少,储存的弹性能越多,破坏时转化的能量也就越多。
In order to study the mechanical properties and energy evolution law of coal samples with different impact tendency under cyclic load,the systematic analysis of coal samples with strong,weak and non-impact tendency is carried out,and the release rate and calculation method of elastic energy are put forward.The law,strain change law,dissipation energy and elastic energy transformation of stress-strain curve under cyclic load of coal samples with different impact tendency are obtained.The results show that the stress-strain curve of non-impact coal sample has the law of sparse dense,the stress-strain curve of weak impact coal sample has the law of sparse dense,and the stress-strain curve of strong impact coal sample has the law of dense.With the increase of impact tendency,the peak unloading strain and the average unloading strain decrease gradually.The average peak strain of strong,weak and non-impact coal samples increases first and then decreases.With the increase of the number of cycles,the dissipation energy decreases firstly and then increases,and the elastic energy increases more and more.The elastic energy index increases firstly and then decreases,and fluctuates locally.With the increase of impact tendency,the less the consumption of plastic properties in the process of cyclic loading,the more elastic energy stored,and the more energy converted during failure.
作者
武成家
秦涛
刘振文
刘刚
WU Chengjia;QIN Tao;LIU Zhenwen;LIU Gang(School of Safety Engineering,Heilongjiang University of Science and Technology,Harbin 150022,China;School of Mining Engineering,Heilongjiang University of Science and Technology,Harbin 150022,China;School of Resources and Civil Engineering,Northeastern University,Shenyang 110819,China)
出处
《中国矿业》
2021年第2期160-166,共7页
China Mining Magazine
基金
国家自然科学基金项目资助(编号:51674107,51604100)
黑龙江省自然科学基金联合引导项目资助(编号:LH2019E087)。
关键词
冲击地压
力学特性
弹性能量指数
能量演化
煤样
rockburst
mechanical property
elastic energy index
energy evolution
coal sample
