非均质结构含量对煤岩组合体强度及破坏特征的影响

Effect of Heterogeneous Structure Content on Strength and Failure Characteristics of Coal-Rock Combination

为研究非均质结构含量对煤岩组合体强度及破坏演化特征的影响,基于离散元软件,建立了不同非均质结构含量的煤岩组合体模型,考虑非均质结构含量为10%、30%、50%、70%和90%这5种方案,对煤岩组合体的强度特征、裂纹发育扩展过程进行了研究,分析了其影响机理。结果表明:随非均质结构含量的增加,煤岩组合体强度参数整体呈下降趋势,煤岩组合体声发射平静期范围呈先减小后增大趋势,声发射骤增期呈上升趋势;非均质结构与煤岩颗粒的属性差异导致了局部应力集中;非均质结构含量变化决定了试样强度特征和最终破坏模式,随非均质结构含量增加,煤岩和非均质结构中的主要承载结构由煤岩转变为非均质结构。

In order to study on effect of heterogeneous structure content on strength and failure characteristics of coal-rock combination,models with various levels of heterogeneous structure content 10%,30%,50%,70%and 90%were created using discrete element software to examine the effects of heterogeneous structure content on the strength and failure characteristics of coal-rock combinations.Coal and rock combinations′strength properties and crack growth were examined,and the influencing mechanism was examined.The findings showed that the strength parameters of the coal and rock mass declined as the heterogeneous structure content rose,and that the AE quiet period first fell before increasing and then showing an upward trend.This resulted from the localized concentration of stress brought on by variations in the heterogeneous structure and coal particle characteristics.The strength parameters and ultimate failure mode of the samples were determined by the variation in heterogeneous structure composition.The primary bearing structure changed from coal rock to heterogeneous structure as the quantity of heterogeneous structure increased.