煤岩高度比对组合体力学特性影响的数值分析

Numerical Analysis on Mechanical Characteristics of Coal-rock Combination of Different Height Ratios

通过颗粒离散元程序建立了3种不同煤岩高度比的煤岩组合模型,分析和比较了单轴压缩作用下的强度和破坏形态,并以此为基础建立煤岩力学结构模型,分析了煤岩组合体在压缩作用下的变形破坏过程。研究结果表明:煤岩组合体的强度介于煤体和岩体之间,其破坏形态主要受到煤体部分的影响;煤岩组合体的变形破坏过程比煤、岩单体更加复杂,尤其在塑性屈服和峰值破坏阶段;组合体的应力-应变曲线在峰值附近表现出明显的波动性,即组合体的变形破坏过程为典型的渐进式破坏。

Three kinds of coal-rock combination models with different ratios are established by means of particle discrete element program, and strength and failure modes under uniaxial compression are analyzed and compared. On the basis of this,a mechanical model of coal-rock combination is established, and the failure process of coal-rock combination under uniaxial compression is analyzed. The results show that the strength of coal-rock combination is between coal and rock, and the failure mode is mainly affected by the coal body part,the deformation and failure process of coal-rock combination is more complex especially in the plastic yield and peak failure stage, and the stress-strain curve of the combination exhibits obvious fluctuation near the peak and deformation and failure process is a typical progressive failure mechanism.