Shandong Xinjulong Energy Co., Ltd.

为研究煤岩组合体宏观强度和细观裂纹发育扩展特征,利用离散元方法分析了不同强度比下煤岩组合体强度和破坏行为。结果表明,煤体结构较弱时,组合体承载能力相对较低,强度特征也最低;随着煤体结构属性增加,组合体承载能力相对增加,组合体起裂应力、峰值强度、峰值应变和弹性模量也逐渐增加;煤岩强度比为0.1时,声发射事件相对连续,随着煤岩强度比增加,AE事件数逐渐分散,声发射事件数最大值也逐渐增加;煤岩组合体试样起裂位置均位于煤体结构内,煤体颗粒和岩石颗粒强度差异大时煤体破坏导致试样整体失稳,强度差异小时裂纹能够穿过岩石。

To study the macroscopic strength and microscopic crack development and propagation characteristics of coal rock combination body, the discrete element method is used to analyze the strength and failure behaviors of coal rock combination body under different strength ratios. The results indicate that when the coal body structure is weak, the load-bearing capacity of the combination body is relatively low, and the strength characteristics are also the lowest; As the structural properties of coal body increase, the load-bearing capacity of the combination body increases relatively, and the crack initiation stress, peak value strength, peak value strain, and elastic modulus of the combination body also gradually increase; When the coal rock strength ratio is 0.1, the acoustic emission events are relatively continuous. As the coal rock strength ratio increases, the number of AE events gradually disperses, and the maximum number of acoustic emission events also gradually increases; The crack initiation positions of coal rock combination body samples are all located within the coal body structure. When the strength difference between coal body particles and rock particles is large, coal body failure leads to overall instability of the sample. When the strength difference is small, cracks can penetrate the rock.