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通过煤岩的无侧限压缩试验测得其力学参数后,采用颗粒流软件和编制的Fish程序获得煤岩细观力学参数,而后进行双向不等侧压煤岩试验,分析研究煤岩变形、声发射和损伤特征,获得以下结论:随着侧压比增加,煤岩刚度角略增大,脆度角增大,强化角保持一定值,软化角先增大后减小;侧压比对煤岩的线性体缩阶段没有影响,对线性扩容阶段影响明显,对非线性扩容阶段影响显著。在非线性扩容阶段,低侧压比仍保持线性扩容,而高侧压比煤岩则急剧扩容失稳破坏;声发射最大强度与峰值应力并不对应,具有一定的滞后性,侧压比对声发射的滞后效应基本没有影响,声发射最大强度对应应力与峰值应力之比值大致在0.92左右;侧压比小时煤岩沿着单一剪切面发生剪切破坏,侧压比大时煤岩呈现X型共轭剪切破坏,且随着侧压比的增加,煤岩破坏的主控破裂面宽度加大,并逐渐形成破碎带,破碎带内煤岩呈粉碎性破坏状态。
Through the unconfined compressive test of coal and rock, the mechanical parameters of the rock were measured. Particle flow software and Fish program were used to obtain the meso-mechanics parameters of coal and rock. After that, Acoustic emission and damage characteristics. The following conclusions are obtained: With the increase of lateral pressure ratio, the rigidity of coal and rock slightly increases, the brittleness angle increases, the strengthening angle keeps a certain value, the softening angle first increases and then decreases; The linear shrinkage stage of coal and rock has no effect on the linear expansion stage, but has a significant impact on the nonlinear expansion stage. In the non-linear expansion stage, the low lateral pressure ratio still maintains a linear expansion, while the high lateral pressure coal is rapidly expanded and destabilized; the maximum acoustic emission intensity does not correspond to the peak stress, and has a certain degree of hysteresis. The lateral pressure ratio Acoustic emission lag effect basically no effect, the maximum acoustic emission intensity corresponding stress and peak stress ratio of about 0.92; lateral pressure ratio of coal along a single shearing plane shear failure occurs when the lateral pressure ratio is large coal rock X-type conjugate shear failure. With the increase of lateral pressure ratio, the width of the main rupture surface of coal and rock failure increases, and the crustal zone is gradually formed. The crushed coal and crushed rock are in a comminuted state.