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Field investigations have proven that layer‐crack structures make an essential contribution to rock burst occurrence in brittle coal or rock mass. This paper first studies the mechanical behavior of layer‐crack red sandstone specimens with different geometric configurations of vertical fissures (ie, fissure width, fissure length, and fissure number) through uniaxial compression and Brazilian tests. Then, the digital speckle correlation method (DSCM) and acoustic emission (AE) technique are used to record the deformation and failure processes. Finally, the failure mechanisms of the layer‐crack structure are presented and discussed. Under compressive conditions, the failure process can be divided into compatible support, incompatible support, and postpeak unstable failure stages. An increase in fissure width, as well as fissure length or number, causes an increase in the inner damage accumulation and a decrease in the stiffness coefficient by decreasing the strain of the compatible support stage. Thus, the bearing capacity of the layer‐crack structure is weakened. Under tensile conditions, the tensile ability decreases linearly as the fissure length increases, but the vertical pressure acting on the fissure increases linearly as the fissure width increases. Thus, the tensile strength of the layer‐crack structure decreases as the fissure length (or width) increases.

In order to research the influence of homogeneity on the rockburst tendency and on AE characteristics of coal-rock combination body, uniaxial compressive tests of inhomogeneous coal-rock combination bodies obeyed by the Weibull distribution were simulated using particle flow code (PFC2D). Macromechanical properties, energy evolution law, and AE characteristics were analyzed. The results show that (1) the elastic modulus homogeneitymEhas an exponential relation with macroscopic modulusE, and the bonding strength homogeneitymσhas an exponential relation with uniaxial compressive strengthσc; (2) the rockburst tendency of the coal-rock combination body will increase with the increase ofmEormσ, andmσis the leading factor influencing this tendency; and (3) both the change law of AE hits and lasting time in different periods of AE characteristics are influenced bymσ, butmEjust influences the lasting time. The more inhomogeneous the coal-rock combination body is, the shorter the lasting time in booming period of AE characteristics will be. This phenomenon can be used to predict the rockburst tendency of the coal-rock combination body.

Destress drilling method is one of the commonly used methods for mitigating rock bursts, especially in coal mining. To better understand the influences of drilling arrangements on the destress effect is beneficial for rock burst mitigation. This study first introduced the rock burst mitigation mechanism of the destress drilling method and then numerically investigated the influences of drilling arrangements on the mechanical properties of coal models through uniaxial compression tests. Based on the test results, the energy evolution (i.e., the energy dissipation and bursting energy indexes) influenced by different drilling arrangements was analyzed. When the drilling diameter, the number of drilling holes in one row, or the number of drilling rows increases, the bearing capacity of specimens nonlinearly decreases, but the energy dissipation index increases. In addition, the drilling diameter or the number of drilling holes in one row affects the failure mode weakly, which is different from that of the number of drilling rows. Consequently, the bursting energy index decreases as increasing the drilling diameter or the number of drilling holes in one row, but as increasing the number of drilling rows, the variation law of bursting energy index is not obvious. At last, the influencing mechanism of drilling arrangement on the rock burst prevention mechanism of the destress drilling method was discussed and revealed.

Many case studies have revealed that rock bursts generally occur in high stress concentration areas where layer-crack structures often exist, especially for brittle coal or rock masses. Understanding the mechanical behavior of layer-crack rocks is beneficial for rational design and stability analysis of rock engineering project and rock burst prevention. This study numerically investigated the influence of vertical fissure geometric configurations on the mechanical behavior of layer-crack rock models through uniaxial compression tests. Results reveal that the deformation and strength behaviors of layer-crack specimens depend on the vertical fissure geometric configurations, which also influence the crack evolution process. In aspect of failure mode, it is splitting failure or shear failure of the whole layer-crack specimen when the fissure length is smaller than 40 mm, but it is splitting failure or shear failure of supporting bodies in other conditions. Among the three factors, the influencing degree in order from strong to weak is fissure number, fissure length, and fissure width. Meanwhile, the influence of fissure geometric configurations on the failure mechanism of layer-crack structure and the occurrence mechanism of rock burst were revealed. In addition, some advices for keeping the stability of layer-crack structure and mitigating rock bursts were given.