To reveal the shear deformation and energy storage mechanism of composite roof strata, and to quantify the interlayer shear energy storage characteristics of composite roof strata, this study establishes a shear energy mechanical model for layered composite roof structures under various conditions. The factors influencing the shear energy storage of rock strata are analyzed, and the energy release process and mechanism of layered composite roof strata are discussed, leading to the following conclusions: the shear strain energy linearly increases with the increase in bond layer thickness and quadratically increases with increasing external forces. During the bending deformation stage, when thick and hard layers exist in the composite beams, shear failure dominated by interlayer shear slip occurs, and low-strength rock beams exhibit tensile crack initiation. In the overall instability stage, the composite beams mainly experience tensile fracture. When thick and hard layers exist in composite beams, the fracture strength and released energy are higher. The presence of thick and hard layers in the roof is a key factor leading to severe structural damage and increased energy release.
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