【摘要】 首先，利用线弹性近场动力学本构模型(linear peridynamic solids,LPS)对预切槽辅助滚刀破岩问题进行了模拟，并将数值结果与试验数据进行了对比；其次，设置了σ_x=5 MPa、σ_z=20 MPa和σ_x=20 MPa、σ_z=5 MPa这2种应力状态，0、9、18和30 mm这4种预切槽深度，总计8种工况；最后，研究了应力状态和预切槽深度对岩石破坏形态和破岩效率影响。研究结果表明：滚刀峰值贯入力随槽深的变化规律和岩石破坏形态与试验结果相符，从而验证了模型的可行性；在不同的槽深下，岩石存在2种破坏形态；当槽深为3 mm时，2个滚刀之间形成岩石破碎区；当槽深大于3 mm时，2个滚刀之间形成完整的岩块；当大主应力沿z方向时，会产生中央贯通裂纹；而当大主应力沿x方向时，则不会生成中央贯通裂纹；随着槽深增大，岩石损伤集中在预切槽附近区域，破岩效率也随之增高；当槽深≥18 mm时，峰值贯入力和比能较小，且两者受应力状态影响也较小。为实现不同应力条件下破岩性能的优化平衡、延长滚刀的使用寿命并降低施工成本，建议预切槽深度不小于18 mm；当预切槽深度无法达到该要求时，可在水平方向为大主应力方向时适当增加预切槽深度。更多还原

【Abstract】 Firstly, the linear peridynamic solids model(LPS) was used to simulate the pre-cut groove-assisted rock fragmentation caused by disc cutters, and the numerical results were compared with experimental results.Secondly, two stress states(σ_x=5 MPa, σ_z=20 MPa and σ_x=20 MPa, σ_z=5 MPa) and four pre-cut groove depths of 0,9, 18, and 30 mm were set, resulting in a total of 8 conditions. Finally, the effects of stress state and pre-cut groove depth on rock failure morphology and rock breaking efficiency were investigated. The results show that the variation pattern of the peak cutter penetration force with pre-cut groove depth and the rock failure morphology are consistent with the experimental data, thereby validating the feasibility of the model. Under different groove depths, two failure modes of the rock were observed. When the groove depth is 3 mm, a rock fragmentation zone is formed between the two cutters. When the groove depth is greater than 3 mm, a complete rock block is formed between the two cutters. When the major principal stress is along the z-direction, central through-cracks are formed. When the major principal stress is along the x-direction, no central through-cracks are formed; as the groove depth increases, the rock damage becomes concentrated near the pre-cut groove region, and the rock breaking efficiency increases. When the groove depth is not less than 18 mm, the peak penetration force and specific energy are smaller, and both are less affected by the stress state. To achieve an optimal balance in rock breaking performance under different stress conditions, extend the disc cutter’s service life, and reduce construction costs, it is recommended that the pre-cut groove depth should be no less than 18 mm. If this depth cannot be achieved, it is recommended to appropriately increase the pre-cut groove depth when the major principal stress is along the horizontal direction.更多还原