为了探究不同冲击载荷作用下煤体破裂失稳动力学特征与能量耗散规律，采用改进的霍普金森压杆（SHPB）试验系统，分别开展了一维冲击载荷、冲击载荷与轴向静载耦合作用动力学试验，研究了不同冲击速度和轴向静载下煤样动力学特性，分析煤样宏观破裂形态和孔隙演化规律，并从能量耗散角度剖析煤岩破裂失稳机制。研究结果表明：不同冲击载荷扰动下煤样应力−应变曲线均包含线弹性、塑性和塑性软化3个阶段。一维冲击载荷作用下煤样峰值强度和峰值应变具有明显的应变率效应，随着应变率的增加，煤样峰值强度、峰值应变逐渐增大；筛分统计破裂碎块不同粒径的质量分布，随应变率的增大，较大粒径质量减少、小粒径质量增加；煤样的入射能、反射能和耗散能均随冲击载荷的增大而逐渐增加，能量耗散密度呈指数增长；在冲击载荷与轴向静载耦合作用下，设定5.54 m/s的低速冲击载荷，随着轴向静载递增，峰值强度持续提升，峰值应变线性减弱；基于核磁共振（NMR）测试表征孔隙结构，煤样内部微孔随轴向静载的增大不断发育，裂隙沿轴向扩张趋势增加；煤样入射能随轴向静载的不断增加基本保持稳定，反射能不断减小，耗散能逐渐增大，能量耗散密度呈线性关系增大。根据煤岩能量耗散机制，孔隙萌生、扩展和贯通诱导煤体产生破裂失稳；轴向静载作用初期更多耗散能被用于内部微孔发育和裂隙扩张，随轴向静载的增大，裂隙不断扩展、滑移衍生出更多潜在破裂面；冲击载荷瞬时扰动下会诱导煤体形成宏观破裂面，产生大范围破裂失稳现象。

To explore the dynamic characteristics and energy dissipation laws of coal fracture instability under varied impact loads, using an improved Hopkinson bar (SHPB) test system was used to conduct one-dimensional impact load, impact load and axial static load coupling dynamic tests. The dynamic characteristics of coal samples under different impact speeds and axial static loads were studied, analyzing the macroscopic fracture morphology and pore evolution of coal samples were analyzed, the mechanism of coal rock fracture instability from the perspective of energy dissipation. The research results indicate that the stress-strain curves of coal samples under different impact load disturbances all include three stages: linear elasticity, plasticity, and plastic softening. Under one-dimensional impact load, the peak strength and peak strain of coal samples exhibit significant strain rate effects. As the strain rate increases, the peak strength and peak strain of coal samples gradually increase; Screening statistics show the mass distribution of broken fragments with different particle sizes. As the strain rate increases, the mass of larger particles decreases while the mass of smaller particles increases; The incident energy, reflected energy, and dissipated energy of coal samples gradually increase with the increase of impact load, and the energy dissipation density increases exponentially; Under the coupling effect of impact load and axial static load, a low-speed impact load of 5.54 m/s is set. As the axial static load increases, the peak strength continues to increase and the peak strain linearly weakens; Based on the characterization of pore structure using nuclear magnetic resonance (NMR) experiments, the internal micropores of coal samples continuously develop with the increase of axial static load, and the expansion trend of cracks along the axial direction increases; The incident energy of coal samples remains stable with the continuous increase of axial static load, while the reflection energy decreases and the dissipation energy gradually increases. The energy dissipation density increases linearly. According to the energy dissipation mechanism of coal rock, the initiation, expansion, and penetration of pores induce the occurrence of fracture and instability in coal; In the initial stage of axial static load, more dissipated energy was used for the development of internal micropores and crack expansion. Under the instantaneous disturbance of impact loads, the formation of macroscopic fracture within the coal is induced, which ultimately results in large-scale fracture instability. Under the instantaneous disturbance of impact load, it will induce the formation of macroscopic fracture surfaces in the coal body, resulting in large-scale fracture instability.