为研究冲击速度、层理角度及切缝深度对煤样Ⅰ型动态断裂裂纹扩展速度与扩展路径等断裂特性的影响，结合分离式霍普金森压杆(SHPB)试验和基于连续-非连续单元方法(CDEM)的数值模拟，对3种切缝深度的直槽半圆弯曲煤样(NSCB)开展不同层理角度和多种加载速率下的Ⅰ型动态断裂测试与数值模拟研究。得到煤样在冲击载荷下裂纹萌生、演化、扩展及贯通的渐进破坏全过程，模拟与试验结果吻合较好，证明CDEM数值模拟方法能够较好地模拟煤样Ⅰ型动态断裂从连续到非连续的渐进破坏过程。研究表明:煤样裂纹瞬时扩展速度随时间变化波动性较大，前期扩展较快，后期扩展较慢，可将试件裂纹扩展分为高速扩展阶段和稳速扩展阶段;冲击速度对裂纹平均扩展速度影响最大，切缝深度次之，层理角度影响最小。裂纹平均扩展速度随冲击速度增大而增大，但渐趋于平缓，而随切缝深度增加逐级降低。并在忽略层理角度影响的情况下，得出冲击速度与切缝深度对裂纹平均扩展速度的双因素预测模型;冲击速度越大，裂纹起裂时间越短，但其对裂纹扩展路径影响很小。层理角度对裂纹起裂时间基本没有影响，但对裂纹扩展路径影响较大。层理角度为0°和90°时，煤样裂纹最为平直，层理角度为22.5°,45.0°和67.5°时裂纹较弯曲，出现沿层理面扩展现象。

In order to study the influence of impact speed,bedding angle and notch length on the speed and path of crack propagation of model Ⅰ dynamic fracturing of coal,the split Hopkinson pressure bar test and numerical simulation based on continuum-discontinuum element method are carried out.The notched semi-circular bending specimens with different bedding angles and three notch lengths are impacted under various loading rates.The whole fracturing process from the initiation,the propagation to the failure of the specimen is monitored.The simulation results also agree well with the test results.It is proved that the CDEM numerical simulation method can better simulate the progressive failure process of coal from continuous to discontinuous.The experimental results indicate that the instantaneous crack propagation speed of coal specimen fluctuates greatly,and the crack propagation is fast at the early stage and slow at the later stage.The crack propagation of the specimen can be divided into a high-speed expansion phase and a steady-speed expansion phase.The impact speed has the greatest influence on the average crack propagation speed,the second is the notch length,and the least is the bedding angle.The crack propagation speed increases with the increase of impact speed,and the growth gradually becomes gentle,and decreases with the increase of notch length.If the influence of the bedding angle is ignored,the two-factor prediction model of the impact speed and notch length on the average crack propagation speed can be obtained.It is found that the greater the impact speed,the shorter the crack initiation time.But the impact speed has little effect on the crack propagation path.The bedding angle has a greater effect on the crack propagation path.Moreover,the crack propagation path is more curved due to the crack expansion along the beddings when the bedding angle is 22.5°,45.0° and 67.5°.