中文摘要：

基于断裂力学理论，对煤体内的准静态应力场和爆生气体驱动裂纹扩展模型进行分析计算，探讨了爆破荷载作用下的裂纹扩展长度。通过模拟煤体爆破试验，对裂纹扩展状况的分析结果表明，煤体爆破裂纹扩展长度与煤体纵波波速和抗压强度成反比，与孔隙率成正比；炮孔堵塞情况下裂纹数量和裂纹长度是不堵塞情况下的1．5—3倍，从而验证了煤体爆破过程中，爆生气体准静态应力作用是爆破裂纹扩展和爆破破碎的主要原因。

英文摘要：

Based on the theory of fracture mechanics, analyzed and calculated the quasi-static stress field in the coal and the model of fracture propagation driven by gases of explosion products. Then proved the length of crack propagation caused by blasting loads. Finally through a blasting test of simulation coal, the results showed that the length of crack propa- gation was inversely proportional to both longitudinal wave velocity and compressive strength, and was directly proportional to porosity. The crack number and the crack length in the case of stemming of blast holes were respectively 1.5 - 3 times to that in the case of unblocked blast holes, verifying that in the process of coal blasting, the quasi-static stress of detonation gas was the main reason in the crack propagation and the blasting broken.