水不耦合装药对深孔预裂爆破应力波能量的影响

Impact of water decoupling charging on the energy of stress waves generated by blast in the process of deep-hole presplit blast in coal-bed

从理论上探讨了在深孔预裂爆破过程中，水不耦合装药对爆轰冲击波的形成和应力波传播规律的影响，利用Matlab编程求解了冲击波初始参数和沿爆破孔径向方向上传播到爆破孔孔壁处的参数；并根据弹性理论提出并求解了正入射情况下爆破孔孔壁表面上的初始冲击压力。在淮南矿业集团丁集矿进行了水不耦合装药深孔预裂爆破实验，并对实验获得的应力波信号进行归一化频谱分析研究。数值计算和现场实验均表明：通过在煤层中进行深孔预裂爆破实验研究发现，当ξ的值为1.5左右时，爆生应力波在10～50 Hz内的分能量最强，同时具有最高的信噪比，这与理论计算结果相吻合。因而，在利用煤层爆破强化增透技术时应将不耦合装药系数设计为1.5左右，同时适当加大爆破药柱的用量，以获得最佳的增透效果。

The impacts of water decoupling charging on the generation and propagation rules of blast -generated shock waves in the process of deep-hole presplitting blast in coal-bed were theoretically discussed in this paper . Taking advantage of Matlab coding method , the initial parameters of shock waves and the parameters of shock waves when they propagated at the wall of blasting hole along the radial direction of blasting hole were solved .And ac-cording to elastic theory , the initial shock pressure on the surface of the wall of blasting hole under the condition of normal incidence was proposed and solved .On-site deep-hole blast experiments with water decoupling charging were conduct at Dingji Coal Mine of Huainan Mining Group , and the normalized spectral analysis was conducted onexperimental stress wave singals .Both on-site experiments and theoretical calculations showed that：the total stress wave energy decreased with the increase of ξ;whenξequalled to 1.5, the stress waves had the largest low-frequen-cy energy component and the highest noise-signal ratio in 10-50Hz frequency band.So, in the practice of increas-ing permeability of coal-bed using deep-hole presplitting blast technology , the coupling coefficient ξshould be de-signed as 1.5, to acquire the best effect of increasing permeability .