The similarity simulation experiment on hydraulic blasting stress wave propagation and coal broken mechanism was conducted in this study.The super dynamic strain measurement system was used to collect strain produced in coal seam.The propagation and attenuation of hydraulic blasting stress wave in coal was studied.The damage area and crack shape were comprehensively evaluated.The coal broken mechanism of hydraulic blasting was studied.The blasting effects of water and air that was non-coupling medium were analyzed comparatively,which proved the advantages of hydraulic fracturing.The results showed that coal body was broken in the means of plastic compression destruction first,forming a pulverizing zone around the blast hole with a radius of about 1.5 times of the radius of the blast hole;then was broken in the means of brittle stretch destruction,forming a wide range of fracture zone with a radius of about 13 times of the radius of the blast hole;and finally stress wave was attenuated as seismic waves,causing the coal physical point of elastic vibration and forming the blasting loose area.%开展了水压爆破爆炸应力波传播及破煤机理实验研究,采用超动态应变测试系统对模拟煤体中产生的爆炸应变进行了采集分析,研究了水压爆破爆炸应力波在煤体中的传播,根据损伤破坏区域、裂纹形态等爆破效果,研究了水压爆破破煤机理,通过分析水、空气2种炮孔不耦合介质对煤体爆破作用的影响,对比证明了水压爆破煤体致裂效果明显.研究结果表明:煤体首先呈现塑性压缩破坏,在炮孔周围形成粉碎区,粉碎区半径约为炮孔半径的1.5倍;然后呈现脆性拉伸破裂,形成大范围裂隙区,裂隙区半径约为炮孔半径的13倍;最后应力波衰减为地震波,引起煤体质点产生弹性震动,形成爆破松动区.
展开▼
