摘要
针对厚硬顶板导致高矿压、高位钻孔瓦斯抽采效果不佳的问题,通过爆破相似模拟试验与理论分析相结合的研究方法,对普通爆破与切缝药包爆破载荷作用下物模的宏观裂纹分布模式、损伤特征以及应变和应力的演化规律进行分析,对爆破弱化半径进行定量计算.结果表明:模型表面爆破裂纹分布差异显著;使用损伤度(D)及波降率(η)对岩石爆破损伤情况进行定量表征,发现切缝药包爆破比普通爆破造成的有效损伤范围更大;动态应变信号分析表明,切缝方向上应力波波阵面速度更快、强度更高,岩层受到的爆炸动载更强,测点的峰值应变及峰值应力均显著大于普通爆破.理论计算表明切缝药包爆破弱化半径(21.8 m)大于普通爆破(16.5 m),使用切缝药包超前预裂爆破厚硬顶板可以保障巷道稳定性,并且更具经济效益.研究成果为解决厚硬顶板条件下的矿压与上隅角瓦斯综合防治问题具有一定的指导意义.
To address the issue of the high mineral pressure and high level drill holes'poor extraction which were due to the thick and hard roof,a research approach that integrates blasting similarity simulation testing with theoretical analysis was employed.This methodology is utilized to examine the macroscopic distribution pattern of cracks,the characteristics of damage,and the evolution of strain and stress within the target structure under the influence of both conventional blasting and slit packet blasting loads.Additionally,the blast weakening radius was quantitatively assessed.The results indicate significant disparities in the distribution of blasting-induced cracks on the model surfaces.Moreover,the quantitative characterization of rock blasting damage,employing the damage degree(D)and the wave velocity reduction rate(η),highlights that the effective damage range resulting from slotted cartridge blasting surpasses that of ordinary blasting.An analysis of dynamic strain signals reveals that the stress wavefront propagates faster in the slotting direction,exhibiting higher intensity.This,in turn,endows the rock layer with increased resilience against the explosive dynamic load,resulting in significantly greater peak strain and peak stress at the measurement point compared to ordinary blasting.Theoretical calculations further establish that the weakening radius of slotted cartridge blasting,measuring 21.8 meters,exceeds that of ordinary blasting,which stands at 16.5 meters.Consequently,the utilization of slotted cartridge blasting for thick and hard roof not only guarantees roadway stability but also proves to be more economically efficient.The research results have certain guiding significance for solving the problem of integrated prevention and control of mine pressure and upper corner gas under the condition of thick and hard roof.
作者
乔国栋
刘泽功
高魁
周云权
傅师贵
QIAO Guodong;LIU Zegong;GAO Kui;ZHOU Yunquan;FU Shigui(School of Safety Science and Engineering,Anhui University of Science and Technology,Hefei,Anhui 230031,China;Institute of Energy,Hefei Comprehensive National Science Center,Hefei,Anhui 230031,China)
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2024年第2期334-345,376,共13页
Journal of China University of Mining & Technology
基金
国家自然科学基金项目(52074013,52374179)
华能集团总部科技项目能源安全技术专项(HNKJ20-H87)
合肥综合性国家科学中心能源研究院项目(21KZS216)
安徽省高校研究生科学研究项目(YJS20210396)
安徽省自然科学基金项目(2208085ME125)
安徽省高校优秀青年人才支持计划项目(gxyq2022016)。
关键词
超前预裂爆破
切缝药包
厚硬顶板
高位钻孔
矿压防治
瓦斯抽采
pre-blasting
slotted cartridge
thick and hard roofs
high level drilling
mine pressure control
gas extraction
