“射流+爆轰”微差复合爆破定向造缝机制及其全过程研究  

Research on mechanism of directional slit-making and the whole process of“jet+detonation”micro-differential composite blasting

作　　者：高瑞 赵鸿杰 徐冰琪 于斌[2] 姜泽 GAO Rui;ZHAO Hongjie;XU Bingqi;YU Bin;JIANG Ze(College of Mining Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China)

机构地区：[1]太原理工大学矿业工程学院,山西太原030024 [2]重庆大学煤矿灾害动力学与控制国家重点实验室,重庆400044

出　　处：《岩石力学与工程学报》2025年第1期81-98,共18页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52274135);山西省优秀青年培育项目(202203021224006);山西省重点研发计划项目(202202090301011)。

摘　　要：定向预裂技术有利于岩体的精准垮落及采场应力分布控制,现有煤岩体定向造缝技术主要有定向水射流、定向水力压裂及聚能定向爆破等,存在裂缝尺度小、定向效果差等弊端。提出一种基于“射流+爆轰”的微差复合爆破定向造缝技术,利用射孔弹微秒级定向聚能射流和炸药毫秒级爆破高压劈裂作用,形成定向连续的孔缝融合面,实现精准造缝。介绍了复合爆破技术关键设备和工艺流程;建立聚能射流冲击及二次爆破劈裂的力学模型,分析射流侵彻及炸药二次爆破高压定向劈裂机制,给出射流侵彻及二次爆破过程中裂缝定向扩展长度的理论表达式,揭示复合爆破定向造缝机制。采用LS-DYNA数值模拟软件,建立聚能射流破岩的数值模型,获得聚能射流破岩全过程的孔洞扩展规律及岩石损伤特征,揭示不同时段射流形态、射流速度及孔洞长度的演化规律;在一次射流基础上,建立二次爆破数值模型,明确二次爆破高压劈裂的裂缝扩展全过程,获得裂缝长度、扩展速度及岩石损伤随时间的演化规律;揭示“射流+爆轰”复合爆破定向裂缝扩展的全过程特征。进一步,通过地面混凝土靶试验验证了复合爆破技术定向造缝可行性,并在井下巷道进行了工业性试验。采用钻孔窥视观测井下爆破孔内定向成缝情况,得到孔内91%,89%和61%的定向成缝率。研究成果表明了复合爆破技术定向造缝理论的可行性,为煤矿煤岩体定向控制提供了一种新型技术途径。Directional pre-splitting technology is conducive to the precise caving of rock mass and the control of stope stress distribution.Existing directional fracture technologies mainly include directional water jet,directional hydraulic fracturing and convergence energy blasting,but these methods suffer from small fracture scales and poor directional effects.In this paper,a directional roof slitting by composite blasting(DRSBCB)based on“jet+detonation”was proposed.A continuous directional fracture surface was formed by utilizing the perforating charge's shaped charge jet at the microsecond level and the explosive's high-pressure splitting effect at the millisecond level,achieving precise fracture creation.The key equipment and process flow of the DRSBCB were introduced.The mechanical model of shaped charge jet and secondary blasting was established.The mechanism of the directional jet penetrating rock and the secondary blasting high pressure splitting was obtained.The theoretical calculation formulas of the directional perforation depth of shaped charge jet was provided,and the theoretical expression of the directional crack propagation length during secondary blasting process was given.The mechanism of the DRSBCB was revealed.The numerical model of jet penetrating rock was established by using LS-DYNA numerical simulation software.The jet channel expansion law and rock damage characteristics of the whole penetration process were obtained,and the evolution law of jet morphology,jet velocity and jet channel length in different periods was revealed.Based on the jet penetration model,the numerical model of secondary blasting was established,and the whole fracture propagation process of high pressure splitting in secondary blasting was clarified.The evolution law of crack length,crack propagation speed and rock damage with time was obtained.The characteristic of whole fracture propagation process of the DRSBCB was revealed.Additionally,the feasibility of the DRSBCB was verified through ground concrete target test,and

关 键 词：岩石力学 坚硬顶板 复合爆破 聚能射流 定向造缝 

分 类 号：TU45[建筑科学—岩土工程]