高地应力下双孔爆破成缝最优孔间距研究  

Study on the most optimistic hole spacing for double-hole blasting under high in-situ stresses

作　　者：李潜 李海波[1,2] 傅帅旸 鞠明和 李晓锋[1,2] LI Qian;LI Haibo;FU Shuaiyang;JU Minghe;LI Xiaofeng(State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;University of Chinese Academy of Sciences,Beijing 100049,China;State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China)

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点室验室,湖北武汉430071 [2]中国科学院大学,北京100049 [3]中国矿业大学深地工程智能建造与健康运维全国重点实验室,江苏徐州221116

出　　处：《岩石力学与工程学报》2025年第3期678-690,共13页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金区域联合基金项目(U22A20239)。

摘　　要：预裂爆破作为一种典型控制爆破技术,广泛应用于基坑、公路边坡和露天及地下矿山等岩体工程开挖。受地应力夹制作用影响,深部预裂爆破需采用小孔径全耦合和小间距装药,影响了施工周期,显著增加了施工成本。该研究旨在通过理论推导和数值分析研究高地应力下双孔爆破最优孔间距与径向不耦合系数的相关关系。首先通过线弹性理论建立考虑应力波叠加效应的双孔预裂爆破模型,确定不同地应力下孔间距和径向不耦合装药系数的最优关系曲线。基于自主开发的OpenFDEM软件,开展不同应力水平和径向不耦合装药下考虑爆破粉碎区和裂隙区扩展的双孔预裂爆破模拟。研究结果表明:应力波叠加效应对裂纹贯通具有促进作用,地应力较低时,低不耦合系数虽会显著促进裂纹延伸,同时也增大裂隙区分岔密度和扩展范围,增加了围岩损伤范围,不利于预裂缝成型;随着地应力增加,应力波叠加效应降低,进一步影响双孔成缝效果,因此所提出的充分考虑高地应力和应力波叠加效应相互作用的最优孔间距推荐取值,对双孔爆破成缝效果有重要参考价值。As a typical contour blasting technique,presplitting blasting is widely used in rock engineering excavation for foundation pits,highway slopes,open-pit and underground mines.Due to the influence of in-situ stress,deep presplitting blasting requires small-diameter fully coupled charges and closely spaced holes,which affects construction timelines and significantly increases costs.This study aims to investigate the correlation between optimal hole spacing and radial decoupling coefficients under high in-situ stress through theoretical derivation and numerical analysis.A double-hole presplitting blasting model is established using linear elastic theory,incorporating the stress wave superposition effect.This model determines the optimal relationship curves for hole spacing and radial decoupling coefficients under different high in-situ stresses.Using the self-developed OpenFDEM software,simulations are conducted to assess the expansion of the blasting fragmentation zone and fracture zone under various stress conditions and radial decoupling charges.The results indicate that the stress wave superposition effect promotes crack penetration.At low stress conditions,a lower decoupling coefficient significantly enhances crack extension.However,it also increases the density and extent of fracture branching.This enlarges the damage zone and hinders the formation of pre-splitting cracks.As in-situ stress increases,the influence of the stress wave superposition effect diminishes.This further affects the pre-splitting cracks formation in double-hole blasting.This paper proposes optimal hole spacing values that fully consider the interaction between high in-situ stress and stress wave superposition effects,providing important references for enhancing pre-splitting cracks formation in double-hole blasting.

关 键 词：爆炸力学 预裂爆破 有限-离散元方法 炮孔间距 双孔成缝 地应力 

分 类 号：O38[理学—流体力学]