摘要
平舒煤业8213工作面辅助进风切顶留巷顶板预裂爆破受原生裂隙影响,爆生裂隙无序扩散、偏离预裂孔连线,预裂缝呈断续、粗糙锯齿状,造成预裂孔两侧岩体咬合难分离、卸压滞后,致使沿空留巷围岩长期处于高应力状态并引发大变形。为改善裂隙岩体预裂爆破切顶效果,采用离散元颗粒膨胀法开展岩体裂隙分布特征参数对预裂爆破成缝效果影响的数值模拟研究,构建了多参耦合的岩体预裂爆破模拟体系与效果量化评价方法,提出了注浆加固与分段封堵炮泥间隔装药协同作用的预裂爆破效果优化控制方法,并通过现场试爆验证该协同控制方案的可行性。研究结果表明:裂隙与预裂爆破孔连线夹角β,裂隙长度L_(f)和间距d是预裂爆破成缝效果的主要影响因素;β从0°变化到90°过程中,原生裂隙辅助成缝作用逐渐转变为阻碍作用,预裂缝由“一”字型或平缓“之”字型的光滑连续状向“X”型不规则粗糙断续状转变;L_(f)的影响作用随着β的增大而增强,预裂缝的光滑性与连续性大幅劣化;随着d增大,原生裂隙负面影响减弱;采用注浆加固与分段封堵炮泥间隔装药措施后,岩体均质性及预裂孔内爆炸能量均衡性均得到显著提升,最终沿炮孔全长形成明显预裂缝,裂隙率达70%。
During roof presplitting blasting for auxiliary air inlet and roof cutting gob-side entry retaining at Pingshu Coal Industry′s 8213 working face,blast-induced fractures exhibit random propagation patterns and deviate from presplitting holes alignment due to the influence of pre-existing fractures.The presplit fractures exhibit discontinuous,rough,and serrated morphologies,resulting in rock masses interlocking that hinder effective separation along the presplitting hole plane and delay pressure relief.Consequently,the surrounding rock of the gob-side entry retaining maintains prolonged high-stress conditions,leading to significant deformations.To enhance roof-cutting effectiveness in fractured rock masses through presplitting blasting,this study employs the discrete element particle expansion method to numerically investigate how characteristic parameters of fracture distribution influence presplit fracturing outcomes.Furthermore,a multi-parameter coupling simulation system for rock mass presplitting blasting and a quantitative evaluation methodology for blast effect were established.Meanwhile,an optimized control strategy was proposed that leverages the synergistic effects of grouting reinforcement,segmented stemming,and decked charge configurations.Field validation tests confirmed the feasibility of this synergistic approach.Key findings reveal three dominant factors governing presplit blasting effectiveness:(1)the intersection angle(β)between natural fractures and the blast hole alignment,(2)fracture length(L_(f)),and(3)fracture spacing(d).As β increases from 0°to 90°,the primary fractures′role transitions progressively from assisting to inhibiting the fracturing process.In contrast,the presplit fractures evolve morphologically from smooth,continuous linear/gentle-zigzag patterns to irregular,rough,and discontinuous X-shaped configurations.The influence of L_(f) intensifies with the increasing intersection angle(β),while the smoothness and continuity of presplit fractures degrade substantially.The detrimental effect of primary fractures diminishes with greater fracture spacing(d).By implementing grouting reinforcement combined with segmented plugging stemming and spaced charging,both rock mass homogeneity and uniformity of explosive energy distribution in presplitting holes are markedly enhanced,ultimately generating distinct presplit fractures along the full blast hole length at a 70%fracture rate.
作者
李育朋
郭丽安
胡盼
郝兵元
王晨龙
赵婷婷
张涛
LI Yu-peng;GUO Li-an;HU Pan;HAO Bing-yuan;WANG Chen-long;ZHAO Ting-ting;ZHANG Tao(Shanxi Pingshu Coal Industry Co.,Ltd.,Shouyang 045400,China;Taiyuan University of Technology,Taiyuan 030024,China;Shanxi Jichangtai Mine Engineering Technology Co.,Ltd.,Taiyuan 030024,China)
出处
《爆破》
北大核心
2026年第1期62-73,224,共13页
Blasting
基金
国家自然科学基金青年项目(12102294)。
关键词
裂隙分布特征
预裂爆破
注浆加固
分段封堵炮泥间隔装药
fracture distribution characteristics
presplitting blasting
grouting reinforcement
stemming deck charging
