摘要
某大型露天矿山在进行310 mm孔径爆破推广试验时,出现较为突出的台阶底部过破碎、上部破碎效果不佳等问题。考虑应力波在岩体中的传播速度与炸药爆轰波速度为同一数量级,开展孔内不同起爆点位对爆炸应力波传播影响的数值模拟。分析表明:孔底起爆在台阶上部产生的应力波峰值最大,但作用时间最短;孔口起爆在下部产生的应力波峰值最大,但作用时间最短;孔中起爆在上下部产生的应力波峰值与作用时间介于二者之间,在中部产生的应力波峰值最大。综合考虑应力波峰值和载荷作用时间,现场试验时将孔内第一发起爆弹上提,使起爆点位于药柱底部和中部之间(距孔底0.5~4.5 m),显著改善了台阶上部破碎效果,验证了分析结论的正确性。
During the promotion test of 310 mm blasthole blasting at a large open‑pit mine,issues such as over‑fragmentation at the bench toe and insufficient breakage in the upper part of the bench were observed.Considering that the propagation velocity of stress waves in rock mass and the blasting wave velocity of explosives are of the same order of magnitude,numerical simulations were conducted to investigate the influence of different detonation point locations within the blast hole on stress wave propagation.The analysis showed that bottom detonation produced the highest stress wave peak in the upper bench with the shortest duration,while top detonation(at the hole collar)produced the highest peak in the lower bench,also with the shortest duration.In‑hole detonation resulted in intermediate stress wave peaks and durations in both upper and lower sections,with the stress wave peak occurring in the middle part of the bench.Based on a comprehensive assessment of stress wave peak values and load duration,field trials were carried out by lifting the first detonator charge to a position between the hole bottom and middle(0.5-4.5 m above the hole bottom).This significantly improved fragmentation in the upper bench and validated the simulation results.
作者
汪伟
彭定潇
兰明
Wang Wei;Peng Dingxiao;Lan Ming(Jiangxi Copper Corporation Limited;Jiangxi Copper Technology Institute Co.,Ltd.;School of Resources,Environment and Safety Engineering,University of South China)
出处
《黄金》
2025年第8期19-23,共5页
Gold
基金
国家自然科学基金青年科学基金项目(12005099)
湖南省教育厅重点项目(19A425)。
关键词
露天开采
台阶爆破
孔内起爆
起爆点位
数值模拟
应力波
现场试验
open‑pit mining
bench blasting
in‑hole detonation
detonation point location
numerical simulation
stress wave
field trial
