摘要
为解决某灰岩建筑石料矿山爆破后小粒径矿石难以与土分离而导致矿石回收率低下的问题,首先基于现场实测数据和数值模拟结果,构建爆破块度与岩体动力损伤关联模型,确定不同岩块粒径对应的动力损伤阈值;其次选用不同空气间隔装药段数和孔网参数开展三维裂隙岩体台阶爆破数值模拟试验,以提高0.3~0.9 m矿石粒径产率为目的,兼顾控制大块率,获取最佳爆破参数;最后,在数值模拟结果的基础上,开展现场爆破试验,优化装药结构和孔网参数。结果表明:灰岩爆破块度尺寸与动力损伤值之间存在负指数函数关系,爆破块度尺寸0.3 m和0.9 m所对应的岩体动力损伤阈值分别为0.793和0.286;仅采用空气间隔装药结构可提高0.3~0.9 m粒径占比,但大块率增幅较大;采用空气间隔装药结构、适当缩小孔网参数可显著提升0.3~0.9 m粒径占比,同时大块率几乎不变;其中采用二段空气间隔装药结构、适当缩小孔网参数,爆破效果最优。矿山现场应用结果表明,0.3~0.9 m矿石粒径占比提高了20.09个百分点,大块率基本不变,炸药单耗降低10.29%。
This study presents a comprehensive approach to solve the problem of low ore recovery caused by the difficulty in separating small-particle size ore from soil after blasting in a limestone building stone mine.Firstly,a correlation model between blasting fragmentation and dynamic damage of rock mass was established based on field measurement data and numerical simulation results,which can determine dynamic damage thresholds corresponding to various rock particle sizes.Secondly,the numerical simulation test of bench blasting in a three-dimensional fractured rock mass was carried out by using different air-decked charging stages and borehole distribution parameters,which can improve the particle size yield of 0.3~0.9 m and control the bulk ratio to obtain the best blasting parameters.Finally,the field blasting tests were conducted to optimize the charge structure and borehole distribution parameters based on numerical simulation results.The results show a negative exponential function relationship between the blasting block size and the dynamic damage value of the limestone.Specifically,the dynamic damage thresholds corresponding to the blasting size of 0.3 m and 0.9 m are 0.793 and 0.286,respectively.Using only an air-decked charging structure alone can increase the particle size ratio of 0.3~0.9 m and significantly raise the bulk rate.Conversely,combining an air-decked charging structure with a reduced hole spacing markedly enhances the particle size ratio of 0.3~0.9 m while maintaining a stable bulk rate.Optimal blasting results are achieved using a two-stage air interval charging structure and a strategic reduction in hole distribution parameters.The field application results show a 20.09 percentage point increase in the 0.3~0.9 m particle size ratio,with the bulk rate remaining virtually unchanged.Additionally,the unit consumption of explosives decreased by 10.29%.
作者
叶海旺
余梦豪
刘聪
陈家涛
周发明
王浩
杨保忠
雷涛
YE Hai-wang;YU Meng-hao;LIU Cong;CHEN Jia-tao;ZHOU Fa-ming;WANG Hao;YANG Bao-zhong;LEI Tao(School of Resources and Environmental Engineering,Wuhan University of Technology,Wuhan 430070,China;Ministry of Education Key Laboratory of Key Non-metallic Mineral Resources Green Utilization,Wuhan University of Technology,Wuhan 430070,China;Hubei Key Laboratory of Mineral Resources Processing and Environment,Wuhan University of Technology,Wuhan 430070,China;Chuzhou Langyashan Mining Engineering Technology Co.,Ltd.,Chuzhou 239000,China)
出处
《爆破》
CSCD
北大核心
2024年第4期84-90,100,共8页
Blasting
基金
国家重点研发计划项目(2020YFC1909602)
湖北省重点研发计划项目(2021BCA152)。
关键词
爆破块度
岩体损伤
空气间隔装药
裂隙岩体
数值模拟
blasting fragments
rock damage
air-decked charge
fractured rock mass
numerical simulation
