For the problems of the groove shape and section pre-crack appearing in the back section of bench blasting in Baiyun Obo Iron mine.According to the Livingston blasting funnel theory,the technical parameters of the back holes are adjusted,the hole distance of the back holes are adjusted from 9 m to 7 m,single hole charge from 450 kg to 400 kg.back hole drilling and blasting technology,significantly improve the quality of the blasting,mining section regularity of blasting area back holes.The back holes has reduced damage to the rock mass behind the blasting zone,and vibration cracks are reduced.The pre-fractured and the big lump ratio of the excavation section in the back row are reduced;the big lump ratio at the back of the blast reactor decreased from 20/10000 t to 16/10000 t,annual savings in secondary blasting costs about RMB600 000.Back hole drilling and blasting technique improvement program,while ensuring the orderly and efficient production of mines,the overall efficiency of the mines is improved.It can provide reference for other mines.%针对白云鄂博铁矿采场台阶爆破区后排断面出现凹槽形和断面预裂的问题,依据利文斯顿爆破漏斗理论,调整后排孔的穿爆技术参数,将后排孔的孔距从9 m降到7 m,单孔装药量从450 kg降到400 kg.改进后的后排孔穿爆技术,明显提高爆破质量,爆区后排孔采掘断面规整;后排孔对爆区后方岩体破坏作用降低,振动裂隙减少;爆区后排孔采掘断面预裂缝隙及大块率降低;爆堆后部大块率从20个/万 t降低到16个/万 t,年节省二次爆破费用约60万元.后排孔穿爆技术改进方案,在保证矿山生产有序高效进行的同时提高了矿山的整体效益,可为其他矿山提供参考.
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