齐大山铁矿北采车间系铁路运输,近三年来,成功地应用定量压碴爆破(即适当调整电铲采幅与爆破进尺的关系,在预爆区坡面留一定量的压碴),控制爆堆宽度。结果,不拆道率1983年为72％,1984年为77.1％,1985年1至8月为84.4％;根底大块率由原来的2.3％下降到2.1％;消除了重大砸铲事故。三年来, In the recent three years, the quantitative ballast blasting has been successfully applied in the northern mining workshop of Qidashan Iron Mine (that is, the relationship between the amplitude of electric shovel blasting and the footage of blasting is properly adjusted and a certain amount of ballast is reserved on the slope surface of the pre-blasting zone) Control blast width. As a result, the rate of non-demolition was 72% in 1983, 77.1% in 1984 and 84.4% in January-August 1985; the bulk rate dropped from 2.3% to 2.1%; and major shoveling accidents were eliminated. Three years ago,