关键词: 24 m高台阶爆破 爆破参数 孔内微差

Abstract: With the increase of mining depth in barun mine，two or four groups of steps are overlapped because the temporary slope does not reach the mining boundary.The slope of the lower step is steep and the width of the step operation is narrow，so the largescale rotary drilling machine in this mine can not work safely on the lower platform.In order to speed up the expansion progress and improve the effective operation time of the equipment，the 24 m high bench blasting technology is put forward on two groups of parallel bench.On the spot，the lithology of the high platform step blasting area is analyzed and the ore producing area is divided.According to the different lithology of the blasting area，the blasting parameters，the charge structure in the hole and the millisecond time in the hole are optimized.The field blasting test shows that the application of 24m high bench blasting technology can reduce the time of avoiding blasting by 40%，increase the pure operation rate of drilling equipment by 31%，and reduce the rate of blasting block by 12%.Good application effect has been achieved in the field，which can be widely used.

Key words: 24 m high bench blasting, Blasting parameters, The millisecond initiation in the hole