Abstract:

Fa’er tunnel on ShuichengPanxian highway is a tunnel with coal and gas outburst risk. Blasting excavation has to be carried out in the tunnel section, where there is serious gas emission. In the paper, the difference between Nonel blasting and electric detonator blasting is summarized, and the applicability of Nonel blasting and electric detonator blasting in large crosssection tunnel are analyzed. Comparison and contrast is made between the blasting effect of millisecond delay electric detonator and that of high stage millisecond Nonel in terms of tunnel shape, overbreak/shortbreak, mucks, cycling time and safety coefficient, with the blasting excavation of Fa’er tunnel as an example. The results show that the high stage millisecond Nonel blasting is superior to the millisecond delay electric detonator blasting. The paper can provide theoretical reference for blasting excavation of other large crosssection tunnels in the future.

Key words: Fa’er tunnel, tunnel with coal and gas outburst risk, millisecond delay electric detonator for coal mine, blasting, high stage millisecond Nonel