Research on the method of no-cut-holes blasting for tunnelling

The traditional method of breaking in shot needs many blast holes and much explosive and it causes the small utilization rate of the drill holes, the complex blasting network and the intense blasting quake. In view of this condition,this paper puts out a method of blasting off solid for tunnelling. It increases the distance between the blasting holes to about 2 m and makes the utilization rate of the drill holes reaching or even more than 100%, and reduces the number of sections of the blasting network to 6 or less. On the basis of no cut holes blasting and intensifying the plugging ability,the number of blasting hole has been decreased and the quantity of explosive per each cub. meter of rock deminished and the intensity of the quake evidently lowered.