Study on Reasonable Millisecond Delay Time in Open-pit Mine

Based on a certain open-pit mine, the peak particle velocitys of each simulated points in the situations of four millisecond delay times and energy attenuation law are obtained, by using LS-DYNA to establish finite model with the millisecond delay times 0ms, 25ms, 42ms,60ms, combined with using Matlab to do the energy analysis. The analyzed results show that the energy attenuation rate is the biggest when the millisecond time is 42ms, and combined with attenuation law of the peak particle velocity, it is concluded that not the millisecond time more longer, the effect better. The reasonable millisecond time for the open-pit mine is found from points of the peak particle velocity and the energy, and then reduce the blasting vibration.