Abstract:In order to study the influence of different delay times on underground shallow hole blasting, numerical simulation software LS-DYNA was used to study the operation mode of underground shallow hole blasting with precise delay and hole-by-hole initiation.Based on the research status at home and abroad, five kinds of continuous uncoupled charged with different delay times of 15ms, 20ms, 25ms, 30ms and 35ms were used for shallow-hole blasting. The field fine delay by hole initiation test was carried out. The blasting vibration velocity was collected by blasting vibration tester, and the velocity waveform was explored and analyzed.It was found that the vibration velocity peak at 25ms with delay time decreased by 27%, 8%, 29% and 52%, respectively, compared with the peak velocity at 15ms, 20ms, 30ms and 35ms.The research shows that the delay time is 25ms, and the vibration reduction is the most obvious.Reasonable delay time can effectively reduce the blasting vibration intensity and ensure the safety of surrounding rock masses.