Abstract: Taking the national key promotion of digital detonators as an opportunity， field blasting tests with different high-precision delays were carried out in Heshangqiao Iron Mine. The influence of delay intervals on blasting vibration was compared and analyzed， and the distribution characteristics of blasting fragmentation were analyzed. The results showed that :①the influence of the millisecond time on blasting vibration in the near zone was greater than that on the far zone， and the closer the distance between the measuring point and the explosion zone， the more significant the influence of the millisecond time. ②In the near zone， as the millisecond time increases， the vibration velocity presents a fluctuating change law of "first increase， then decrease， then increase". In the far area， the amplitude of vibration fluctuations was significantly reduced. ③In order to weaken the impact of blasting vibration on the building， different millisecond times should be selected according to the distance between the building and the explosion zone. The suitable millisecond time in the near zone is 16 ms， and it is 40 ms in the far zone.④ The millisecond time has little effect on the distribution of blasting fragmentation，the overall blasting fragmentation presented a positive skew distribution，50% of the blasting fragmentation could be controlled within 70 mm， and 80% of the fragmentation could be controlled within 130 mm.

Key words: blasting vibration, digital detonators, high-precision time delay, regression analysis, image analysis method, blasting fragmentation