In order to study the influence of delay time on bench blasting,a numerical simulation study on precise delay blasting of a double-hole and double-slope bench was carried out by ABAQUS.The main contents of the research include the stress wave propagation law,the development of tensile and compression damage and the vibration effects of the double-hole bench structure with different delays.The results show that the closer to the free surface,the greater the peak stress and peak particle vibration velocity in the rock mass,and the more obvious the damage area.Meanwhile,on the top surface of the bench,with the increase of distance to blast source,the peak particle vibration velocity in Y direction(horizontal) at each measuring point showed a decreasing increasing-decreasing trend.At the same time,the measuring point with the maximum Y direction(horizontal) velocity is located at 150 mm(1.25 times the hole spacing).The peak particle velocity of the Z-direction(vertical) decreases gradually with the increase of distance to blasting source.Besides,with the increase of time delay between holes,the volume of rock damage unit(D>0.6) decreases in a small range and then increases continuously.When the delay time is 60 μs,the vibration velocity reaches the peak value.With the further increase of delay,the damage volume decreases gradually and tends to a stable value.At the same time,the stress of the measuring point between two holes in the rock reaches the peak value when the delay time between the holes is 60 μs,and the vibration velocity at the top of the bench gradually decreases and tends to be stable at 50 μs.Therefore,it can be considered that 60 μs(0.5 ms/m) is the best delay time for this model.