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Abstract

Ground vibration is a serious outcome of open pit mine blastings. The effect of the azimuth of measuring point to the blasted block, the effect of
starting point and the direction of blast movement on the vibration of the surrounding area of the blasted block are considered. In Sarcheshmeh
Copper Mine in SE Iran, seismic waves generated by 14 blasts have been recorded by 6-8 digital seismographs with three component seismometers.
Seismic data from vertical, tangential and radial component seismograms
were processed and analyzed in the frequency and time domains.
By the convolution of seismograms related to one single blasthole with
the time series corresponding to two double blastholes we simulated seismograms for two double blastholes with delay time of 25 and 65 msec.
Results of the seismogram simulation were compared with seismic real data recorded by 3-C seismometer from double blastholes. Thereafter, the
accuracy of the method was confirmed. Then, we simulated seismograms related to several multi-row blastholes with various delays between holes
and rows. Quantifying the effect of location and azimuth of the measuring point as well as the direction of blast movement on simulation of
seismograms, the impact of them on the ground vibration was studied. It was shown that the minimum ground vibration is in a direction with the
azimuth of 180-225° with the free surface of the blasted block.

Keywords