## 3 Field Test Analysis and Delay Adjustment Under Vibration Control
### Vibration Wave Arrival Time Sequence Analysis for Single Monitoring Point and Delay Adjustment  
The monitoring point arrival time sequence was quantitatively analyzed using the method described in Section 2.2. The complete arrival duration was segmented into consecutive 10 ms intervals, dividing the 3600 ms period into 360 discrete time windows ([0,10), [10,20), \(\ldots\), [3590,3600]). Each of the 338 blast hole arrivals was assigned to its corresponding interval, enabling statistical analysis of the number of arrivals in each time interval. Figure 9 presents the arrival wave counts per interval across monitoring points. Analysis revealed significant wave clustering between 2000-2500 ms, with monitoring point B1 recording up to five simultaneous arrivals during the [2100,2110] interval (Figure 9). This phenomenon directly correlated with the local velocity peak visible in Figure 8b. The source locations of these five waves relative to B1 are shown in Figure 10. The observed spindle-shaped waveform (Figure 8b) emerges from distinct temporal patterns: the initial  
Figure 8: Vibration curves at monitoring point B1. (**a**) Single-hole measured curve. (**b**) Multi-hole measured and predicted curves. 0-1300 ms period typically contains \(\leq\) 2 simultaneous arrivals, while the middle-late phase (1300-3100 ms) regularly features \(\geq\) 3 overlapping waves. The proposed initiation sequence adjustment method achieves vibration reduction through the precise temporal separation of wave arrivals. For monitoring point B1, the implementation protocol involves (1) programmatic identification of critical clustering periods (\(\geq\)4 simultaneous arrivals), (2) application of a progressive delay strategy with 50 ms (1/2T) increments starting from the second hole in each cluster, and (3) determination of a benchmark delay parameter from the final hole's adjustment. This active control method is based on the principle of time separation. Not only can it effectively reduce the superposition probability of vibration waves, but can also realize the temporal dispersion of blasting vibration energy and reduce vibration by adjusting the detonation timing. Figure 10: Blast hole locations with simultaneous wave arrivals. Figure 9: Statistics of wave arrival counts at each monitoring point during different time periods. For example, the four vibration waves arriving simultaneously at monitoring point B1 correspond to blast holes #109, #114, #112, and #115 (this sequence represents the order of arrival times and requires adjustment accordingly). The initial detonation times are designed as 1800 ms, 1840 ms, 1820 ms, and 1840 ms, respectively. The adjusted detonation times are 1800 ms, 1890 ms, 1920 ms, and 1990 ms, with each subsequent hole detonation time increased by 150 ms. This adjustment maintains the relative delay times between subsequent holes while shifting their vibration curves backward by 150 ms. Using the same method, five vibration waves arriving simultaneously at the monitoring point are separated, where the last vibration wave to be adjusted corresponded to hole #163. Figure 11 illustrates the number of wave arrivals at monitoring point B1 within each time period after the adjustment. It can be observed that the maximum number of simultaneous wave arrivals at the monitoring point is reduced to three. The reconstructed single-hole vibration curves are superimposed according to the adjusted arrival times to obtain the predicted multi-hole vibration curve, which is then compared with the pre-adjustment predicted vibration curve, as shown in Figure 12. The fixed time intervals for the arrival times of blast holes #109 and #163 start at 1800 ms and 2120 ms, respectively. To separate the four and five simultaneous wave arrivals, additional delays of 150 ms and 200 ms were applied. Given the single-hole vibration curve length of 200 ms, the predicted vibration curve within the range of 1800 ms to 2670 ms is extracted.