## 3 Field Test Analysis and Delay Adjustment Under Vibration Control
### Vibration Wave Arrival Time Sequence Analysis for Single Monitoring Point and Delay Adjustment
Beyond 2670 ms, the amplitude of the multi-hole vibration curve is unaffected by the adjusted blast holes, and the original vibration curve is shifted backward by 350 ms. Within this time range, the peak positive vibration velocity before adjustment was 2.10 cm\(\cdot\)s\({}^{-1}\), which decreased to 1.86 cm\(\cdot\)s\({}^{-1}\) after adjustment, with a reduction rate of 11.43%. The peak negative vibration velocity before adjustment was \(-\)2.37 cm\(\cdot\)s\({}^{-1}\), and it decreased to \(-\)2.12 cm\(\cdot\)s\({}^{-1}\) after adjustment, with a reduction rate of 10.55%. The root mean square (RMS) value of the vibration wave reflects the energy of the signal and is an important indicator for measuring the signal strength. The RMS values before and after adjustment were 0.84 cm\(\cdot\)s\({}^{-1}\) and 0.69 cm\(\cdot\)s\({}^{-1}\) respectively, representing a decrease of 17.86% compared with the value before adjustment. Figure 11: Wave arrival counts at monitoring point B1 in fixed time intervals after adjustment. The proposed method effectively restricts the number of simultaneous wave arrivals at the monitoring point to three or fewer, thereby significantly reducing the occurrence of high-probability vibration hazards caused by excessive simultaneous wave arrivals. Vibration Wave Arrival Time Sequence Analysis for Multiple Monitoring Points Surrounding the Blast Area and Delay Time Adjustment  
The proposed method provides effective vibration control for a single monitoring point. However, its direct application to multiple monitoring points encounters inherent limitations. These limitations arise from the fact that the vibration wave arrives at each monitoring point at different times in the changing spatiotemporal relationship between different blast source monitoring points, which fundamentally alters the wave interference pattern. As a result, a delay scheme adjusted for a specific monitoring point may destroy the peak-to-valley cancellation effect required at other monitoring points. To address these challenges in an open bench blasting environment, a comprehensive vibration control strategy has been developed. The method begins with a systematic statistical analysis of vibration wave arrival times at all monitoring points. The higher the number of simultaneous wave arrivals at a monitoring point, the higher the probability of vibration exceedance at that time, and the corresponding measurement point location is labeled as a high vibration probability hazard location. The MATLAB program accurately identifies these hidden danger points by detecting time intervals where vibration waves from multiple holes arrive simultaneously, thereby pinpointing the corresponding hole numbers. Through targeted delay-time adjustments, the originally overlapping vibration waves are temporally separated, achieving effective blast vibration mitigation. The study area remained consistent with the aforementioned blast area. Monitoring points were randomly distributed in the 200-400 m annular region, with 20 m spacing ensuring spatial density control. Precise coordinates were obtained through MATLAB programming, and wave arrival time sequences from all holes to each monitoring point were calculated using Equation (2). Based on Equation (3), the MATLAB program is used to lock the maximum value of the number of simultaneous wave arrivals at different  
Figure 12: Comparison of predicted vibration curves before and after adjustment. monitoring points and the corresponding number of the gun holes. Accordingly, a cloud diagram of \"monitoring point position--number of wave arrivals\" is drawn, as shown in Figure 13.  
Figure 13 shows concentrated red zones along the HH1 and HH2 directions, indicating a higher number of simultaneously arriving vibration waves (\(\geq\)5 waves) within specific time windows at these locations.