Engineering blasting technology is widely applied in mining operations and the construction of buildings and structures, but ground vibrations caused by explosions are a major environmental concern. Peak particle velocity (PPV), frequency, and duration are the primary parameters for blast-induced vibrations, with PPV often used to assess the safety of vibrations. However, frequency attenuation or resonance can lead to building collapse and equipment damage, and relying solely on PPV-based safety standards is insufficient to fully evaluate the safety of blast-induced vibrations. Studying dominant frequency characteristics is crucial for protecting residents, buildings, and equipment. This paper systematically discusses the safety criteria for blast-induced vibrations in various countries, summarizes the classification of dominant frequencies, and points out that there is no clear scope of application for different dominant frequencies, with varying criteria across countries and the absence of a unified standard. Furthermore, the paper analyzes the influence of blasting parameters, explosive types, and geological conditions on dominant frequency, emphasizing the lack of research on other factors such as borehole parameters, free faces, burden, charge structure, and delay time. It also proposes the need for further exploration of factors such as charge coefficients, decoupling coefficients, borehole density coefficients, and specific explosive consumption. For dominant frequency prediction, the machine learning (ML) models proposed in this study have performed excellently in multiple experiments, especially on large-scale datasets. The experimental results show that the correlation coefficients between the predicted values of the ANN and ANFIS models and the measured data are 0.95 and 0.9988, respectively, indicating high prediction accuracy. In addition, the SVM model, when predicting the dominant frequency, generally keeps the relative error within 10%, demonstrating its efficiency and accuracy in predictions. These methods fully validate the prediction capability of the proposed models, highlighting the significant advantages of ML methods in this study and providing strong support for applications in related fields. Although ML methods can significantly improve prediction accuracy, issues such as insufficient sample size and poor generalization ability may lead to reduced prediction accuracy.

The dynamic response law of the vibration cavity effect in the adjacent large-section rectangular coal roadways induced by deep-hole bench blasting vibrations was deeply revealed, and the prediction accuracy of the PPV in the coal roadway was improved. The vibration equations of the coal roadway were derived based on the stress wave propagation theory and the wave-front momentum conservation theorem. Based on coal roadway vibration monitoring data and numerical simulations, the cavity effect and vibration response characteristics of the coal roadway induced by deep-hole bench blasting under varying blast source distances and relative angle conditions were analyzed. A predictive model for PPV of rectangular coal roadway surrounding rock, incorporating the relative angle as one of the key influencing factors, was developed. The results showed that the presence of cavities and changes in the relative angle enhance the asymmetry of the dynamic response of blasting stress waves near the free surfaces of the surrounding rock on each side of the coal roadway, resulting in significant differences. Moreover, as the blasting distance decreases, the cavity effect tends to promote greater PPV differences on each side of the coal roadway. The prediction model exhibited improved accuracy by about 15.6% compared to the traditional Sadovski equation for the face-blasting side of the coal roadway. It demonstrates better adaptability and predictive capability. This research provides a theoretical basis for the dynamic response of adjacent large-section rectangular coal roadways and for preventing dynamic instability failures in open-pit mining.

This study proposes an incremental extreme extraction method based on the waveform characteristics of ground vibration signals obtained from open-pit mines to investigate the distribution and characteristics of ground vibration from deep-hole blasting. Firstly, an incremental extreme extraction method is proposed based on the waveform characteristics of borehole blasting vibration signals in open-pit mines. The proposed method could extract and screen the extreme values of blasting vibration signals and effectively improve the utilization rate of the data. The space vector of particle vibration is introduced to analyze the angle change between the particle velocity vector and the ground surface when the extreme value increases. Finally, the relation between the particle velocity vector and the angle between the ground plane and the increasing extremum position of several sets of measured signals is studied. Based on the statistical analysis, the results show that the particle velocity in the vertical direction has a significant advantage over that of the other two directions, and the angle between the extreme particle velocity vector direction and the ground plane is primarily distributed in the range of 60°~90°. After an unstable distribution of particle velocities in the transition zone, the particle velocities in each direction gradually attain a relatively balanced and stable attenuation condition as the distance increases. This proves the reliability of the proposed vector analysis of particle velocity in understanding the mechanism of rock blasting.

This study systematically analyzes the influence of the charge length-to-diameter ratio and stemming length on the radius and volume of blasting craters in coal and rock blasting crater tests to effectively address the challenge of achieving coal–rock separation in mixed blasting construction. In addition, it examines the energy distribution mechanism of blasting fragmentation and establishes characteristic equations for coal and rock blasting craters. Numerical simulations and blasting tests are conducted to investigate the casting effect of rock benches and the fragmentation characteristics of coal and rock benches under different charge structures. The results indicate that when the ratio of charge length to stemming length exceeds 0.91 and 0.74 for the coal and rock benches, respectively, the utilization rate of explosive energy for rock fragmentation gradually surpasses that for rock throwing. The charging structure is identified as a key factor in achieving coal–rock mixed blasting and separation mining. The explosive energy is effectively utilized with a bottom interval length of 2 m for rock benches and a stemming length ranging from 2.5 to 3 m for coal seams. This configuration raises the connectivity of rock damage cracks, improves the distribution of tensile cracks at the top of the coal seam, and prevents bulging or coal–rock interactions (blasting mixing) at the coal–rock interface. The findings demonstrate that the optimized charging structure effectively achieves separate mining in coal–rock mixed blasting, fulfilling the requirement of avoiding coal–rock mixing during blasting. The research provides valuable mining strategies and technical experience for achieving separate mining in coal–rock mixed blasting in open-pit coal mines and improving the recovery of thin coal seams.

Over-excavation and under-excavation are common issues in tunnel construction using the drilling and blasting method. In some cases, traditional blasting techniques may fail to achieve the desired results. This study systematically investigates the blasting-induced damage effects of C-type cumulative tubes with varying cone angles in different grades of tunnel surrounding rock, aiming to mitigate over-excavation and under-excavation issues while enhancing construction efficiency. First, the working principles of cumulative charges and their mechanisms in rock penetration and fragmentation were systematically analyzed based on the fundamental theory of cumulative blasting. Subsequently, numerical models of single-hole cumulative blasting were developed for both III-level and IV-level surrounding rock conditions to examine the influence of cumulative cone angles on rock crack propagation. Finally, field validation tests were conducted at a tunnel construction site in Chamdo, Tibet. Results showed that a 65° cone angle provided the best performance in III-level rock, while a 55° angle worked best in IV-level rock. Compared to traditional methods, the cumulative charge method increased contour hole spacing by 12 ~ 18% and reduced construction costs by 23.5%. It also cut over-excavation by 58.3% and improved half-hole preservation by 41.7%, ensuring better excavation profile integrity and effectively addressing excavation issues.