Safety management plays a vital role in blasting operations, and blasting safety is closely related to the processes of drilling, blasting, loading, transportation, and dumping, with significant interactions among these procedures. However, due to the diverse sources and complex structure of current blasting safety data, the lack of systematic integration poses challenges for on-site personnel to accurately acquire critical safety knowledge under complex working conditions. To address this issue, this study applies a BERT-BiLSTM-CRF-based method for entity recognition in the field of blasting safety management. The BERT pre-trained model is first used to obtain dynamic word embeddings, followed by optimal label sequence tagging using the BiLSTM-CRF model. A knowledge graph covering seven entity types and nine relationship types is constructed and stored using the open-source Neo4j graph database system. Experimental results show that the F₁-score for all entity types exceeds 60%, demonstrating that the proposed model significantly improves entity recognition accuracy compared to traditional models. Based on this, a knowledge graph-based Q&A system for blasting process safety management in open-pit coal mines is developed, enabling rapid querying of domain knowledge and efficient matching of various blasting processes with safety standards. With the support of this Q&A system, on-site engineers can make timely and informed decisions in complex blasting safety management scenarios.

To enhance the accuracy of blasting vibration predictions in an open-pit mine stripping project, a new peak particle velocity (PPV) prediction formula is proposed, incorporating geological elevation differences and slope effects. Based on the principles of dimensional analysis, the traditional Sadovsky formula was modified by introducing the elevation difference (H) and slope coefficient (γ), resulting in a new prediction model (Formula 11). Notably, when H=0, the new formula reverts to the traditional Sadovsky formula, ensuring its reliability. A field vibration monitoring test was conducted in the mine, with 5 monitoring points at elevation differences of 0.222 m, 0.176 m, 0.865 m, 1.617 m, and 2.465 m. Using the TC-4850 blasting vibration meter, vibration data were recorded, and multiple predictions, including the Sadovsky and the newly proposed formula, were fitted using multivariate nonlinear regression. Results show that the proposed formula achieves the highest correlation coefficient (R²=0.905), surpassing other models. Furthermore, the new formula exhibits improved prediction accuracy, with a maximum relative error of 20.85% and an average error of 8.11%, compared to 24.89% and 10.31% for the original Sadovsky formula. By considering the factors of elevation and slope, the proposed prediction formula significantly improves the precision of PPV predictions under complex terrain conditions, providing a scientific basis for blasting vibration control and safety management. Applying the specific scheme and data proves the effectiveness and practicality of the formula.

Since the concept of intelligent blasting was proposed, the on-site mixed explosive vehicles (MEVs) have struggled to meet the evolving demands of the field. Reviewing the development of MEVs abroad reveals that while developed countries have a higher proportion of on-site mixed explosives usage, their levels of automation and intelligence have progressed slowly, with only a handful of civil explosive giants proposing related concepts. In China, to meet the national requirements for intelligent mine construction, some civil explosive enterprises and MEV manufacturers have begun exploring intelligent upgrades and applications for MEVs, achieving notable technological breakthroughs. China Gezhouba Group Explosive Co., Ltd. has developed an intelligent on-site mixed ANFO vehicle featuring precise borehole positioning, automatic blasting design acquisition, one-button charging, and automatic information collection. This article introduces this intelligent ANFO vehicle, detailing its key technologies: high-precision charging metering control systems, intelligent high-precision positioning, and smart loading systems. These advancements offer references for the intelligent development of similar explosive vehicles. The future direction for on-site MEVs is to achieve full intelligence and crewless operation, encompassing capabilities such as unmanned driving, automatic hole targeting, and smart charging. Ultimately, these vehicles aim to integrate seamlessly into the framework of safe and collaborative operations within the mining sector.

Blasting excavation generates transient P-waves that significantly impact tunnel stability. For water-filled diversion tunnels, the dynamic response of the surrounding rock differs from conventional dry tunnels. Most existing analytical studies focus on the steady-state solution and single-lined tunnels, rarely accounting for composite linings or the presence of water. This paper investigates the transient stability response of deep-buried circular composite lining diversion tunnels under transient P-wave disturbances. The fluid within the tunnel is treated as a distinct medium, and the tunnel-lining interface is considered a non-ideal contact surface. By applying Fourier synthesis, wave function expansion, and trapezoidal quadrature formula, an analytical solution is derived. Validation through comparison with existing literature demonstrates the method's effectiveness. The study analyzes the effects of Poisson's ratio of surrounding rock, the non-ideal interface's elastic coefficient, and the disturbance's loading duration on the dynamic stress concentration coefficient. Results indicate that the compressive stress concentrations occur at the roof and floor, while tensile counterpart concentrations appear at the two sidewalls during dynamic disturbance. As Poisson's ratio increases, there is a transition from tensile to compressive stress concentration, with a gradual degree in compressive stress intensity. Poor contact between the rock mass and liner induces oscillations in the stress time-history curve. The dynamic response converges accordingly as the elastic coefficients of an imperfect interface approach those of a perfect interface. With increasing blasting load duration, peak dynamic stress around the roof and floor initially rises, then stabilizes, while stress at the sidewalls initially decreases before leveling off.

To enhance excavation speed in small-section tunnels and address the limitations of oblique and burn cut blasting techniques, a new burn cut blasting method combining long and short straight holes is proposed based on rock blasting theory, stress wave rock breaking theory, and sacrificial blasting theory. This method improves the burn cut blasting approach with equal resistance lines, eliminating the need for empty holes. The blasting parameters and cavity formation process are discussed in detail. Through field tests and the use of different detonators and cutting layouts, the performance of various cutting methods was evaluated in terms of blasting advance, powder factor, and over-excavation and under-excavation. The results show that the proposed burn cut blasting method is not constrained by tunnel cross-sectional area, allowing for independent hole depth design and optimal delay intervals to achieve staged and layered blasting. This technique enhances the role of free surfaces in the cutting process, reducing the minimal resistance line in deep holes. The resulted cavity is a regular rectangular shape, increasing blast hole utilization from 78.5% to 89.3%. Field tests show that, in small-section tunnel blasting, this method increases the advance from 1.6~2.2 m to 2.2~2.5 m compared to traditional inclined-hole cut blasting. Over-excavation was further reduced by 20%~30% when the displacement of surrounding holes remained within 10cm. The proposed cutting method effectively controls costs, improves operational efficiency, and offers both technical and economic advantages with improved blasting outcomes.

The blasting demolition of partial spans in continuous beam bridges frequently entails substantial risks of damage to the adjoining spans. To ensure the effective collapse and fragmentation of the bridge while safeguarding the integrity of adjacent spans, a case study was undertaken focusing on the blasting demolition of a damaged section of a continuous beam bridge in Ankang City. Using ANSYS/LS-DYNA software, numerical simulations were conducted to investigate the impact of water pressure blasting on the upper box girder and evaluate various collapse scenarios for the lower piers. These scenarios included row-by-row inclined collapse, span-by-span collapse, and center-to-both-sides collapse patterns. The optimal blasting scheme was identified by comprehensively evaluating three key parameters: structural fragmentation efficiency, collapse configuration, and induced vibration velocity during demolition. Based on these simulation findings, an optimized blasting design was developed, with subsequent safety verification conducted on the vibration velocities to ensure structural integrity and operational safety. The results demonstrate that implementing water pressure blasting in the upper box girder successfully achieved substantial structural fragmentation while effectively controlling debris dispersion and minimizing potential impacts on neighboring spans. Through a strategic approach involving the conversion of the continuous beam into a supported configuration prior to demolition, coupled with a sequential detonation protocol initiating at the main beams of adjacent spans followed by row-by-row inclined collapse of the lower piers, the proposed scheme successfully achieved controlled bridge demolition. This methodology ensured optimal structural fragmentation while reducing vibration velocities within safe thresholds, effectively protecting adjacent spans. The field implementation results aligned well with the numerical simulations, as evidenced by the controlled collapse process and satisfactory fragmentation patterns observed during the on-site blasting operation. No significant damage was observed in the proximate piers. The peak maximum vibration velocity recorded at the monitoring points in the numerical simulation was 3.58 cm/s, closely aligning with the field-measured value of 3.96 cm/s, demonstrating the simulation results' reliability.

The long burial time, severe corrosion and damage of waste ammunition pose extremely high safety risks. Improper handling or disposal of such unstable ordnance may lead to serious negative impact on society. Taking the disposal work of waste ammunition in Hunan Province as the research object, this paper summarized the main disposal methods, analysed the existing problems, and proposed countermeasures and suggestions to enhance the disposal capabilities. To explore the shortcomings of the current disposal methods, the characteristics of waste ammunition (such as types, age, and conditions) had been analysed by field research and relevant literature. The study reveals that China's waste ammunition disposal system confronts several critical challenges, including: (1) insufficient technical expertise among disposal personnel; (2) inadequate development of specialized storage infrastructure; (3) scarcity of specialized disposal equipment; (4) technological limitations in destruction methodologies; (5) an underdeveloped regulatory framework and institutional mechanisms for disposal operations. To address these challenges, this study proposes a comprehensive set of countermeasures: (1) enhancing specialized personnel training programs to improve technical competencies; (2) upgrading construction standards for dedicated storage facilities to ensure safety and compliance; (3) deploying advanced disposal equipment to increase operational efficiency; (4) developing innovative destruction technologies through targeted research; (5) standardizing disposal mechanisms to establish robust regulatory frameworks. The conclusion indicates that implementing scientific and standardized waste ammunition disposal protocols holds critical importance for mitigating public safety risks and safeguarding civilian lives and property. Future development should prioritize to enhance technological innovation and systematic improve management frameworks. These dual focus areas will collectively elevate operational standards and efficacy in waste ammunition disposal practices.

To mitigate blasting vibration during the excavation of a drainage tunnel located 2.30~3.10 m beneath an existing tunnel, an optimized blasting scheme using millisecond blasting by electronic detonators and a subsection in blasting holes was implemented. The field blasting scheme was initially adjusted based on the conventional blasting situation near the existing tunnel. This involved optimizing hole position parameters and reducing the number of holes. Before the formal blasting in the underpass section, a single-hole blasting test was then conducted near the excavation face to capture the vibration waveform and geological information. Using the linear superposition method, the vibration waveform of various delay intervals was analyzed to select the optimal delay interval. To further improve blasting performance and reduce the vibration of the cut blasting, the first blasting in the cut area was performed by using the subsection blasting in the hole. Field tests and calculations determined that the optimal delay times were 5 ms for the same row of cut holes or spreader holes, 40 ms between rows, and 3 ms for contour holes. The new blasting scheme was implemented and optimized in the field. When the drainage tunnel was excavated at a footage of 1.5 m through the existing tunnel, the maximum vibration of the road surface monitoring point at a distance of 3.10 m directly above was maintained below 4.0 cm/s, ensuring structure safety. Using electronic detonators for precise initiation and sectional blasting successfully controlled site vibration, protected adjacent structures, and provided valuable insights for similar future projects.

In blasting demolition projects of housing buildings, reinforced concrete columns serve as the primary load-bearing structural elements and consequently represent the most frequently targeted components for controlled demolition. The effectiveness of reinforced concrete column demolition through blasting operations plays a pivotal role in ensuring structural instability and controlling the overall collapse mechanism. The evolution of modern reinforced concrete columns, characterized by increased cross-sectional dimensions, higher reinforcement densities, and enhanced material strengths, has significantly elevated the technical complexity of the design of blasting parameters and the protection of flying rocks. The Particle Blasting Method coupled with the Finite Element Method (PBM-FEM) was employed to simulate the dynamic process of explosion impact loading and explosion gas escaping from the borehole through the high-speed motion collision of particles. Full-scale 1∶1 physical model tests were conducted using industrial electronic detonators to accurately replicate the blasting demolition process of high-rise building structural members. The research reveals critical insights into the failure mechanisms and damage propagation characteristics of reinforced concrete columns under controlled demolition conditions. The results show that the explosion gas escapes from the orifice and reduces the utilization rate of explosive energy due to the limited constraint effect of the blocking material on the side of the blast hole. The severity of concrete spalling on the surface of the column is left and right sides > front side > back side. The direction of the minimum resistance line is the main direction to induce concrete damage and throwing.

To explore the influence of ignition position change on overpressure characteristics of methane/air premixed explosion under different equivalence ratios, several tests with varying length-to-diameter and equivalence ratios on the rise rate of peak overpressure and positive pressure duration were carried out through a self-built explosion test system. The main influencing factors affecting the pressurization characteristics of methane/air premixed explosion were analyzed by the dimensional analysis method, and the calculation formulas of rise rate of overpressure peak and positive pressure during methane/air premixed explosion were proposed. The results show that the rise rate of the overpressure peak increases with the increase of the equivalence ratio, and the increase in length-to-diameter ratio makes the rise rate decrease gradually, which is different from the attenuation rate. The positive pressure duration is gradually prolonged with the rise of the length-to-diameter ratio. However, the maximum positive pressure duration corresponds to different equivalence ratios with the length-to-diameter ratio changes. Furthermore, the calculation formulas of the rise rate of overpressure peak and positive pressure duration of methane/air premixed explosion are obtained by the dimensional analysis method, and the feasibility of the formulas is verified by comparing the experimental values with the theoretical values. It was found that methane/air premixed explosion is significantly affected by the ignition position and equivalence ratio, which can provide a reference for the power evaluation and safety control of methane explosions.