The amplification of blasting vibration on rock slopes significantly impacts the accuracy of vibration monitoring and slope safety evaluation. This study investigates the phenomenon through numerical simulation and explores the amplification mechanism based on structural dynamics and vibration mode analysis. The simulation results show that the vibration amplification phenomenon primarily occurs in the vicinity of the bench crest. Influenced by the geometric dimensions of the bench crest and the physical and mechanical parameters of the rock mass, higher peak vibration velocities occur at the bench crest than at the bench toe, due to an increase in platform width, a decrease in bench height, a reduction in the slope ratio and a lower rock mass quality. Conversely, the distribution of the first principal stress exhibits an opposite trend to that of the peak vibration velocity. To improve the accuracy of safety assessments, it is recommended that monitoring points be placed at the bottom line of the bench. The vibration mode analysis further confirms that the amplification effect is predominantly governed by the low-order vibration modes, determined by geometric dimensions and mechanical parameters of the rock mass. The agreement between the mode analysis and numerical simulation results highlights the critical role of low-order vibration modes in controlling the slope's vibration amplification.

The multi-body and discrete-body dynamic analysis of demolished reinforced concrete structures in China is based on the multi-body dynamic equation (symbol, function) and the variable mass collapse dynamic equation, and the comprehensive solution of the equation, including an analytical solution, is obtained. Using close-range photogrammetry and dynamic equation inversion, the plastic dynamic and structural dismantling parameters of damaged reinforced concrete materials are obtained. Based on the similarity criterion of dynamic equations solution, similarity criterion formulas of notch for different collapse modes of Various structures are established. Namely, the similarity criterion curve fitting formula (5), it's another formula (6), empirical formula (7) of single-notch for building toppling, the example modification curve C₄ of similarity criterion of inter-span falling, and the forward. Toppling similarity criterion formula (8) of backward-seated buildings with the single notch, the similarity criterion formula (9) of continuous impact collapse between floors of high-rise buildings, the empirical formula (10) of multi-notch in-situ impact collapse of high-rise buildings, the overturning similarity criterion curve of double-notch buildings in the same direction, and other notch-similarity criterion curve families of building structure collapse, etc. Furthermore, the building collapse rules of the demolition matching table of building structure-collapse mode-notch characteristics are put forward by analogy with 46 demolition examples from its notch similarity criterion curve and example diagram in China. The judgment rules of building collapse are determined when the coordinate points [λ (λ₁, λ_p), η_h (η_r)] of the building structure and the incision are near the top of the similarity criterion curve. The cut size of various demolition methods of different building structures can be easily determined, and dimensionless charts can determine the demolition effects. Therefore, a simple and accurate demolition control of blasting demolition can be realized using the multi-body dynamic incision control demolition technology (MBDC).

The blasting dynamic response of the gas pipeline and surrounding soil during the excavation of the cross passage at the entrance and exit C of Jinding Street Station of Beijing Metro Line 11 was analyzed using the finite software LS-DYNA. The numerical model's accuracy was confirmed by comparing it with blast-induced vibration data from on-site surveys. The study focused on the dynamic response of the buried gas pipeline to tunnel blasting, considering factors such as different cutting hole delay times, single hole charge, and soil properties. The results indicated that the peak particle velocity (PPV) from the numerical model was within 20% of the field test data. The PPV and peak effective stress (PES) of the pipeline were highest at the side back of the explosion source. A linear relationship between PPV values of the surface soil and the pipeline was observed when the horizontal distance from the tunnel center exceeded 3m in the axial direction of the gas pipeline. The PPVs and PESs on the cross-section of the gas pipeline did not change significantly with increasing delay times between cutting holes. Furthermore, increasing the charge of the cutting hole from 0.2 kg to 0.6 kg led to an increase of 0.5~2.5 times in PPVs and 0.5~1.5 times in PESs. The soil type around the gas pipeline also influenced the peak combined vibration velocity and effective stress, with silty clay having the greatest impact, followed by clayey silt, and then miscellaneous soil.

A reasonable blasting construction method is critical to maintaining caverns' stability and water-sealing integrity. In this study, seismic wave detection and acoustic wave detection were conducted within a water-sealed cavern. The HHT signal analysis method was used to process the seismic wave signals generated by blasting, and both Empirical Mode Decomposition (EMD) and Ensemble Empirical Mode Decomposition (EEMD) were applied to compare and reduce signal mode aliasing, improving the accuracy of signal analysis. The marginal spectrum, instantaneous energy spectrum, three-dimensional energy spectrum, and loose zones in surrounding rock were used to evaluate the influence of different blasting schemes on the water-sealed caverns. The results show that the EEMD-Hilbert analysis method effectively mitigates mode aliasing issues caused by traditional EMD decomposition, producing a smoother and more reliable vibration velocity time-history curve. Marginal spectrum analysis of the reconstructed signal reveals that the frequency band of the double-sided wall heading method ranges from 200 to 380 Hz. In contrast, the frequency band of the single-sided wall guide pit method is narrower, concentrated between 110 and 250 Hz, with relatively lower frequency energy in both conditions. The combined instantaneous energy of the double-sided wall guide method is higher than that of the single-sided wall guide method, with 41.67% and 23.73% of the total instantaneous energy concentrated in the first section of the cutting hole for each method, respectively. The instantaneous energy distribution of the single-sided wall guide method is more uniform and lower than that of the double-sided. The range of loosening rings on both sides of the arch waist in the double-sided wall heading method is about 1.0 to 1.2 m. In contrast, the single-sided wall guide pit method measured 0.8 meters and 1.0 to 1.2 meters on the expanding excavation surface and guide tunnel surface, respectively. A joint analysis of the EEMD Hilbert method and acoustic detection indicates that the single-sided wall guide pit method is more suitable for blasting excavation in water-sealed caverns.

To investigate the fracture toughness of natural slate under dynamic loading, dynamic impact tests were conducted on notched semi-circular bending slate specimens by a 50 mm diameter split Hopkinson pressure bar testing system and the crack growth process was recorded by the high-speed cameras. Furthermore, the dynamic fracture toughness and crack propagation rate of slate under different impact pressure and prefabricated crack lengths were studied. The results show that the dynamic fracture toughness of the specimen is positively correlated with the impact pressure and loading rate, and the dynamic fracture toughness first increases and then decreases with the rise of the prefabricated crack length. According to the fitting results, the dynamic fracture toughness of the specimen reaches the maximum value when the prefab crack length is 7.45 mm. The maximum values of dynamic fracture toughness at 0.2, 0.3 and 0.4 MPa were 2.99, 3.57 and 4.14 GPa·m^1/2, respectively. The failure process of the specimen can be divided into five stages: dynamic damage, crack propagation, crack formation, crack propagation, and specimen fracture. The propagation speed of the main crack of the specimen greatly fluctuates, while the prefabricated crack length has little effect on the propagation velocity of the specimen. The study revealed the differences in dynamic fracture behavior of slate specimens under different working conditions.

Measurement acceptance plays a crucial supervisory and guiding role in mining engineering. However, traditional blasting acceptance processes and methods in underground mines are insufficient to meet modern production needs and affect the efficiency and quality of underground mining. To address this issue, the Yanqianshan Iron Mine -213 m level roadway was studied to explore a new measurement and acceptance method based on a high-precision laser SLAM (Simultaneous Localization and Mapping) algorithm. By obtaining point cloud data of the roadway before and after underground mine excavation, the foundation for subsequent data analysis and processing was established. In the data processing phase, methods such as point cloud denoising, ICP (Iterative Closest Point) registration, point cloud segmentation, and slicing were employed to create comprehensive measurement and acceptance processes for underground mining engineering. Point cloud denoising effectively removes noise and enhances data purity and credibility. The ICP registration method ensures precise alignment of point clouds through iterative optimization, maintaining high data consistency. Point cloud segmentation and slicing techniques offer practical solutions for accurately calculating irregular explosion volumes. The research results demonstrate that this high-precision laser SLAM measurement acceptance method improves work quality and efficiency. It ensures construction quality in underground mining and provides critical technical support for optimizing underground blasting designs.

The impact of blasting vibration on surrounding buildings has been widely concerned. Based on the deep hole bench blasting project of Changtan Open-pit Coal Mine, the characteristics of the adjacent 11-story frame-shear structure office building are comprehensively analyzed. After several blasting vibration tests, the distribution characteristics of vibration velocity and main frequency in different directions were analyzed. The significance of elevation difference on vibration velocity in various directions was obtained through single-factor analysis. Finally, based on the dimensional analysis method, a vibration velocity prediction model under the influence of multiple factors was studied, proposed, and applied to the blasting safety charge design. The main conclusions are as follows: with the increase of floors, the primary vibration direction changes from horizontal radial (X) to horizontal tangential (Y), and finally to vertical (Z). In most working conditions, the PPV_x and PPV_y are not more than 0.17 cm/s and 0.213 cm/s, respectively, and the elevation has little influence. The PPV_z is concentrated in 0.05~0.41 cm/s, and the elevation amplification effect is significant in 7~11 layers. The maximum charge per delay, total charge amount, and horizontal distance are substantial for the three-axis PPV_s. The elevation difference is not significant for the PPV_x but significant for the PPV_y and PPV_z. The main vibration frequency is concentrated in 3~12 Hz, and some reach 16~30 Hz. Based on the vibration prediction model for the office building, combined with the blasting safety regulations and the blasting parameters under the most dangerous working conditions, the total charge of the bottom blasting should be within 10 267 kg, and the total charge of the deep hole bench blasting should be between 8268~8883 kg.

Studying the dynamic response and failure mechanism of hazardous substances storage cabinet structures under internal combustible gas explosion loads can minimize the consequences of explosion accidents, reducing casualties and property losses, which holds significant engineering and social value. This study used methane mixed with air as the combustible gas in internal explosion tests conducted within a hazardous substances storage cabinet structure. Tests were performed under four gas cloud conditions: 1 m³, 8 m³, 27 m³ and 78 m³. Typical overpressure and displacement time-history curves from internal explosion were obtained, and the dynamic response was analyzed. The results show that the displacement response of the storage cabinet structure synchronized with the load response. As the overpressure load increased, the displacement of the storage cabinet wall increased accordingly, reaching their peak nearly simultaneously. The results of overpressure and structural response tests indicate that the peak value of the overpressure load measured in the test did not follow the expected trend, as the more extensive gas volume did not consistently result in higher peak overpressure values.

Taking the construction of Shikui Road Station to Labor Park Station of Dalian Metro Line 5 as the background, a delicate blasting design was used to control the influence of interval tunnel construction on adjacent buildings. In order to prevent the risk of settlement of adjacent bridge piles, a deep hole pre-reinforcement method of non-shrinkage double-liquid grouting (WSS) was used on the tunnel face. The blasting parameters of the tunnel face were optimized, and a detailed blasting design was given by combining with the step sequence of the tunnel construction method (step method and CRD method). The right line utilized the step method, while the left employed the CRD method. The upper bench of the step method and the upper left chamber 1 of the CRD method were blasted twice: initial cutting blasting to create an empty surface followed by secondary blasting to reduce vibration. The unit consumption of explosives in the cutting part was 1.87~2.33 kg/m³ and 0.40~0.80 kg/m³ in other sections, with the Ms-15 nonel detonator used for maximum section control. In addition, the blasting vibration attenuation law formula was inverted through blasting vibration monitoring, facilitating a pre-check for safety. Furthermore, a numerical simulation using the SPH method was conducted for cutting blasting near side-piercing bridge piles with a single-stage charge of 0.30 kg. The response of the bridge pile located 5 m from the detonation point and subjected to explosive load was analyzed. The blasting operation in this area had been completed, and the piers were safe and sound, indicating that the construction scheme for the side-crossing bridge pile section was feasible. Additionally, the stress wave propagation in strata and bridge piles was simulated, showing speeds of 3280 to 3590 meters per second in bridge piles, and an average speed of 1620 meters per second in rock and soil layers. The propagation speed in bridge piles was significantly higher than in the weathered and clay layers. The SPH method proved effective for large-scale particle calculations without requiring supercomputing power for explosives and adjacent rocks.

The drilling and blasting method is widely used in tunnel excavation. Typically, smooth blasting can meet the quality formation requirements. However, achieving ideal contour control blasting effects and ensuring the safety and stability of surrounding rock mass are challenging due to limitations in drilling conditions and charging in small section tunnels, especially when encountering adverse geological conditions. This often results in increased costs for subsequent support and lining. To address these issues, on-site blasting tests were conducted based on small-section hydraulic tunnels to explore applying energy-gathering hydraulic blasting technology to improve blasting parameters in poor geological conditions. The main conclusions from analyzing and evaluating the quality of contour excavation using 3D laser scanning technology are as follows: (1) The results indicate that shaped charge blasting can reduce over-excavation and under-excavation by 40.8% and 54.2%, respectively, compared to conventional blasting under the same geological conditions. (2) A comparative analysis of blasting results under different borehole arrangements shows that no boreholes are needed to connect the arch crown and the side wall. Utilizing the shaped charge effect to control can reduce over-excavation at the arch shoulder. (3) In fourth-class surrounding rock mass, including silty mudstone and stratified sandstone, the smoothness of the wall surface is less affected by blasting parameters and is promarily determined by lithology. Moreover, the smoothness of stratified sandstone can be improved by more than 30% compared to silty mudstone. In summary, the reasonable application of shaped charge water pressure blasting technology in small cross-section hydraulic tunnels can improve tunnel wall shaping under smooth blasting conditions.