The matching relationship between explosives and rocks is crucial for improving the energy utilization efficiency of explosives, enhancing blasting effectiveness, and reducing costs. Firstly, this study analyzed the energy distribution during drilling and blasting operations. Then, the damage zone calculation model was revised considering the non-ideal detonation characteristics of explosives and the strain rate effect on rocks. And an on-site mixed explosives and rock matching model was then developed based on the control of energy transmission efficiency. Finally, field experiments were conducted to verify the rationality of the new explosive-rock matching method. The results show that the new method is more scientific and reasonable than traditional methods, and can intuitively reflect the blasting fragmentation effect and energy utilization efficiency, by taking account of the non-ideal detonation behavior of mixed explosives and the strain rate effects on rock damage partition. Blasting fragmentation tests under various explosive-rock matching conditions revealed discrepancies with the traditional wave impedance theory. By applying the new explosive-rock matching method, the percentage of fines was significantly reduced, and the boulder yield decreased from 6.7% to below 1%, further validating the method's effectiveness.

The high-pressure equation of state is the basis of studying the failure mechanism of materials and the propagation law of shock waves under explosion or impact loading. The state of rock has a wide range of applications in the numerical calculation of mining, meteorite impact cratering, rock impact protection, etc. Using a two-stage light gas gun and Photon Doppler Velocimeter (PDV), the Hugoniot relationship, high-pressure equation of state and volume strain equation of red sandstone were studied. The lowest and the highest impact pressure generated by the collision were 7.2 GPa and 19.4 GPa, respectively, and the lowest and the highest planar impact velocity were 0.88 km/s and 1.97 km/s, respectively. At the same time, optic probes were used to measure the shock wave velocity of rock samples. However, The Hugoniot-Elastic-Limit (HEL) point of the red sandstone was not found in the free surface velocity profile recorded by the PDV, indicating that the red sandstone was in a near-fluid state within this impact pressure range. Furthermore, the shock wave velocity D and particle velocity u were linearly fit by the least square method, and the Hugoniot parameters of the red sandstone were C₀=3.04 and λ=1.14, respectively. In addition, the relationship between the volumetric strain η and the impact pressure P were obtained by polynomial fitting, which was P=116η-745η²+1845η³, and the nonlinear fitting coefficient was 0.993. The Hugoniot equation of state and bulk strain equation of red sandstone obtained in this work can provide reference data for numerical calculation and engineering application in red sandstone rock blasting, shock protection engineering, and so on.

Field tests in a region of the plateau were carried out to study the “poly device+emulsion explosives” in tunnel surface blasting and to achieve the feasibility of peripheral hole air spacing charge and poly device on the explosives detonation distance. A seamless steel tube was used to simulate the tunnel peripheral hole for two or more sections of “emulsion explosives+poly device” detonation. A martyrdom test was implemented with#2 rock emulsion explosives. The maximum stable detonation and martyrdom distance were obtained through several groups of experiments. The test results show that the maximum stable detonation and martyrdom distance 15 cm length of polymerized explosives and#2 rock emulsion explosives are respectively 230 cm and 115 cm in the seamless steel tube. The maximum stable detonation distance of multi-section polymerized explosives can reach 80 cm. Due to the radial constraints on the detonation wave of the polymerization device, the front end of the conical metal drug mask explosion formed by the polymerization of energy jets significantly increases the axial and upward shockwave energy, which makes it possible to increase the energy of the shockwave. The emulsion explosives in seamless steel pipe detonation distance increased significantly upward shock wave energy, which can be applied to the tunnel perimeter hole, replacing the detonating cord to achieve air spacing charge and enhance the effect of surface blasting, cost savings, and time savings.

To reduce the loss and dilution of ore in Husab Mine, a blasting movement monitoring (BMM) system was introduced and tested in three production blocks with 177 mm diameter drilling holes and a 7.5 m step height. During the field test, 6, 8, and 5 monitoring holes were arranged in each test block. Two displacement monitoring balls were placed in each monitoring hole at a 3.5 m and 9m depth to record the rock body's vertical and horizontal movement after blasting. The results show that the movement of the ore body due to blasting can be detected by BMM, and the average horizontal displacement of the upper ore body of the three test blocks is 6.55 m, 6.97 m, and 9.24 m, respectively. The average horizontal displacement of the lower ore body is 3.2 m, 3.9 m, and 4.0 m, respectively. The average vertical displacement of the upper ore body is 4.1 m, 2.0 m, and 3.2 m, respectively. The average vertical displacement of the bottom ore body is 0.72 m, 0.98 m, and 0.84 m, respectively. The ore body always moves in the direction with the least resistance during blasting. Whether horizontal or vertical displacement, the displacement of the upper ore body is always more significant than that of the lower ore body. In addition to changes in the boundaries between the ore and rock due to horizontal displacement, vertical displacement also has a significant influence on the loss and dilution of ore, and the bottom ore body may also move to the middle or the upper part of the ore body, and vice versa. The blast zone of open pit mines often consists of a variety of rocks, and both horizontal and vertical displacements of the ore body after completing the blast design based on geological information are the leading causes of ore grade reduction. Using the post-blast rock boundaries obtained from the BMM system monitoring to guide the excavation and transportation operations, the average ore dilution rate has been reduced by 1.2%. The average loss rate has been reduced by 1.5%, which can create more than 10 million RMB of economic benefits cumulatively over the entire life of the Husab Uranium Mine. This technology can accurately define the ore-rock boundary after blasts, which is an important technical means to reduce the ore dilution rate, ore loss rate and ore grade classification errors in open pit mines.

Efficient coordination between different processes is crucial in optimizing resource allocation and minimizing energy consumption during blasting operations in open-pit mines. To address these challenges, the theory of blasting sharing control is proposed, which integrates macroscopic ore fragmentation with mesoscopic damage analysis and introduces a novel ore damage model for the shoveling process. By optimizing inter-process connections and considering factors such as wear and depreciation, a comprehensive energy distribution model is developed across drilling, crushing, blasting, shoveling, and transportation processes. Evaluation and control indices are proposed for each process, leading to the establishment of a blasting sharing control model. The results demonstrate that the ore damage model reveals the multi-phase characteristics of rock blasting failure and effectively predicts the crushing energy consumption by regulating fragmentation levels. With a fitting accuracy exceeding 0.8, this model optimizes the crusher operations while reducing energy consumption. Using the blasting sharing control model enables calculation of the optimal solutions for blast parameter design while establishing an optimal comprehensive energy consumption formula under the constraint conditions, thus enabling the accurate adjustment of energy at each link and providing strong support for efficient, safe, and sustainable mine operations.

As tunnels are integral to railways and other transport infrastructures, studying the vibration response and attenuation rule of tunnel blasting for tunnel construction projects is significant. The blasting solutions proposed in this paper are to minimize clear distance in the blasting excavation of a high-speed railway tunnel for the Chongqing-Kunming high-speed railway construction project. A new excavation method was developed to divide the excavation section into alternating blasting on both the left and right sides. Besides, the blasting vibration velocity of the double-line tunnel was monitored. The vibration velocity analysis of the advance tunnel shows that the maximum vibration velocity in the tunnel is mainly caused by cutting hole and vault auxiliary hole blasting, and the radial vibration velocity is the maximum. The vibration velocity of the arch waist of the explosion side wall is 1.3 to 2 times bigger than that of the arch foot on the cross-section, and the ratio caused by the initiation of the cutting hole is relatively small. Meanwhile, the vibration velocity of each point in front of the tunnel face is more significant than that at the relative position behind the vertical section. In contrast, the attenuation rate of the vibration velocity behind is relatively more significant. The research findings have been successfully applied to the engineering practice, and a relevant small clear distance tunnel has been safely connected.

To study the continuous collapse resistance and dynamic response characteristics of the structure after the blasting failure of the local columns of the RC frame building, the deformation and stress adjustment process of the beam-column substructures adjacent to the columns were observed in real-time through an on-site blasting test of the central column of a blasting and demolition project of an 8-storey frame building. The PKPM was used to establish the corresponding building model. Meanwhile, the dynamic response characteristics of the remaining structure under the failure of the central column and the resistance to continuous collapse was calculated by the demolition component method and the demolition component method in SAP 2000. The results show that the theoretical value of strain after the blast failure of the center column is about 260 με using the strain-moment theoretical formula. The dynamic strain measured in the field is about 377 με, and the value calculated by the numerical simulation is about 238 με. The results of the dynamic strain by the three methods are relatively close. The computed value of the vertical displacement at the failure point is 3.2 mm, close to the field displacement of 2.67 mm, and the calculated value of the plastic angle is 0.051°, close to the field angle of 0.05°. The remaining structure experienced a significant dynamic impact at the instant of the central column failure, and the acceleration values along the positive and negative directions are roughly the same, with a maximum value of 3.5 m/s. After the failure of the central column, the load redistribution occurs in the remaining structure, and the vertical load originally borne by the central column is shared by the surrounding columns, resulting in a significant catenary effect on the upper beam body.

Porous sandwich structures are widely used in anti-explosion due to their excellent specific strength and stiffness. However, current explosion research mainly focuses on the failure mechanism of sandwich structures under small equivalent explosion loading. In contrast, the research on energy absorption characteristics of porous sandwich structures under actual large equivalent loading is rarely reported. To better guide the engineering application, ten kinds of sandwich structures with three kinds of sandwich materials (foam aluminum and honeycomb aluminum with 3 mm×10 mm side length) under different sandwich configurations (single-layer and two-layer sandwiches) and different thicknesses of face sheet/middle sheet/rear sheet were designed. The explosion tests with 0.5 kg TNT and 1 kg TNT equivalent explosion loading were respectively carried out on the above sandwich structures, and the overall deformation characteristics of the sandwich structures were analyzed. The effects of sandwich materials, sandwich configurations and other factors on energy absorption were discussed. Results show that both the foam sandwich structure and honeycomb sandwich structure could absorb energy through the large compression deformation of core material under explosion loading, while the deformation uniformity of the honeycomb structures is better. Furthermore, the energy absorption efficiency of the core is both related to its specific compressive strength and strength/stiffness of the face sheet/rear sheet. It is quite necessary to optimize those parameters to ensure that the core material can obtain a maximum compression and give full play to its energy absorption advantage. It is also found that the double-layer sandwich structure is superior to the single-layer sandwich structure on energy absorption and protection performance, which is an effective way to improve the overall energy absorption of the structure.

Rock drilling and blasting inevitably produce blasting vibration effects and hazards. The accurate analysis and prediction of blasting vibrations and effective active control methods are thus of great practical significance. This paper summarises the achievements in the prediction and active control of blast vibration velocities over the past 40 years. In terms of predicting the peak value of the blasting vibration velocity (PPV), empirical model prediction methods are very convenient, but their prediction accuracy and effectiveness are poor. By introducing probability and statistical theory into empirical model prediction methods, the accuracy of PPV predictions can be improved. The fundamental wave superposition prediction method can comprehensively predict the vibration velocity, frequency, and duration. However, this method requires high testing accuracy for fundamental vibration waves, which requires the establishment of a regular calibration and verification mechanism for blasting vibration data acquisition devices in the blasting industry. Artificial intelligence prediction methods can significantly improve the accuracy of PPV predictions and provide new ideas for predicting blasting vibration effects under the influence of multiple factors. However, these methods are all based on massive amounts of real and effective measured data, and a substantial database of vibration testing data samples is currently lacking. Theoretical PPV prediction models and numerical simulation prediction methods have also been proposed. However, the widespread application of these methods in engineering practice is limited owing to the requirements for professional knowledge and numerical simulation technology. In terms of the active control of blasting vibration velocity, reasonable delay time determination methods for reducing the PPV are first discussed based on the superposition interference effect of vibration waveforms. However, the recommended delay time values proposed by most current methods are only suitable for protecting a single target structure. Then, a method for actively changing the delay time to regulate the frequency components of blasting vibration is discussed from the perspective of adjusting the spectral structure of blasting vibration, which can avoid the natural vibration frequency band and reduce blast vibration hazards to buildings (structures). However, this method currently remains at the theoretical level or under model experimental-scale conditions and lacks large-scale on-site application examples for verification. Finally, several key future research directions for the prediction and control of blasting vibrations are discussed.

To study the effect of aluminum powder particle size on the performance of CO₂ phase change explosion exciters, the changes in the thermal decomposition characteristics, safety, temperature resistance, and reaction heat were investigated by the calorimetric method (TG), ignition test, temperature resistance test, and reaction heat test. The results show that the thermal decomposition characteristics of the excitation agent did not change significantly after adding 40、80 and 120 μm aluminum powders. However, the apparent activation energy of the activator was significantly different. The apparent activation energy of the excitation agent containing 40 μm aluminum powder decreased by 52.92 kJ/mol. Still, the apparent activation energy of the excitation agent containing 80 μm and 120 μm aluminum powders increased by 55.21 and 57.53 kJ/mol, respectively. After adding different particle sizes of aluminum powder, each sample can be ignited in the air, and the combustion process is accompanied by white smoke. A-mong them, the excitation agent with 120μm aluminum powder burns more violently than that without aluminum powder and that with 40 and 80μm aluminum powder. The experimental results show that the excitation agents containing different particle sizes of aluminum powder can be excited by the electric primer, but the sample is not completely ignited. When these excitation agents are in a closed environment and under a certain pressure (greater than or equal to 0.2 MPa), they can be reliably ignited without an obvious explosion phenomenon, indicating that their safety is good. After holding at 70℃for 48 h, the overall excitation agent added with aluminum powder did not change significantly, and the temperature index T_s was about 70℃, indicating that its temperature resistance was good. When the mass percentage of aluminum powder with different particle sizes is the same, the increase in reaction heat is about 12%, indicating that the particle size has little effect on the reaction heat of the excitation agents.