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Accurate prediction of ground vibration caused by blasting has always been a significant issue in the mining industry. Ground vibration caused by blasting is a harmful phenomenon to nearby buildings and should be prevented. In this regard, a new intelligent method for predicting peak particle velocity (PPV) induced by blasting had been developed. Accordingly, 150 sets of data composed of thirteen uncontrollable and controllable indicators are selected as input dependent variables, and the measured PPV is used as the output target for characterizing blast-induced ground vibration. Also, in order to enhance its predictive accuracy, the gray wolf optimization (GWO), whale optimization algorithm (WOA) and Bayesian optimization algorithm (BO) are applied to fine-tune the hyper-parameters of the extreme gradient boosting (XGBoost) model. According to the root mean squared error (RMSE), determination coefficient (R2), the variance accounted for (VAF), and mean absolute error (MAE), the hybrid models GWO-XGBoost, WOA-XGBoost, and BO-XGBoost were verified. Additionally, XGBoost, CatBoost (CatB), Random Forest, and gradient boosting regression (GBR) were also considered and used to compare the multiple hybrid-XGBoost models that have been developed. The values of RMSE, R2, VAF, and MAE obtained from WOA-XGBoost, GWO-XGBoost, and BO-XGBoost models were equal to (3.0538, 0.9757, 97.68, 2.5032), (3.0954, 0.9751, 97.62, 2.5189), and (3.2409, 0.9727, 97.65, 2.5867), respectively. Findings reveal that compared with other machine learning models, the proposed WOA-XGBoost became the most reliable model. These three optimized hybrid models are superior to the GBR model, CatB model, Random Forest model, and the XGBoost model, confirming the ability of the meta-heuristic algorithm to enhance the performance of the PPV model, which can be helpful for mine planners and engineers using advanced supervised machine learning with metaheuristic algorithms for predicting ground vibration caused by explosions.

Research was conducted at the PT. Bukit Asam Air Laya Mine Site. The aim of the blasting activity is to explode the B2-C interburden layer in order to obtain Seam C coal. The drilling pattern used is a staggered pattern with a vertical drilling direction. The actual blasting geometry used is with a burden of 7 m, spacing of 8 m, hole depth of 8 m, stemming of 4 m, and powder column of 4 m. The level of blasting fragmentation for sizes greater than 160 cm based on theoretical calculations is 26.49 %, while the target set by the company for boulder fragmentation is no more than 20%. To reduce the level of fragmentation, changes were made to the actual geometry by conducting studies using the RL Ash, CJ Konya, and ICI Explosive theories. From this study, recommendations for the proposed blasting geometry were obtained with a burden of 6 m, spacing of 9 m, hole depth of 11.66 m, stemming of 5.14 m, and powder column of 6.52 m. With these changes in geometry, fragmentation measuring more than 160 cm was obtained at 17.15%, or it can be said to achieve the fragmentation target of less than 20%.

In this paper, based on the finite element numerical simulation, the influence of uncoupled charge on rock blasting effect under the condition of water and air is studied. The results show that the stress wave propagation speed of the air medium uncoupled charge is faster, and the stress fluctuation is larger in the early stage of blasting. The water medium uncoupled charge is more effective in energy transfer and crack formation. This shows that the decoupling charge of water medium can improve the energy utilization rate of explosives, reduce the vibration caused by excessive crushing, save the amount of explosives, and enhance the effect of blasting crushing.

Pyrotechnic detection has always been one of the critical issues in blasting safety. Due to the complex environment of blasting sites, irregular detonator wire postures, and the differences in object scales, making the detection of pyrotechnics more challenging. To address these challenges, this paper proposes an improved algorithm based on a multi-scale parallel attention mechanism and wavelet-separable convolution, called WA-YOLO. First, we integrate wavelet convolution into depthwise separable convolution and propose a novel convolutional block (WSDConv, Wavelet Separable Depthwise Convolution). This new convolutional block is added to the model’s backbone, improving feature extraction while also lowering computational parameters. Furthermore, we introduce an improved Cross Stage Partial (CSP) structure by combining multi-scale convolutions with a parallel attention mechanism, embedding it into the C2f module of the neck network to improve the model’s ability to detect objects of varying scales in complex backgrounds. To tackle the detection accuracy drop caused by the irregular shapes and varying aspect ratios of detonator wires, the model uses the Wise-IoU loss function. This enhances the model’s generalization and robustness by improving the precision of overlap calculations for bounding boxes. The experimental results show that the improved model achieved an average precision increase of 12.6% on the self-built dataset, particularly with an average precision increase of 8.3% in the detection of detonators. Additionally, the model performance also improved on the VOC2012 dataset, with a recall increase of 1.3% and an average precision increase of 1.6%. These results indicate that the proposed model exhibits strong generalization capabilities, can work effectively across different datasets, and provides an effective solution to the challenges of target detection in blasting environments.

Using the well-known laws of the theory of elasticity and the basic principles of the quasi-static wave hypothesis of the mechanism of destruction of a solid medium by an explosion, methods have been developed for calculating the parameters of drilling and blasting (D&B) for raises advance using the methods of blast-hole and borehole charges. It has been established that the calculating D&B parameters is carried out in the same sequence as when drifting operation. To check the calculating D&B parameters using the new method during raise advance, a numerical simulation of changes in the stress-strain state of a rock mass under the influence of an explosion was carried out. According to the results of numerical simulation, the formation of zones of inelastic deformation in the face of a rising mine working under blast load, uniform grinding of the rock was obtained, which will avoid the release of oversized pieces after the explosion. The developed methodology was tested in the conditions of the “Yuvileina” mine of PJSC “Sukha Balka” during the raise advance of a 1420 m level using a sticked emulsion explosive (EE) Anemix P. Test explosions obtained good results in blasting the face of a raise, uniform crushing of the rock and a high coefficient of use of bore-holes has been established.

This study focuses on the blasting failure of rock-like materials, aiming to investigate the effect of the joint spatial characteristics and explosive parameters. Rock mass blasting is complex, and the influence of factors like lithology, rock structure, and explosive characteristics needs consideration. In similar model tests, concrete casting molds are used to prepare nine groups of joint models with different joint quantities, angles, and distances. Mixed emulsion explosives are used for blasting, and the crack expansion process and blasting fragmentation properties are analyzed. In numerical simulations, ANSYS/LS-DYNA is employed with carefully selected material parameters. The results show that the blasting effect of rock mass first increases and then decreases with joint width, increases with joint number and spacing, and first increases and then decreases with joint inclination angle. The consistency between the similar model tests and simulation results validates the conclusions of this study, providing theoretical support and practical guidance for optimizing the blasting excavation parameters of the jointed rock mass. This research offers a scientific decision-making basis for dynamic adjustments of blast schemes, safety risk pre-control, and construction efficiency optimization in engineering management.

The technical-economic efficiency of rock extraction works depends significantly on the drilling and blasting works as well as the adjacent costs. The cost of the explosive is an important component in these and the generalization of the widespread use of the use of bulk explosives (ANFO) has generated a significant reduction in the cost. Making the explosive close to the place of use in fixed or semi-stationary installations on the quarry stage eliminates the costs related to storage or long-term storage, transport, escort, security. However, installations for the manufacture of ANFO type explosives must consistently produce a simple quality explosive mixture. The quality lies in the participation of the precursors as well as in the degree of homogenization, stability and a good behavior to external stimuli that can lead to sensibility to initiation stimuli or inhibition of sensitivity where the harmful influence of moisture in the raw material or environment must be emphasized. The paper presents tests and results obtained in recent years for such installations used by several companies in Romania performed under the supervision of INSEMEX specialists. These assessments were completed with the certification of explosives manufacturing facilities for the specified operating parameters as well as for explosives.

PT Multi Nitrotama Kimia is one of the largest mining service companies that provide blasting services and sales of explosives in Indonesia. PT Putra Perkasa Abadi Jobsite Borneo Indobara is one of PT Multi Nitrotama Kimia’s customers who is facing challenges in optimizing blasting activities. Currently, blasting activities at PT Putra Perkasa Abadi Jobsite Borneo Indobara are carried out within 500 m of the active slope, so that the blasting distance is optimized. In optimizing the blasting distance, it is necessary to maintain slope conditions (no underbreak / no overbreak) and to consider the vibration of blasting results on the slopes. The line drilling method was chosen for the blasting trial stage. In the observation activity, an analysis of the resulting blasting and fragmentation vibrations was carried out. Precise planning and good control in field operations play an important role in this experimental process. Based on the results of the blasting trial, no damage was found in the area 25 m – 100 m from the blasting location and a 10% - 20% reduction in blasting vibration results (Peak Vector Sum) was obtained when compared between normal blasting designs with controlled blasting designs.

The formation process of blasting craters and blasting fragments is simulated using the continuum-discontinuum element method (CDEM), providing a reference for blasting engineering design. The calculation model of the blasting funnel is established, and the formation and fragmentation effect of the blasting crater under different explosive burial depths and different explosive package masses are numerically simulated. The propagation law of the explosion stress wave and the formation mechanism of the blasting crater are studied, and the relationship between the rock-crushing effect and blasting design parameters is quantitatively evaluated. Comparing the results of numerical simulation with the results of field tests and theoretical calculations indicated that the three are consistent, which proves the accuracy of numerical simulation. The results showed that the area of the blasting crater rises with the increase of explosive package mass and explosive burial depth. Taking the proportion of broken blocks with particle size ranging from 0.01 to 0.1 m as the research object, it can be found that the proportion of broken blocks with an explosive burial depth of 0.62 to 1.12 m is 0.45 to 0.18 times that with an explosive burial depth of 0.5 m. The proportion of broken blocks with an explosive radius of 4 to 12 cm is 1.14 to 3.29 times that with an explosive radius of 2 cm. The quantitative analysis of the blasting effect and blasting design parameters provides guidance for the design of blasting engineering.

PT Multi Nitrotama Kimia is a mining service company engaged in providing blasting services and the largest sales of explosives in Indonesia. PT Pamapersada Nusantara jobsite Kideco Jaya Agung is one of the customers of PT Multi Nitrotama Kimia in the blasting service business unit. On a far more optimal side, the development of commodity price conditions and operational needs is a common concern. From these conditions, one of the best target cost controls for blasting and fragmentation is to make adjustments and improvement to the quality and quantity of the use of bulk products. The high use of bulk products at the Kideco Jaya Agung Jobsite is a particular concern, especially for rocks that require a high powder factor value, thereby increasing blasting operation costs. From this condition, PT Multi Nitrotama Kimia strives to optimize the bottom value of density product emulsion MNK Max70 using chemical improvement from the previous 1.15 gr/cc to 1.05 gr/cc. This improvement has brought good results, where optimization in terms of using bulks product and blasting quality such as fragmentation and Velocity of Detonation (VOD) values are still in accordance with product standards.