Advanced Blasting Technology for Mining

The use of explosives in both open-pit and underground mining is associated with a sudden increase in pressure during the detonation of explosive charges. Explosives are used for destructive impacts on the rock (exploitation), but they also induce vibrations around the detonation site [1,2,3,4]. To minimize the impact of blast vibrations on nearby railway structures, it is recommended to optimize drilling and explosive charge arrangements by controlling charge height and regulating explosive quantities per blast and per segment (Contribution 1). Dudek et al. (Contribution 2) state that quantifying the resource efficiency impact of alternative blast designs and demonstrating operational and environmental trade-offs aligns with practical engineering choices in surface mining by integrating blasting and diesel-fueled equipment emissions into a unified assessment of ramp construction strategies. Paraseismic vibrations that propagate through the rock mass can be a source of adverse impacts, such as damage to structures within and outside the mine, as well as the risk of landslides on the slopes. Xue et al. (Contribution 3) used a laser Doppler measurement method to provide novel, technical support for measuring and analyzing flameproof enclosure failure modes. Iacob et al. (Contribution 4) developed specific algorithms to analyze the spatial distribution of perforations generated by metal fragments on panels located around the detonation site. Pyra and Żołądek (Contribution 5) found that the use of photogrammetry based on unmanned aerial vehicles (UAVs) led to improved safety conditions, including a documented reduction in rockfall by an average of 42% near protected structures. Furthermore, the photogrammetric approach allowed for a ten-fold reduction in the number of images captured and an 80% reduction in model processing time, without compromising mapping accuracy. Another area of interest is the transport of explosives, which requires special procedures. Maranda et al. (Contribution 6) found that sensitizing the matrix directly in the blasthole obviates the need for transporting explosive materials via public roads, a factor that is critical for ensuring transport safety. This work determined the classification of sensitizers, their physicochemical properties, and their interactions with the emulsion matrix. A further study by Nachlik and Pytlik (Contribution 7) investigated laboratory testing of explosives. This testing requires the use of test stands that reflect industrial conditions, and, at the same time, indicate areas for optimization. Nachlik and Pytlik revealed that inter-laboratory comparison tests are crucial for determining the overall level of sensitivity of the tested explosives, and applying sound and light detectors during sensitivity to friction tests may partially eliminate the human factor, resulting in more compliant results.

One of the basic parameters determining the effectiveness of mining with explosives is the correct arrangement of holes in rows. Casale et al. (Contribution 8) revealed that the relationship between row spacing, spacing, and detonation sequence was embedded within the powder factor formula, where these parameters influence fragmentation and displacement outcomes. They develop a simplified method for determining the powder factor that can serve as both a design validation tool and a parameter for estimating the cost of interventions on unstable slopes. With regard to underground mining, for both ore and coal, one area of particular interest is the impact of vibrations on the rock bolt and arch yielding support. Zheng et al. (Contribution 9) employed numerical modeling and discovered that there is a quantitative relationship between the explosion equivalence factor and damage evolution, and determined that a dynamic damage model should be developed for underground excavations. Pei et al. (Contribution 10) confirmed that propagation of blast-induced shock waves in a T-shaped tunnel exhibits consistent patterns across four distinct batches, shaped by reflections and diffractions. To achieve adequate excavation progress, special blasting patterns are developed, which are adapted to ensure appropriate fragmentation of the mined material and to avoid roof collapse in the case of roofs composed of high-strength rocks that accumulate the elastic energy of the rock mass. Liu et al. (Contribution 11) stated that to achieve good pre-cracking in complex stress fields, the direction of the local maximum principal stress must be aligned with the direction of the inter-hole crack. Delayed sandblasting can be used to improve the crack root, allowing cracks to expand and merge in adjacent holes.

Finally, Gautam et al. (Contribution 12) found that roof blasting depends on the nature of local roof falls, results of strata monitoring studies, and the hanging span of roof strata near the line of extraction. In this work, the researchers developed blasting design strategies to promote caving and minimize roof overhang for the continuous miner technology used in the bord and pillar mining method.

The use of explosives in both open-pit and underground mining is widespread [5] and continues to evolve thanks to the availability of materials, their safe use, and the monitoring of their impact on structures, mine workings, and mine supports. Further research at universities and research institutes will be developed and verified under real-world conditions to reduce operating costs while achieving the desired crushing of ore and minimizing the impact on the surrounding environment and rock mass.