As a non-explosive low-disturbance rock breaking technology, carbon dioxide phase transition blasting (CDPTB) is widely used in rock breaking projects such as pressure relief and permeability enhancement in coal mines, open-pit mining, road subgrade excavation, foundation pit excavation, etc. In this paper, the principle and equipment of CDPTB are systematically analyzed, and the characteristics of a reusable fracturing tube and disposable fracturing tube are determined. Different energy calculation methods are analyzed to determine the magnitude or equivalent explosive equivalent of CDPTB. According to the characteristics of impact stress wave and high-pressure gas, the cracking mechanism of CDPTB is proposed. Under the action of medium-impact stress, rock mass will produce multi-point cracking, and high-pressure gas will produce a gas wedge effect in the initial fracture, which determines the comprehensive action path of the stress wave and high-pressure gas. In terms of fracture characteristics, the fractal method is used to evaluate the macroscopic crack and fragment, microscopic fracture and pore characteristics. In terms of vibration characteristics, the attenuation law of CDPTB vibration with distance is statistically analyzed, and the Hilbert–Huang transform method is used to analyze the time–frequency characteristics of CDPTB. This rock breaking technology can be widely used in different projects, and the existing problems and future challenges are put forward.

Deep mining has started in the Huaibei mining area, and the serious threat of high confined water on the floor to the coal seam is gradually increasing. Based on the deep confined water mining project at working face II633 of the Hengyuan coal mine, this paper theoretically analyzes the damage depth of the floor and the risk of water inrush from the floor. The best proportion of grouting materials was quantitatively optimized by indoor experiments, and an industrial field test was conducted to judge the grouting effect. The results show that the failure depth of the bottom plate calculated by theoretical analysis is 31.73 m; a single factor test and a response surface optimization design method determined the best value of each index: water cement ratio 0.8, bentonite 2%, water reducer 0.6%, sodium silicate 2%. The damage depth of the bottom plate after grouting is 18.83~20 m, according to the field monitoring by the strain method. The optimized slurry significantly reduces the damage depth of the floor, ensures the safe and efficient mining of the coal seam above the high–pressure water, and has a high reference value for the safe mining of the coal seam under similar geological conditions.

To address the Rockburst prevention challenges caused by the limitations of roof blasting in deep coal mines, the stress relief mechanism of floor strata was investigated through numerical simulations based on 195 field practices of cross-layer blasting in floor drainage roadways. Three real-time evaluation indices, namely the scalar seismic moment B_m, stress drop B_d and apparent stress B_a per unit charge, were proposed, and a four-level discriminant standard was established. Results show that the scheme effectively intercepts the horizontal stress transmission path by inducing rock mass damage in the floor. Under high tectonic stress conditions, the average vertical and horizontal stresses in key strata decrease by 29.38 and 12.30%, respectively. Simultaneously, the blasting induces the transfer of high-stress concentration zones into the deep surrounding rock, with the maximum offsets of vertical and horizontal stress peaks reaching 5.0 m and 6.0 m, respectively, achieving stress field reconstruction in both intensity and spatial distribution. Cross-validation with seismic wave computed tomography inversion confirms that B_m and B_d indices are highly sensitive in identifying ineffective stress relief events. Field engineering applications significantly reduce the frequency of high-energy microseismic events and stabilize seismic activity, validating the effectiveness of the evaluation system and providing a scientific basis for the quantitative assessment of deep dynamic disasters.