Adjustment mechanism of blasting dynamic-static action in the water decoupling chargeAdjustment mechanism of blasting dynamic-static action in the water decoupling charge

Water decoupling charge blasting excels in rock breaking, relying on its uniform pressure transmission and low energy dissipation. The water decoupling coefficients can adjust the contributions of the stress wave and quasi-static pressure. However, the quantitative relationship between the two contributions is unclear, and it is difficult to provide reasonable theoretical support for the design of water decoupling blasting. In this study, a theoretical model of blasting fracturing partitioning is established. The mechanical mechanism and determination method of the optimal decoupling coefficient are obtained. The reliability is verified through model experiments and a field test. The results show that with the increasing of decoupling coefficient, the rock breaking ability of blasting dynamic action decreases, while quasi-static action increases and then decreases. The ability of quasi-static action to wedge into cracks changes due to the spatial adjustment of the blast hole and crushed zone. The quasi-static action plays a leading role in the fracturing range, determining an optimal decoupling coefficient. The optimal water decoupling coefficient is not a fixed value, which can be obtained by the proposed theoretical model. Compared with the theoretical results, the maximum error in the model experiment results is 8.03%, and the error in the field test result is 3.04%.