Study on the effect of blasting breaking rock under different stemming condition

To study the blasting and rock-breaking effects of stemming materials and their mechanisms, the friction force tests on various stemming materials were conducted as well as field experiments involving blasting of concrete specimens under different stemming conditions. The internal blasting stress and fragmentation of the specimens after blasting were analyzed, and further discussions on rock blasting damage were conducted through numerical simulations. The results revealed that when stemming materials were used, the internal blasting stress within the rock was higher, and the size of rock fragments after blasting was smaller. Moreover, under stemming conditions, the distribution range of internal blasting stress widened, the stress peak increased, and the extent of rock damage and fragmentation area increased. The sealing performance of stemming materials was closely linked to their frictional resistance and sealing capability. Among the materials studied, polyurethane foam material demonstrated superior stemming effectiveness and convenient usage, making it a promising choice for engineering applications. These research findings provide valuable guidance for blasthole stemming in rock blasting scenarios.