LI Ping-feng, WANG Xiu-long, YAN Xiao-bing, et al. Effects of burden on rock crushing characteristics
under lateral detonation of cylindrical charges[J]. 2024, 45(5): 1388-1396.
DOI:
LI Ping-feng, WANG Xiu-long, YAN Xiao-bing, et al. Effects of burden on rock crushing characteristics
under lateral detonation of cylindrical charges[J]. 2024, 45(5): 1388-1396.DOI: 10.16285/j.rsm.2023.0933.
Effects of burden on rock crushing characteristics
under lateral detonation of cylindrical charges
To investigate the effects of burden on rock crushing characteristics under lateral detonation of cylindrical charges
we analyzed the stress state at the free surface using the wave theory. Afterward
to simulate the cylindrical charge detonation
the physical experiment of lateral rock fragmentation was conducted using direct copper wire electro-explosion. The evolution process of surface crack network of the specimen was observed using ultra-high-speed camera technology. The impact of cylindrical charge detonation on rock properties was studied by combining the morphology
dimensions
and distribution characteristics of the blasting crater with different burdens. The results demonstrated that the burden is a crucial factor for controlling the fracture mode
morphology of failure zone
and fragment size during rock blasting. As the burden increased
the crack propagation velocity and density gradually decreased
while the range of crack network expanded
and the preferential propagation direction of cracks changed from transverse to circumferential. Furthermore
the experimental results indicated an increasing trend in the short axis of the fracture zone as the burden increased. Through analyzing the stress state at the free surface
the maximum tensile strain criterion was applied to justify this phenomenon. Finally
the relationship between fragment size and energy consumption was established. Our research findings provide a reference for optimizing the design of rock engineering blasting.