JU Ming-he, TAO Ze-jun, YU Li-yuan, et al. Damage and fracture characteristics of hard rocks caused by hysterisis and repeated impacts of steel particles[J]. 2024, 45(4): 1242-1255.
JU Ming-he, TAO Ze-jun, YU Li-yuan, et al. Damage and fracture characteristics of hard rocks caused by hysterisis and repeated impacts of steel particles[J]. 2024, 45(4): 1242-1255.DOI: 10.16285/j.rsm.2023.0515.
The particle impact-assisted rock-breaking technology offers the advantages of high speed and efficiency
demonstrating effective rock-breaking capabilities on hard rock. In a recent study
the author investigated the influence of impact speed of single and double particles
the distance between double particles
and other factors on the surface
three-dimensional and sectional morphology characteristics of high-strength granite. This investigation involved a combination of particle impact testing and discrete element simulation. The study aimed to elucidate the impact parameters’ influence on the changes in impact crater depth
volume
and surface area. Additionally
it examined the distribution of rock-breaking cracks caused by particle impact and evaluated the effectiveness of hysterisis double-particle impact rock-breaking from the perspective of energy absorption rate. The results revealed a positive correlation between impact crater depth and impact velocity. Moreover
as the distance between particles increased
the impact crater underwent morphological changes
becoming separated
with a decrease in volume and an increase in surface area. The simulations indicated that the cracks primarily distributed at the grain boundaries of plagioclase and orthoclase feldspar
with the dominant failure mode being tensile failure. Furthermore
when employing a 5 mm-diameter steel particle on 200 MPa extremely hard granite
the energy absorption curve of hysterisis double-particle impact rock-breaking tended to flatten with increasing impact velocity. Notably
at a particle distance of 8–10 mm and an impact velocity of around 400 m/s
the optimal impact-assisted rock-breaking effect was achieved.