Due to certain geological characteristics (high thickness, rocky properties), some underground coal mines require the use of explosives. This paper explores the effects of fragmentation of different decks detonated simultaneously in a single borehole with the use of numerical analysis. ANSYS/LS-DYNA code was used for the implementation of the models. The models include an erosion criterion to simulate the cracks generated by the explosion. As expected, the near-borehole area was damaged by compression stresses, while far zones and the free surface of the boundary were subjected to tensile damage. With the increase of the number of decks in the borehole, different changes in the fracture pattern were observed, and the superposition effects of the stress wave became evident, affecting the fragmentation results. The superposition effect is more evident in close distances to the borehole, and its effect attenuates when the distance to the borehole increase.
|Number of pages||9|
|Journal||Geomechanics and Engineering|
|State||Published - Jun 10 2019|
Bibliographical noteFunding Information:
This research is supported by the National Natural Science Foundation of China (No.51674264, No.51574244) and National Key Research and Development Program of China (No.2017YFC0603002, No.2018YFC0604501).
© 2019 Techno-Press, Ltd.
- Coal blasting
- Distributed charges
- Explosion cracks
- Tensile damage
ASJC Scopus subject areas
- Civil and Structural Engineering
- Geotechnical Engineering and Engineering Geology