BLASTING, Volume. 41, Issue 3, 26(2024)
Dynamic Strain Distribution and Damage Fractal Characteristics of Shale under Radial Uncoupled Charge Blasting
To investigate the impact of a radially uncoupled charge structure on energy transfer and blasting effects of explosives, with the goal of improving energy efficiency and enhancing rock crushing, dinitrodiazophenol was placed in a standard shale specimen with a diameter of 50 mm and a height of 100 mm. A blasting model experiment was conducted using four radial uncoupled charge coefficients -1, 1.5, 2 and 2.5. The strain waveforms in the axial direction of the specimen were analyzed using the ultra-dynamic strain testing system and the complementary set empirical mode decomposition method. The strain behavior of different sections of the specimen was studied, along with the damage fractal dimension and crack development in these sections. The analysis of the explosive energy propagation laws, combined with the strain curve, revealed that the tensile strain peak values were generally higher than the compressive strain peak values. The specimen eventually failed after experiencing significant and repeated tensile and compressive stresses. Importantly, when the radial uncoupling coefficient was 1.5, the energy utilization of the explosive was significantly improved, along with the prolonged action time of the detonating gas. Additionally, the damage fractal dimension of the specimen section with an uncoupled charge structure changed from top to bottom in an “n-type” manner, resulting in the most uniform damage distribution across each section, a fully expanded crack area, and the best blasting effect.
Get Citation
Copy Citation Text
YANG Guo-liang, ZOU Ze-hua, ZHANG He, LI Feng. Dynamic Strain Distribution and Damage Fractal Characteristics of Shale under Radial Uncoupled Charge Blasting[J]. BLASTING, 2024, 41(3): 26
Category:
Received: Aug. 16, 2022
Accepted: Dec. 20, 2024
Published Online: Dec. 20, 2024
The Author Email: Ze-hua ZOU (zouzh_cumtb@163.com)