Influences of in-situ stress on distribution characteristics of rock blasting fragmentation

CAO Zeming; YANG Jianhua; YE Zhiwei; LENG Zhendong; YAO Chi; ZHANG Xiaobo

doi:10.11779/CJGE20230714

Volume 46 Issue 10

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Chinese Journal of Geotechnical Engineering > 2024 > 46(10): 2202-2211. > DOI: 10.11779/CJGE20230714

CAO Zeming, YANG Jianhua, YE Zhiwei, LENG Zhendong, YAO Chi, ZHANG Xiaobo. Influences of in-situ stress on distribution characteristics of rock blasting fragmentation[J]. Chinese Journal of Geotechnical Engineering, 2024, 46(10): 2202-2211. DOI: 10.11779/CJGE20230714

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Influences of in-situ stress on distribution characteristics of rock blasting fragmentation

1.
School of Infrastructure Engineering, Nanchang University, Nanchang 330031, China
2.
Gezhouba Group Explosive Co., Ltd., Chongqing 401121, China

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Received Date: July 26, 2023
Available Online: March 24, 2024

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Abstract

Abstract

During blasting excavation of deep rock masses under high in-situ stress, the rock masses are often difficult to be fully broken, frequently resulting in large fragments. To understand this problem more deeply, the blast-induced rock cracks under various in-situ stress conditions are simulated by using the dynamic finite element method. The fractal dimension theory and the image recognition method are introduced to investigates the influence of in-situ stress on the distribution characteristics of rock blasting fragmentation. The project cases blasted at different depths and in-situ stress levels are also employed to study this problem. The results show that the generation of large fragments during blasting in deep rock masses owes to the inhibiting effect of in-situ stress on the growth of blast-induced cracks in the far field of blastholes, and the orienting effects of the non-hydrostatic in-situ stress on the propagation of blast-induced cracks. As the in-situ stress level increases, average size, the maximum size, nonuniform coefficient and large block rate of rock fragmentation increase significantly. The size of the smaller fragments is little affected by the in-situ stress as these fragments are generated in the vicinity of blastholes and the propagation of blasting cracks in this zone is almost unaffected by the in-situ stress. When the maximum and minimum principal in-situ stresses perpendicular to the blasthole axis differ greatly, it is adverse to rock fragmentation by blasting. In comparison, a better rock fragmentation is achieved when the lateral coefficient of the principal in-situ stresses is about 0.75.
- deep rock engineering,
- blasting,
- in-situ stress,
- blast-induced crack,
- blasting fragmentation

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[1]	谢和平, 李存宝, 高明忠, 等. 深部原位岩石力学构想与初步探索[J]. 岩石力学与工程学报, 2021, 40(2): 217-232. XIE Heping, LI Cunbao, GAO Mingzhong, et al. Conceptualization and preliminary research on deep in situ rock mechanics[J]. Chinese Journal of Rock Mechanics and Engineering, 2021, 40(2): 217-232. (in Chinese)
[2]	HE C L, YANG J, YU Q. Laboratory study on the dynamic response of rock under blast loading with active confining pressure[J]. International Journal of Rock Mechanics and Mining Sciences, 2018, 102: 101-108. doi: 10.1016/j.ijrmms.2018.01.011
[3]	MITCHELL T R, WANG Z, ARAOS M, et al. Experimental and numerical investigation into the fracture patterns induced by blast-loading under unconfined and confined conditions[J]. Rock Mechanics and Rock Engineering, 2023, 56(4): 2433-2455. doi: 10.1007/s00603-022-03195-x
[4]	YANG L Y, YANG A Y, CHEN S Y, et al. Model experimental study on the effects of in situ stresses on pre-splitting blasting damage and strain development[J]. International Journal of Rock Mechanics and Mining Sciences, 2021, 138: 104587. doi: 10.1016/j.ijrmms.2020.104587
[5]	张凤鹏, 闫广亮, 郝琪琪, 等. 单向压应力对砂岩漏斗爆破过程的影响[J]. 东北大学学报(自然科学版), 2021, 42(2): 220-225. ZHANG Fengpeng, YAN Guangliang, HAO Qiqi, et al. Influence of unidirectional compressive stress on the crater blasting of sandstone[J]. Journal of Northeastern University (Natural Science), 2021, 42(2): 220-225. (in Chinese)
[6]	徐颖, 顾柯柯, 葛进进, 等. 装药不耦合系数对初始地应力下岩石爆破裂纹扩展影响的试验研究[J]. 爆破, 2022, 39(4): 1-9. XU Ying, GU Keke, GE Jinjin, et al. Experimental study on effect of charge decoupling coefficient on crack propagation in rock by blasting under initial in-situ stress[J]. Blasting, 2022, 39(4): 1-9. (in Chinese)
[7]	杨建华, 孙文彬, 姚池, 等. 高地应力岩体多孔爆破破岩机制[J]. 爆炸与冲击, 2020, 40(7): 118-127. YANG Jianhua, SUN Wenbin, YAO Chi, et al. Mechanism of rock fragmentation by multi-hole blasting in highly-stressed rock masses[J]. Explosion and Shock Waves, 2020, 40(7): 118-127. (in Chinese)
[8]	HAN H Y, FUKUDA D, XIE J B, et al. Rock dynamic fracture by destress blasting and application in controlling rockbursts in deep underground[J]. Computers and Geotechnics, 2023, 155: 105228. doi: 10.1016/j.compgeo.2022.105228
[9]	CÓRDOVA E, GOTTREUX I, ANANI A, et al. Blasting and preconditioning modelling in underground cave mines under high stress conditions[J]. Journal of the Southern African Institute of Mining and Metallurgy, 2021, 121(2): 71-80.
[10]	高启栋, 卢文波, 冷振东, 等. 岩石爆破中孔内起爆位置对爆炸能量传输的调控作用研究[J]. 岩土工程学报, 2020, 42(11): 2050-2058. doi: 10.11779/CJGE202011010 GAO Qidong, LU Wenbo, LENG Zhendong, et al. Regulating effect of detonator location in blast-holes on transmission of explosion energy in rock blasting[J]. Chinese Journal of Geotechnical Engineering, 2020, 42(11): 2050-2058. (in Chinese) doi: 10.11779/CJGE202011010
[11]	陈榕, 武智勇, 郝冬雪, 等. 高应力下石英砂三轴剪切颗粒破碎演化规律及影响[J]. 岩土工程学报, 2023, 45(8): 1713-1722. CHEN Rong, WU Zhiyong, HAO Dongxue, et al. Evolution rules and effects of particle breakage for quartz sand in triaxial shear tests under high pressures[J]. Chinese Journal of Geotechnical Engineering, 2023, 45(8): 1713-1722. (in Chinese)
[12]	XIE L X, LU W B, ZHANG Q B, et al. Analysis of damage mechanisms and optimization of cut blasting design under high in situ stresses[J]. Tunnelling and Underground Space Technology, 2017, 66: 19-33. doi: 10.1016/j.tust.2017.03.009
[13]	LI X H, ZHU Z M, WANG M, et al. Numerical study on the behavior of blasting in deep rock masses[J]. Tunnelling and Underground Space Technology, 2021, 113: 103968. doi: 10.1016/j.tust.2021.103968
[14]	DEHGHAN BANADAKI M M, MOHANTY B. Numerical simulation of stress wave induced fractures in rock[J]. International Journal of Impact Engineering, 2012, 40: 16-25.
[15]	杨仁树, 肖成龙, 陈程, 等. 基于分形理论不同装药量的爆破动焦散线实验研究[J]. 振动与冲击, 2020, 39(14): 80-86, 93. YANG Renshu, XIAO Chenglong, CHEN Cheng, et al. Experimental study on the blasting dynamic caustics under different charge weight based on the fractal theory[J]. Journal of Vibration and Shock, 2020, 39(14): 80-86, 93. (in Chinese)
[16]	LI X D, LIU K W, YANG J C, et al. Numerical study on blast-induced fragmentation in deep rock mass[J]. International Journal of Impact Engineering, 2022, 170: 104367. doi: 10.1016/j.ijimpeng.2022.104367