Effect of the detonation method on the stress field distribution and crack propagation of spacer charge blasting
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摘要: 通過模型實驗研究了不同起爆方式對空氣間隔裝藥炮孔兩側損傷分布的影響規律，借助數字圖像相關實驗系統，獲取了全場應變場演化過程及空氣段應變衰減規律，同時借助透射式焦散線實驗系統，探究了起爆方式對預制裂紋動態斷裂行為的影響。實驗結果表明：柱狀藥包炮孔兩側產生的損傷范圍具有顯著的分形特征。采用外側起爆時，空氣段中心兩側均產生損傷，而采用其他起爆方式時，空氣段均未出現損傷。不同起爆方式對空氣段應變場徑向壓應變的影響主要體現在應變大小、衰減速度兩個方面，對軸向拉應變的影響主要體現在時效性、衰減速度兩個方面。不同起爆方式下預制裂紋端部斷裂行為差別較大。采用內側起爆、外側起爆時，裂紋均為水平擴展，呈現典型Ⅰ型裂紋，裂紋起裂主要由拉伸破壞引起，異側起爆時裂紋起裂為Ⅰ?Ⅱ混合型，具體表現為拉?剪破壞。基于數值模擬軟件LS-DYNA，解釋了預制裂紋端部起裂成因，得到了孔壁處應力場分布規律，不同起爆方式對炮孔軸向孔壁處壓力分布影響顯著，裝藥段主要體現在壓力峰值位置和壓力分布形態兩個方面，空氣段主要體現在壓力峰值大小和壓力分布形態兩個方面。Abstract: In this study, a numerical simulation is used to study the effect of initiation methods on the damage distribution on both sides of an air-spaced charge blasthole using lead azide as the explosive and polymethyl methacrylate as the experimental material. The digital image correlation system determines the evolution of the global strain field and the strain attenuation pattern of the air section, and the dynamic caustics experimental system investigates the effect of detonation methods on the dynamic fracture behavior of the precrack. The experimental results show that the damage induced on both sides of the cylindrical charge blasthole has significant fractal properties. The damage degree corresponding to each initiation point of the charge section is the smallest, and the damage degree gradually increases along the detonation path. When it approaches the noninitiating end, the damage degree reduces further due to a decrease in the energy accumulation rate and a portion of the energy dissipation. When the outer detonation method is employed, both sides of the central air section are damaged, but not when the other detonation methods are used. The effect of different initiation methods on the radial compressive strain of the air segment strain field is mostly reflected in the strain size and strain decay rate, whereas the effect on the axial tensile strain is primarily reflected dynamically and in the decay rate. The attenuation coefficient of the strain field is the greatest when the outer detonation is initiated, regardless of whether the strain is radial or axial. The fracture behavior of the precrack end varies considerably depending on the detonation method. When both the inner and outer detonations are used, the crack exhibits a typical I type generated by tensile failure. When antarafacial detonation is used, the crack initiation is mixed I–II, and the specific performance is tensile-shear destruction. The origin of the crack initiation at the end of the precrack is described using LS-DYNA numerical simulation software, and the distribution pattern of the stress field at the blasthole wall is derived. The pressure distribution along the axial hole wall of the blasthole is considerably affected by different detonation methods. The charge section is mainly reflected in the position of the pressure peak and the pressure distribution shape, whereas the air section is primarily reflected in the size of the pressure peak and the pressure distribution shape.
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圖 1 模型方案示意圖. （a）內側起爆試件；（b）外側起爆試件；（c）異側起爆試件
Figure 1. Schematic diagram of the model scheme: (a) inner detonation specimen; (b) outer detonation specimen; (c) antarafacial detonation specimen
圖 2 外側起爆模型示意圖及網格劃分
Figure 2. Schematic diagram and mesh generation of the outer initiation model
圖 3 超高速數字圖像相關實驗系統
Figure 3. Experimental setup of the high-speed digital image correlation
圖 4 試件破壞形態與裂紋分布. （a）試件 I-1;（b）試件 O-1;（c）試件 D-1
Figure 4. Fracture patterns and crack distributions of the specimens: (a) specimen I-1; (b) specimen O-1; (c) specimen D-1
圖 5 裂紋軌跡的計盒維數擬合曲線
Figure 5. Fitting curve of the box-counting dimension of the crack trajectory
圖 6 炮孔孔壁處損傷二值圖及損傷分布.（a）內側起爆;（b）外側起爆;（c）異側起爆
Figure 6. Binary diagram of the damage at the hole wall and the damage distribution law of the blasthole axial hole wall: (a) inner detonation; (b) outer detonation; (c) antarafacial detonation
圖 7 基于數值模擬下炮孔孔壁損傷分布示意圖. （a）內側起爆;（b）外側起爆;（c）異側起爆
Figure 7. Schematic diagram of the blasthole axial wall damage distribution based on numerical simulation: (a) inner detonation; (b) outer detonation; (c) antarafacial detonation
圖 8 爆炸應變場演化過程. （a）應變分量εx的演化過程;（b）應變分量εy的演化過程
Figure 8. Evolution process of the blasting strain field: (a) evolution of strain component εx; (b) evolution of strain component εy
圖 10 應變時程曲線. （a）內側起爆徑向應變；（b）外側起爆徑向應變；（c）異側起爆徑向應變；（d）內側起爆軸向應變；（e）外側起爆軸向應變；（f）異側起爆軸向應變
Figure 10. Strain–time curves: (a) radial strain of inner initiation; (b) radial strain of outer detonation; (c) radial strain of antarafacial detonation; (d) axial strain of inner initiation; (e) axial strain of outer detonation; (f) axial strain of antarafacial detonation
圖 11 應變峰值及其衰減擬合曲線.（a）內側起爆；（b）外側起爆；（c）異側起爆
Figure 11. Strain peaks and their attenuation-fitting curves: (a) inner detonation; (b) outer detonation; (c) antarafacial detonation
圖 12 不同起爆方式下孔壁處壓力分布情況
Figure 12. Pressure distribution at the blasthole wall under different initiation methods
圖 13 數字激光動態焦散線實驗系統
Figure 13. Experimental setup of the digital laser dynamic caustics
圖 14 爆生裂紋擴展的焦散線照片. (a) O-1; (b) I-1; (c) D-1
Figure 14. Caustics images of the blast-induced crack during propagation: (a) O-1; (b) I-1; (c) D-1
圖 15 試件裂紋尖端的動態力學參數隨時間的變化曲線
Figure 15. Dynamic mechanical parameters at the crack tip in the three specimens
圖 16 實際焦散斑示意圖及理論計算結果.（a）O-1, t=40 μs (Model I);（b） I-1, t=30 μs (Model I );（c）KⅡ/KI=0;（d）D-1, t=30 μs（Model I–II）;（e）KⅡ/KI=2.2
Figure 16. Practical caustic speckle diagram and theoretical calculation results: （a）O-1, t=40 μs (Model I);（b） I-1, t=30 μs (Model I);（c）KⅡ/KI=0;（d）D-1, t=30 μs（Model I–II）;（e）KⅡ/KI=2.2
圖 19 圖18所示單元最大主應力隨時間的變化關系. (a)內側起爆; (b)外側起爆; (c)異側起爆
Figure 19. Relationship between maximum principal stress and time of element in Fig.18: (a) inner detonation; (b) outer detonation; (c) antarafacial detonation
圖 20 異側起爆時單元最大主應力隨時間的變化關系. (a)選取單元示意圖; (b)單元H1226387、H1224476、H1222614; (c)單元H1229166、H1227080、H1225015
Figure 20. Relationship between maximum principal stress and time of the unit under antarafacial-initiation: (a) schematic diagram of selected elements; (b) element H1226387, H1224476 and H1222614; (c) element H1229166, H1227080, H1225015
表 1 PMMA試件動態力學參數表
Table 1. Dynamic mechanical parameters of the PMMA specimens
Dynamic elastic modulus,
Ed/(GN·m–2)Dynamic Poisson's ratio, vd Expansion wave velocity, Cp/(m·s–1) Shear wave velocity, Cs/(m·s–1) Optical constants, c/(m·N–1) 6.1 0.31 2320 1260 0.85×10–10 
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表 2 疊氮化鉛爆轟參數表
Table 2. Relevant detonation parameters of lead(II) azide
Volume of gaseous explosion products/(L·kg–1) Explosion heat /
(kJ·kg–1)Temperature of explosion/°C Detonation velocity/(m·s–1) 308 1506 3050 4478
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久色视频表 3 試件斷裂情況統計表
Table 3. Statistical table of specimen fractures
Specimen number l/mm The average of l/mm θ/(°) The average of θ/(°) O-1 65 58.7 0 0 O-2 53 0 O-3 58 0 I-1 10 11 0 0 I-2 12 0 I-3 11 0 D-1 10 9.7 11 11 D-2 9 12 D-3 10 10
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參考文獻
[1] Liu X Y, Gong M, Wu H J, et al. Calculation and practice of blasting parameters of electronic detonator in tunnel under the influence of multi-factor coupling. J Vib Shock, 2021, 40(5): 24 doi: 10.13465/j.cnki.jvs.2021.05.004劉翔宇, 龔敏, 吳昊駿, 等. 多因素耦合影響下隧道電子雷管爆破參數的計算與實踐. 振動與沖擊, 2021, 40(5):24 doi: 10.13465/j.cnki.jvs.2021.05.004 [2] Leng Z D, Sun J S, Lu W B, et al. Mechanism of the in-hole detonation wave interactions in dual initiation with electronic detonators in bench blasting operation. Comput Geotech, 2021, 129: 103873 doi: 10.1016/j.compgeo.2020.103873 [3] Sun P C, Lu W B, Lei Z, et al. Blasting vibration response and control of high rock slopes of thin mountain. Chin J Geotech Eng, 2021, 43(5): 877孫鵬昌, 盧文波, 雷振, 等. 單薄山體巖質高邊坡爆破振動響應分析及安全控制. 巖土工程學報, 2021, 43(5):877 [4] Zhang Z X. Failure of hanging roofs in sublevel caving by shock collision and stress superposition. J Rock Mech Geotech Eng, 2016, 8(6): 886 doi: 10.1016/j.jrmge.2016.06.005 [5] Zhang Z X. Effect of double-primer placement on rock fracture and ore recovery. Int J Rock Mech Min Sci, 2014, 71: 208 doi: 10.1016/j.ijrmms.2014.03.020 [6] Gao Q D, Lu W B, Yan P, et al. Effect of initiation location on distribution and utilization of explosion energy during rock blasting. B Eng Geol Environ, 2019, 78: 3433 doi: 10.1007/s10064-018-1296-4 [7] Yang G L, Yang R S, Jiang L L. Pressure distribution along borehole with axial air-deck charge blasting. Explos Shock Waves, 2012, 32(6): 653 doi: 10.3969/j.issn.1001-1455.2012.06.016楊國梁, 楊仁樹, 姜琳琳. 軸向間隔裝藥爆破沿炮孔的壓力分布. 爆炸與沖擊, 2012, 32(6):653 doi: 10.3969/j.issn.1001-1455.2012.06.016 [8] Liu L, Chen M, Lu W B, et al. Effect of the location of the detonation initiation point for bench blasting. Shock Vib, 2015, 2015: 907310 [9] Leng Z D, Fan Y, Lu W B, et al. Explosion energy transmission and rock-breaking effect of in-hole dual initiation. Chin J Rock Mech Eng, 2019, 38(12): 2451 doi: 10.13722/j.cnki.jrme.2019.0474冷振東, 范勇, 盧文波, 等. 孔內雙點起爆條件下的爆炸能量傳輸與破巖效果分析. 巖石力學與工程學報, 2019, 38(12):2451 doi: 10.13722/j.cnki.jrme.2019.0474 [10] Gao Q D, Jin J, Wang Y Q, et al. Acting law of in-hole initiation position on distribution of blast vibration field. Explos Shock Waves, 2021, 41(10): 138 doi: 10.11883/bzycj-2020-0352高啟棟, 靳軍, 王亞瓊, 等. 孔內起爆位置對爆破振動場分布的影響作用規律. 爆炸與沖擊, 2021, 41(10):138 doi: 10.11883/bzycj-2020-0352 [11] Gao Q D, Lu W B, Leng Z D, et al. Regulating effect of detonator location in blast-holes on transmission of explosion energy in rock blasting. Chin J Geotech Eng, 2020, 42(11): 2050高啟棟, 盧文波, 冷振東, 等. 巖石爆破中孔內起爆位置對爆炸能量傳輸的調控作用研究. 巖土工程學報, 2020, 42(11):2050 [12] Onederra I A, Furtney J K, Sellers E, et al. Modelling blast induced damage from a fully coupled explosive charge. Int J Rock Mech Min Sci, 2013, 58: 73 doi: 10.1016/j.ijrmms.2012.10.004 [13] Zhu Q, Chen M, Zheng B X, et al. Distribution and control technology of rock damage induced by air-deck charge presplitting blasting. Chin J Rock Mech Eng, 2016, 35(Sup 1): 2758朱強, 陳明, 鄭炳旭, 等. 空氣間隔裝藥預裂爆破巖體損傷分布特征及控制技術. 巖石力學與工程學報, 2016, 35(S1): 2758 [14] Qu Y D, Sun C H, Zhang W J, et al. Effect of decking on different hole-wall media in deep-hole blasting. Eng Blasting, 2016, 22(3): 6 doi: 10.3969/j.issn.1006-7051.2016.03.002曲艷東, 孫從煌, 章文姣, 等. 深孔間隔裝藥爆破對不同孔壁介質的影響. 工程爆破, 2016, 22(3):6 doi: 10.3969/j.issn.1006-7051.2016.03.002 [15] Xiang W F, Shu D Q, Zhu C Y. Impacts of detonating mode on blast stress field of linear explosive charge. Chin J Rock Mech Eng, 2005, 24(9): 1624 doi: 10.3321/j.issn:1000-6915.2005.09.026向文飛, 舒大強, 朱傳云. 起爆方式對條形藥包爆炸應力場的影響分析. 巖石力學與工程學報, 2005, 24(9):1624 doi: 10.3321/j.issn:1000-6915.2005.09.026 [16] Starfield A M, Pugliese J M. Compression waves generated in rock by cylindrical explosive charges: A comparison between a computer model and field measurements. Int J Rock Mech Min Sci Geomech Abstr, 1968, 5(1): 65 doi: 10.1016/0148-9062(68)90023-5 [17] Lou X M, Wang Z C, Chen B G, et al. Initial shock pressure analysis for hole wall with air-decked charge. J China Coal Soc, 2017, 42(11): 2875樓曉明, 王振昌, 陳必港, 等. 空氣間隔裝藥孔壁初始沖擊壓力分析. 煤炭學報, 2017, 42(11):2875 [18] Chi E N, Liang K S, Zhao M S. Experimental study on vibration reduction of the hole-bottom air space charging. J China Coal Soc, 2012, 37(6): 944池恩安, 梁開水, 趙明生. 孔底空氣間隔裝藥降振試驗研究. 煤炭學報, 2012, 37(6):944 [19] Wu L, Zhong D W, Lu W B. Study of concrete damage under blast loading of air-decking. Rock Soil Mech, 2009, 30(10): 3109 doi: 10.3969/j.issn.1000-7598.2009.10.037吳亮, 鐘冬望, 盧文波. 空氣間隔裝藥爆炸沖擊荷載作用下混凝土損傷分析. 巖土力學, 2009, 30(10):3109 doi: 10.3969/j.issn.1000-7598.2009.10.037 [20] Liang R, Yu R L, Zhou W H, et al. Application of air interval charge blasting model in mining room. Gold Sci Technol, 2019, 27(3): 358梁瑞, 俞瑞利, 周文海, 等. 空氣間隔裝藥爆破模型在礦房回采中的應用. 黃金科學技術, 2019, 27(3):358 [21] Chen M, Ye Z W, Lu W B, et al. An improved method for calculating the peak explosion pressure on the borehole wall in decoupling charge blasting. Int J Impact Eng, 2020, 146: 103695 doi: 10.1016/j.ijimpeng.2020.103695 [22] Gu W B, Wang Z X, Chen J H, et al. Experimental and theoretical study on influence of different charging structures on blasting vibration energy. Shock Vib, 2015, 2015: 248739 [23] Xu P, Chen C, Guo Y, et al. Experimental study on crack propagation of slit charge blasting in media with vertical bedding plane. J Min Sci Technol, 2019, 4(6): 498許鵬, 陳程, 郭洋, 等. 含垂直層理介質在切縫藥包爆破下裂紋擴展行為的試驗研究. 礦業科學學報, 2019, 4(6):498 [24] Yang R S, Su H. Experimental study on crack propagation with pre-crack under explosion load. J China Coal Soc, 2019, 44(2): 482楊仁樹, 蘇洪. 爆炸荷載下含預裂縫的裂紋擴展實驗研究. 煤炭學報, 2019, 44(2):482 [25] Li Q, Zhang S X, Wan M H, et al. Study on the influence of length-diameter ratio on the mechanical characteristics of cracks at the end of linear charges. J Min Sci Technol, 2019, 4(2): 112 doi: 10.19606/j.cnki.jmst.2019.02.003李清, 張隨喜, 萬明華, 等. 長徑比對束狀炮孔端部裂紋力學特征影響的研究. 礦業科學學報, 2019, 4(2):112 doi: 10.19606/j.cnki.jmst.2019.02.003 [26] Li K X, Li T. Micro-mechanism of bending failure of sandstone under different loading rates. Explos Shock Waves, 2019, 39(4): 108李柯萱, 李鐵. 不同加載速率下砂巖彎曲破壞的細觀機理. 爆炸與沖擊, 2019, 39(4):108 [27] Johnson G R, Holmquist T J. An improved computational constitutive model for brittle materials. AIP Conf Proc, 1994, 309(1): 981 [28] Sun Q, Wang Q Q, Liu G Y, et al. Proximity side blasting based on ultra-high speed DIC method strain field analysis of subway tunnels. J Min Sci Technol, 2018, 3(1): 39 doi: 10.19606/j.cnki.jmst.2018.01.005孫強, 王啟乾, 劉國有, 等. 基于超高速DIC方法的近距側爆破地鐵隧道應變場分析. 礦業科學學報, 2018, 3(1):39 doi: 10.19606/j.cnki.jmst.2018.01.005 [29] Qi F F, Zhang K, Xie J B. Fracturing mechanism of rock-like specimens with different joint densities based on DIC technology. Rock Soil Mech, 2021, 42(6): 1669齊飛飛, 張科, 謝建斌. 基于DIC技術的含不同節理密度類巖石試件破裂機制研究. 巖土力學, 2021, 42(6):1669 [30] Xie H P. Fractal geometry and its application to rock and soil materials. Chin J Geotech Eng, 1992, 14(1): 14 doi: 10.3321/j.issn:1000-4548.1992.01.002謝和平. 分形幾何及其在巖土力學中的應用. 巖土工程學報, 1992, 14(1):14 doi: 10.3321/j.issn:1000-4548.1992.01.002 [31] Wang Y B, Yu B B, Kong J, et al. Methods and devices for evaluation of blasting damage to indoor small quantity rock. J Min Sci Technol, 2020, 5(6): 624 doi: 10.19606/j.cnki.jmst.2020.06.004王雁冰, 于冰冰, 孔驥, 等. 室內小藥量巖石爆破損傷評價方法及裝置. 礦業科學學報, 2020, 5(6):624 doi: 10.19606/j.cnki.jmst.2020.06.004 [32] Zuo J J, Yang R S, Ma X M, et al. Explosion wave and explosion fracture characteristics of cylindrical charges. Int J Rock Mech Min Sci, 2020, 135: 104501 doi: 10.1016/j.ijrmms.2020.104501 -
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