Experimental study on the blasting effects of rich-iron ore with different explosives
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摘要:
台湾1为探究炸药类型对铁矿石爆破效果的影响,选用相同药量的三种炸药对铁矿石试样进行爆破试验。对比研究了不同炸药爆炸作用后试样表面裂纹分形维数和碎块块度分布特征,进而对试样的破坏程度和爆破效果进行了定量的对比与评价。同时,从爆炸应力波叠加、能量释放与传递角度,对爆破效果的差异进行了理论分析。研究结果表明:(1)松散装药以及混合装药均会导致爆源相同距离处爆炸应力场分布的均匀性变差;(2)炸药爆热越大、炸药铁矿石波阻抗匹配程度越高,炸药爆炸后释放的能量越大且能量传递效率越高,铁矿石破坏程度越大;(3)爆破工程中炸药选型时,应重点考虑炸药密度、爆热和爆速三个参数,选择与矿(岩)体波阻抗匹配程度高且爆热合适的炸药,使得爆破后产生的大块和小块均较少。
Abstract:taiwan1 In order to investigate the influence of different explosives type on the blasting effects, three kinds of explosives with the same quality were used to carry out blasting test on iron ore samples. The fractal dimension of surface crack and fragment size distribution of specimens were comparatively studied, and then the damage degree and blasting effects of specimens were quantitatively compared and evaluated. At the same time, the differences of blasting effects are analyzed theoretically from the angle of explosion stress wave superposition, energy release and energy transfer. The results show that: (1) Both loose charge and mixed charge will cause the uniformity of the explosion stress field distribution to deteriorate; (2) The greater the explosion heat, the greater the energy released after explosion; the higher the wave impedance matching, the higher the energy transfer efficiency after explosive explosion; (3) In the selection of explosives in blasting engineering, three parameters of explosive including density, explosion heat and detonation velocity should be considered; Explosives with a high degree of wave impedance matching and appropriate explosion heat should be selected so that the bulk and small pieces generated after blasting are less.
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Key words:
- iron ore /
- blastability /
- blasting fragmentation /
- fractal dimension /
- wave impedance /
- explosion heat /
- detonation velocity
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表 1 岩体可爆性分级标准
Table 1. Classification standards of rock blastability
可爆性等级 天然裂隙程度、平均间距及分数 单轴抗压强度及分数 密度及分数 波阻抗及分数 总分数 可爆性描述 裂隙程度 l/m 分数 σc/MPa 分数 ρ/(g•cm-3) 分数 Zr/(Gg•m-2•s-1) 分数 Ⅰ 极度裂隙 <0.10 1 <80 1 <2.50 1 5.0 1 8 易爆 Ⅱ 强烈裂隙 0.30 2 100 2 2.75 2 7.5 2 4 中等可爆 Ⅲ 中等裂隙 0.75 3 140 3 3.00 3 10.0 3 12 难爆 Ⅳ 轻微裂隙 1.25 4 170 4 3.25 4 12.5 4 16 很难爆 Ⅴ 极少裂隙 >1.50 5 >180 5 >3.50 5 15.0 5 20 特别难爆 Table 2. Blastability evaluation result of high-grade iron ore
评价指标 指标值 得分 权重 得分 总分 可爆性等级 l/m 18.8 1.25 4 1.20 4.8 Ⅴ(特别难爆)111 σc/MPa 227.0 5 1.0 5.0 ρ/(g•cm-3) 4.25 5 0.7 3.5 Zr/(Gg•m-2•s-1) 24 1.1 5.5 表 3 炸药参数
Table 3. Explosive parameters
试验 炸药 质量/g 直径/mm 高度/mm 密度/(g•cm-3) 爆热/(kJ•kg-1) 爆速/(km•s-1) 波阻抗/(Gg•m-2•s-1) 匹配系数 A DDNP 1 6 63 0.56 1 811 3.529 1.976 0.082 B DDNP+RDX 1 6 59 0.61 3 494 3.975 2.425 0.100 C 单发雷管 1 6 31 1.13 4 167 5.173 5.845 0.242 表 4 爆破块度分布函数参数
Table 4. Parameters of blasting fragmentation distribution function
试验 炸药 试样 G-G-S分布函数参数 相关系数 x0/mm n A DDNP A-1 268.7 2.87 0.964 8 A-2 275.4 2.92 0.976 7 B DDNP+RDX B-1 253.6 5.95 0.976 0 B-2 249.8 7.22 0.976 3 C 雷管 C-1 230.3 2.60 0.962 3 C-2 224.0 2.54 0.993 3 表 5 爆破块度分布评价指标
Table 5. Evaluation indexes of blasting fragmentation distribution
试验 炸药 试样 d10/mm d50/mm d90/mm d90/d50 dmax/mm 实验 平均 实验 平均 实验 平均 实验 平均 实验 平均 A DDNP A-1 120 123 211 214 259 262 1.23 1.23 269 272 A-2 125 217 266 1.22 275 B DDNP+RDX B-1 172 177 226 226 249 248 1.10 1.09 254 252 B-2 182 227 246 1.08 250 C 雷管 C-1 95 93 176 173 221 218 1.25 1.26 230 227 C-2 90 170 214 1.26 224 -
[1] 王青, 任凤玉. 采矿学[M]. 2版. 冶金工业出版社, 2011: 5-32. [2] ZHANG Y Q, HAO H, LU Y. Anisotropic dynamic damage and fragmentation of rock materials under explosive loading [J]. International Journal of Engineering Science, 2003, 41(9): 917-929. DOI: 10.1016/S0020-7225(02)00378-6. [3] 何天贵, 马建军, 赵东坡. 爆破大块率与爆破主参数之间的函数关系[J]. 武汉科技大学学报(自然科学版), 2005, 28(3): 254-256. DOI: 10.3969/j.issn.1674-3644.2005.03.014.HE T G, MA J J, ZHAO D P. Functional relationship between rate of blasting chunk and major parameters [J]. Journal of Wuhan University of Science and Technology (Natural Science Edition), 2005, 28(3): 254-256. DOI: 10.3969/j.issn.1674-3644.2005.03.014. [4] ZHU Z M, XIE H P, MOHANTY B. Numerical investigation of blasting-induced damage in cylindrical rocks [J]. International Journal of Rock Mechanics and Mining Sciences, 2008, 45(2): 111-121. DOI: 10.1016/j.ijrmms.2007.04.012. [5] 冯春, 李世海, 郑炳旭, 等. 基于连续-非连续单元方法的露天矿三维台阶爆破全过程数值模拟[J]. 工程力学, 2019, 39(2): 024201. DOI: 10.11883/bzycj-2017-0393.FENG C, LI S H, ZHENG B X, et al. Numerical simulation on complete process of three-dimensional bench blasting in an open-pit mine based on CDEM [J]. Explosion and Shock Waves, 2019, 39(2): 024201. DOI: 10.11883/bzycj-2017-0393. [6] TAYLOR L M, PREECE D S. Simulation of blasting induced rock motion using spherical element models [J]. Engineering Computations, 1992, 9(2): 243-252. DOI: 10.1108/eb023863. [7] 钮强, 熊代余. 炸药岩石波阻抗匹配的试验研究[J]. 有色金属, 1988, 40(4): 13-17.NIU Q, XIONG D Y. A study of acoustic impedance match between explosives and rocks [J]. Nonferrous Metals, 1988, 40(4): 13-17. [8] 杨小林. 炸药岩石阻抗匹配与爆炸应力、块度的试验研究[J]. 煤炭学报, 1991, 16(1): 89-96.YANG X L. Study of blasting stress, size and matched impedance between explosive and rock [J]. Journal of China Coal Society, 1991, 16(1): 89-96. [9] FARAMARZI F, MANSOURI H, EBRAHIMI F M A. A rock engineering systems based model to predict rock fragmentation by blasting [J]. International Journal of Rock Mechanics and Mining Sciences, 2013, 60: 82-94. DOI: 10.1016/j.ijrmms.2012.12.045. [10] 潘鹏飞, 孙厚广, 韩忠和, 等. 利用钻孔注水试验测试爆区周边岩体损伤场的可行性研究[J]. 岩土力学, 2016, 37(S1): 323-328. DOI: 10.16285/j.rsm.2016.S1.043.PAN P F, SUN H G, HAN Z H, et al. Feasibility study about testing rock damage distribution surrounding blasting area by water seepage in borehole [J]. Rock and Soil Mechanics, 2016, 37(S1): 323-328. DOI: 10.16285/j.rsm.2016.S1.043. [11] 任凤玉, 王文杰, 韩智勇. 无底柱分段崩落法扇形炮孔爆破机理研究与应用[J]. 东北大学学报(自然科学版), 2006, 27(11): 1267-1270. DOI: 10.3321/j.issn: 1005-3026.2006.11.023.REN F Y, WANG W J, HAN Z Y. The blasting mechanism of fan-patterned holes and its application in sublevel caving[J]. Journal of Northeastern University (Natural Science), 2006, 27(11): 1267-1270. DOI: 10.3321/j.issn: 1005-3026.2006.11.023. [12] 谭卓英, 张建国. 露天深孔爆破大块率与爆破参数之间的关系研究[J]. 爆破, 1999, 16(4): 15-20.TAN Z Y, ZHANG J G. Study on the relationships between boulder yield (BY) and Borehole blasting parameters in open pits [J]. Blasting, 1999, 16(4): 15-20. [13] 王新民, 赵彬, 王贤来, 等. 基于BP神经网络的凿岩爆破参数优选[J]. 中南大学学报(自然科学版), 2009, 40(5): 1411-1416.WANG X M, ZHAO B, WANG X L, et al. Optimization of drilling and blasting parameters based on back-propagation neural network [J]. Journal of Central South University (Science and Technology), 2009, 40(5): 1411-1416. [14] 刘慧, 冯叔瑜. 炸药单耗对爆破块度分布影响的理论探讨[J]. 工程力学, 1997, 17(4): 359-362.LIU H, FENG S Y. Theoretical research of the effect on the blasting fragmentation distribution from the explosive specific charge [J]. Explosion and Shock Waves, 1997, 17(4): 359-362. [15] 蔡建德, 郑炳旭, 汪旭光, 等. 多种规格石料开采块度预测与爆破控制技术研究[J]. 岩石力学与工程学报, 2012, 31(7): 1462-1468. DOI: 10.3969/j.issn.1000-6915.2012.07.020.CAI J D, ZHENG B X, WANG X G, et al. Research on blasting control technique and block size prediction of different dimensions stones [J]. Chinese Journal of Rock Mechanics and Engineering, 2012, 31(7): 1462-1468. DOI: 10.3969/j.issn.1000-6915.2012.07.020. [16] 葛树高. 矿岩可爆性评价与合理炸药单耗的确定[J]. 有色金属, 1995, 47(2): 11-15.GE S G. Estimation of rock blastibility and determination of adaptive explosive consumption [J]. Nonferrous Metals, 1995, 47(2): 11-15. [17] 谢和平. 分形-岩石力学导论[M]. 北京: 科学出版社, 2005. [18] 杨仁树, 许鹏. 爆炸作用下介质损伤破坏的分形研究[J]. 煤炭学报, 2017, 42(12): 3065-3071.YANG R S, XU P. Fractal study of media damage under blasting loading [J]. Journal of China Coal Society, 2017, 42(12): 3065-3071. [19] 测试AAAAAAAtest BBBBB [20] 赵安平, 冯春, 郭汝坤, 等. 节理特性对应力波传播及爆破效果的影响规律研究[J]. 岩石力学与工程学报, 2018, 37(9): 2027-2036. DOI: 10.13722/j.cnki.jrme.2018.0270.ZHAO A P, FENG C, GUO R K, et al. Effect of joints on blasting and stress wave propagation [J]. Chinese Journal of Rock Mechanics and Engineering, 2018, 37(9): 2027-2036. DOI: 10.13722/j.cnki.jrme.2018.0270. [21] 冷振东, 卢文波, 范勇, 等. 侧向起爆条件下的爆炸能量分布及其对破岩效果的影响[J]. 工程力学, 2017, 37(4): 661-669. DOI: 10.11883/1001-1455(2017)04-0661-09.LENG Z D, LU W B, FAN Y, et al. Explosion energy distribution by side initiation and its effects on rock fragmentation [J]. Explosion and Shock Waves, 2017, 37(4): 661-669. DOI: 10.11883/1001-1455(2017)04-0661-09.