Study on geometric similarity law of steel frame under a far-field explosion load
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摘要: 根据Π定理推导了远距离爆炸荷载作用下钢框架原型结构与缩比模型的几何相似律表达式。基于已有的钢框架子结构爆炸实验,采用AUTODYN建立了钢框架子结构数值模型,验证了流固耦合方法在结构爆炸响应分析中的可靠性。在此基础上,对比了流固耦合方法和解析爆炸边界方法在钢框架远距离爆炸数值模拟中的准确性和计算效率,结果表明,解析爆炸边界方法可以合理地模拟远距离爆炸荷载作用下钢框架的动态响应,且计算效率较高。最后,采用该方法分析了具有不同相似比的两层三跨钢框架结构在远距离爆炸荷载作用下的动态响应及毁伤效应,结果表明:该结构的动态响应和毁伤效应符合几何相似规律。Abstract: According to the Π principle, a similarity law was proposed between the prototype and the scaled-down models of the steel frame under a far-field explosion load. Based on the explosion experiments of steel frame substructures, a numerical model of the substructure was established by AUTODYN to verify the reliability, accuracy, and computational efficiency of the fluid-structure interaction method in the structural explosion response analysis and the analytical blast boundary method by comparing the numerical simulation results with the experiments of the steel frame under the far-field explosion load. The results show that the analytical blast boundary method can reasonably simulate the dynamic response of the steel frame under far-field explosion loads with high computational efficiency. Finally, the dynamic response and damage of a two-story three-span steel frame structure under a far-field explosion load were analyzed by the analytical blast boundary method using different scaling ratios. The results show that when the two-story three-span steel frame is fully scaled according to the geometric similarity ratio, the dynamic displacement responses of the prototype and the scaled-down models of the steel frame under the far-field explosion load are similar. And the damage effects of the prototype and the scaled-down models based on the assessment index of interlayer displacement angle are similar.
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Key words:
- similarity law /
- steel frame /
- far-field explosion /
- dynamic response
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表 1 爆炸毁伤问题中变量的量纲幂次指数
Table 1. Dimensional power coefficients of variables in explosion damage problems
物理量 M L T $l,{l_1},{l_2},{l_3},{H_{\text{c}}},h$ 0 1 0 ${M_{\text{b}}},{M_{\text{c}}}$ 1 2 -2 ${N_{\text{b}}},{N_{\text{c}}}$ 1 1 -2 ρ 1 -3 0 E 1 1 -2 ν 0 0 0 σy 1 -1 -2 p 1 -1 -2 t 0 0 1 表 2 爆炸毁伤问题中自变量相似准数
Table 2. Similar parameters of independent variables in explosion damage problems
$ {\varPi _1} $ $ {\varPi _2} $ $ {\varPi _3} $ $ {\varPi _4} $ $ {\varPi _5} $ $ {\varPi _6} $ $ {\varPi _7} $ $ {\varPi _8} $ $ {\varPi _9} $ $ \dfrac{{{l_1}}}{l} $ $ \dfrac{{{l_2}}}{l} $ $ \dfrac{{{l_3}}}{l} $ $\dfrac{{{H_{\text{c}}}}}{l}$ $ \dfrac{h}{l} $ $\dfrac{{{M_{\text{b}}}}}{{{\sigma _{\text{y}}}{l^3}}}$ $\dfrac{{{N_{\text{b}}}}}{{{\sigma _{\text{y}}}{l^2}}}$ $\dfrac{{{M_{\text{c}}}}}{{{\sigma _{\text{y}}}{l^3}}}$ $\dfrac{{{N_{\text{c}}}}}{{{\sigma _{\text{y}}}{l^2}}}$ 表 3 炸药的材料参数
Table 3. Material parameters of explosive
ρt / (kg∙m−3) A / GPa B / GPa R1 R2 $ \omega $ DCJ / (m∙s−1) PCJ / GPa E0 / (kJ∙m−3) 1630 373.77 3.7471 4.15 0.9 0.35 6930 21 6×106 表 4 钢材J-C模型参数
Table 4. The J-C model parameters of steel
ρ / (kg∙m−3) E / GPa ν B / MPa C n m $ {\dot \varepsilon _0}/{{\text{s}}^{ - 1}} $ 7850 210 0.3 280 0.022 0.4 1.03 1 表 5 钢框架材料属性
Table 5. Material properties of steel frame
子结构试件 $ {f_{\text{y}}} $/ MPa $ {f_{\text{u}}} $/ MPa 梁翼缘 345 464 梁腹板 353 463 柱翼缘 420 529 柱腹板 407 539 端板 305 417 表 6 钢框架不同工况下应变率计算
Table 6. Strain rate of the steel frame under different conditions
工况1 比例1/5 应变率计算值/s−1 工况2 比例1/5 应变率计算值/s−1 30 kg,5 m m 0.5590 30 kg,6 m m 0.3475 3750 kg,25 m p 0.1038 3750 kg,30 m p 0.0711 表 7 钢框架缩比模型相似比
Table 7. The similarity ratios of the scaled steel-frame models
模型 原型 比例1/2 比例1/5 比例1/10 比例1/20 相似比 1 1/2 1/5 1/10 1/20 表 8 与结构损伤状况相对应的层间位移角限制
Table 8. Interlayer displacement angle limit corresponding to structural damage
性能水平 损伤状态 层间位移角 / % Ⅰ 完好 δ ≤ 0.2 Ⅱ 很轻微破坏 0.2 < δ ≤ 0.5 Ⅲ 轻微破坏 0.5 < δ ≤ 0.7 Ⅳ 中等破坏 0.7 < δ ≤ 1.5 Ⅴ 严重破坏 1.5 < δ ≤ 2.5 Ⅵ 很严重破坏 2.5 < δ ≤ 5.0 Ⅶ 倒塌 δ > 5.0 -
[1] AL-THAIRY H. A modified single degree of freedom method for the analysis of building steel columns subjected to explosion induced blast load [J]. International Journal of Impact Engineering, 2016, 94: 120–133. DOI: 10.1016/j.ijimpeng.2016.04.007. [2] 李忠献, 刘志侠, 丁阳. 爆炸荷载作用下钢结构的动力响应与破坏模式 [J]. 建筑结构学报, 2008, 29(4): 106–111. DOI: 10.14006/j.jzjgxb.2008.04.018.LI Z X, LIU Z X, DING Y. Dynamic responses and failure modes of steel structures under blast loading [J]. Journal of Building Structures, 2008, 29(4): 106–111. DOI: 10.14006/j.jzjgxb.2008.04.018. [3] 丁阳, 汪明, 李忠献. 爆炸荷载作用下钢框架结构连续倒塌分析 [J]. 建筑结构学报, 2012, 33(2): 78–84. DOI: 10.14006/j.jzjgxb.2012.02.011.DING Y, WANG M, LI Z X. Numerical analysis on damage and collapse process of steel frame structures under blast loads [J]. Journal of Building Structures, 2012, 33(2): 78–84. DOI: 10.14006/j.jzjgxb.2012.02.011. [4] 陈晔. 爆炸与次生火灾联合作用下钢结构损伤破坏及连续倒塌研究 [D]. 天津: 天津大学, 2016: 100–130.CHEN Y. Damage evaluation and progressive collapse research of steel structures subjected to explosion and post-explosion fire [D]. Tianjin, China: Tianjin University, 2016: 100–130. [5] 张秀华, 张宇, 段忠东, 等. 爆炸荷载作用下钢柱的动力响应与影响因素分析 [J]. 防灾减灾工程学报, 2014, 34(1): 73–77, 84. DOI: 10.13409/j.cnki.jdpme.2014.01.011.ZHANG X H, ZHANG Y, DUAN Z D, et al. Dynamic response and influence factor analysis of steel columns under blast loading [J]. Journal of Disaster Prevention and Mitigation Engineering, 2014, 34(1): 73–77, 84. DOI: 10.13409/j.cnki.jdpme.2014.01.011. [6] 张秀华, 吕晨旭, 李玉顺. 爆炸荷载作用下焊接工字钢梁的动力响应及破坏模式分析 [J]. 沈阳建筑大学学报(自然科学版), 2014, 30(3): 408–413. DOI: 10.11717/j.issn:2095-1922.2014.03.04.ZHANG X H, LÜ C X, LI Y S. Analysis of dynamic responses and failure modes of welded I-shaped steel beams subject to blast loadings [J]. Journal of Shenyang Jianzhu University (Natural Science), 2014, 30(3): 408–413. DOI: 10.11717/j.issn:2095-1922.2014.03.04. [7] JAMA H H, BAMBACH M R, NURICK G N, et al. Numerical modelling of square tubular steel beams subjected to transverse blast loads [J]. Thin-Walled Structures, 2009, 47(12): 1523–1534. DOI: 10.1016/j.tws.2009.06.004. [8] NASSR A A, RAZAQPUR A G, TAIT M J, et al. Experimental performance of steel beams under blast loading [J]. Journal of Performance of Constructed Facilities, 2012, 26(5): 600–619. DOI: 10.1061/(ASCE)CF.1943-5509.0000289. [9] 钟渝楷, 姜正荣, 姚小虎, 等. 考虑几何偏差及重力影响的单层网壳冲击相似律研究 [J]. 振动与冲击, 2018, 37(3): 230–236. DOI: 10.13465/j.cnki.jvs.2018.03.036.ZHONG Y K, JIANG Z R, YAO X H, et al. Impact comparability rule for single layer reticulated shells considering effects of geometric deviation and gravity [J]. Journal of Vibration and Shock, 2018, 37(3): 230–236. DOI: 10.13465/j.cnki.jvs.2018.03.036. [10] FU S Q, GAO X N, CHEN X. The similarity law and its verification of cylindrical lattice shell model under internal explosion [J]. International Journal of Impact Engineering, 2018, 122: 38–49. DOI: 10.1016/j.ijimpeng.2018.08.010. [11] 谈庆明. 量纲分析 [M]. 合肥: 中国科学技术大学出版社, 2005: 9–18.TAN Q M. Dimensional analysis [M]. Hefei: China University of Science and Technology Press, 2005: 9–18. [12] KINNEY G F, GRAHAM K J. Explosive shocks in air [M]. Berlin, Germany: Springer, 1985: 94–106. DOI: 10.1007/978-3-642-86682-1. [13] DINU F, MARGINEAN I, DUBINA D, et al. Experimental testing and numerical modeling of steel frames under close-in detonations [J]. Procedia Engineering, 2017, 210: 377–385. DOI: 10.1016/j.proeng.2017.11.091. [14] JOHNSON G R, COOK W H. A constitutive model and data for metals subjected to large strains, high strain rates and high temperatures [J]. Engineering Fracture Mechanics, 1983, 21: 541–548. [15] JOHNSON G R, COOK W H. Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures [J]. Engineering Fracture Mechanics, 1985, 21(1): 31–48. DOI: 10.1016/0013-7944(85)90052-9. [16] Department of the Army. Fundamentals of protective design for conventional weapons: TM-5-855-1 [S]. Washington, USA: Department of the Army, 1986. [17] 崔子鑫, 李海超, 庞彧, 等. Conwep算法和压力时程曲线荷载施加法在爆炸毁伤分析中的适用性 [J]. 军事交通学院学报, 2021, 23(1): 88–94. DOI: 10.16807/j.cnki.12-1372/e.2021.01.018.CUI Z X, LI H C, PANG Y, et al. Applicability of Conwep algorithm and pressure-time curve load application method in explosion damage analysis [J]. Journal of Military Transportation University, 2021, 23(1): 88–94. DOI: 10.16807/j.cnki.12-1372/e.2021.01.018. [18] 甘露, 陈力, 宗周红, 等. 近距离爆炸比例爆距的界定标准及荷载模型 [J]. 爆炸与冲击, 2021, 41(6): 064902. DOI: 10.11883/bzycj-2020-0194.GAN L, CHEN L, ZONG Z H, et al. Definition of scaled distance of close-in explosion and blast load calculation model [J]. Explosion and Shock Waves, 2021, 41(6): 064902. DOI: 10.11883/bzycj-2020-0194. [19] 陈绍蕃, 顾强. 钢结构基础 [M]. 2版. 北京: 中国建筑工业出版社, 2007: 318–330. [20] DUSENBERRY D O. Handbook for blast-resistant design of buildings [M]. Hoboken, NJ, USA: Wiley, 2010: 119–129. [21] 林莉, 黄博, 肖新科, 等. Q355B钢动态材料性能研究 [J]. 振动与冲击, 2020, 39(18): 231–237. DOI: 10.13465/j.cnki.jvs.2020.18.031.LIN L, HUANG B, XIAO X K, et al. Behavior of dynamic material Q355B steel based on the Johnson-Cook model [J]. Journal of Vibration and Shock, 2020, 39(18): 231–237. DOI: 10.13465/j.cnki.jvs.2020.18.031. [22] Department of Defense. DoD minimum antiterrorism standards for buildings: UFC 4-010-01 [S]. Washington, USA: Department of Defense, 2012: 24–25. [23] Department of Defense. Component explosive damage assessment workbook (CEDAW): USACE ECB 2005-13 [S]. Washington, USA: Department of Defense, 2005: 26–37. [24] Pourbehi M S. Design of blast-resistant buildings in petrochemical facilities [M]. The United States: Malek Ashtat Press, 1999: 5–22. [25] 同济大学, 天津大学. 民用建筑防爆设计标准: T/CECS 736—2020 [S]. 北京: 中国建筑工业出版社, 2020.Tongji University, Tianjin University. Standard for blast protection design of civil buildings: T/CECS 736—2020 [S]. Beijing: China Architecture & Building Press, 2020. [26] 肖绍添. 爆炸荷载作用下钢管混凝土框架结构损伤与倒塌数值分析 [D]. 广州: 广州大学, 2019: 64.XIAO S T. Numerical analysis of damage and collapse of concrete-filled steel tube frame structure under blast load [D]. Guangzhou: Guangzhou University, 2019: 64. [27] 中华人民共和国住房和城乡建设部, 中华人民共和国国家质量监督检验检疫总局. 建筑抗震设计规范: GB 50011—2010 [S]. 北京: 中国建筑工业出版社, 2010.Ministry of Housing and Urban-Rural Development of the People s Republic of China, General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China. Code for seismic design of buildings: GB 50011—2010 [S]. Beijing: China Architecture & Building Press, 2010. [28] COUNCIL A T, ROJAHN C, SHAPIRO D, et al. NEHRP guidelines for the seismic rehabilitation of buildings[Z]. Washington: Federal Emergency Management Agency, 1997: 2–12. [29] WEN Y K, KANG Y J. Minimum building life-cycle cost design criteria: applications [J]. Journal of Structural Engineering, 2001, 127(3): 338–346. DOI: 10.1061/(asce)0733-9445(2001)127:3(338).