Civil and Traffic Engineering |
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Tensile mechanical behavior of parallel wire cables with wire breaks |
ZHANG Tingting, XIE Xu, PAN Xiaoyu |
Department of Civil Engineering, Zhejiang University, Hangzhou 310058, China |
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Abstract In order to analyze the tensile mechanical behavior of the parallel wire cables with broken wires, an analytical model based on the theory of bundles of threads was presented considering the effect of interwire friction. By laboratory test for three segment samples in different lengths extracted from parallel wire cables, the friction characteristics between wires in different layers were gained as input variables in the analytical model. This paper studied the stress redistribution of wires in cable due to wire breaks, and discussed the recovery tensile force of the broken wire, and the ultimate strength of the cable when considering the interwire friction. Laboratory test results showed from the segment in length of 10cm, that the average friction rigidity of unit length is about 0.192 kN/mm2, and the average friction resistance is 0.022 kN/mm. The wrapping force of the PE casing was not transmitting in the radial direction of cable crosssection. The theoretical calculation results showed that the tensile force of broken wires grew linearly with the distance from the breaking point, and the recovery length is about 1.5 m to 2.0 m due to the interwire friction. The ultimate strength of cable increased slightly compared to those without considering the interwire friction, and on the crosssection of the breaking point, the other wires shared the tensile force of the broken ones evenly.
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Published: 14 January 2017
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考虑断丝影响的平行钢丝索拉伸力学特性
为了分析断丝对平行钢丝索拉伸力学特性的影响,提出考虑钢丝间摩擦影响的纤维束计算模型.通过对3种不同高度索段试件顶推试验获得钢丝间的摩擦力特性,应用提出的纤维束计算模型分析钢索拉伸时断丝引起的内力重分布规律,讨论钢丝间的摩擦作用对断裂钢丝的张力恢复以及钢索承载能力等特性的影响.顶推试验结果表明,高度10 cm的平行钢丝索段试件,钢丝间的单位长度摩擦刚度均值为0.192 kN/mm2,单位长度滑动摩擦力均值为0.022 kN/m; PE套管的握裹力不会沿索截面的径向传递;理论计算结果表明,考虑钢丝间摩擦影响时,断裂钢丝的张力离开断口约1.5~2.0 m后线性恢复到断丝前的大小;考虑钢丝间摩擦影响的钢索承载能力略大于忽略摩擦影响的值;在断丝截面,未断裂的钢丝较均匀地分摊断裂钢丝释放的张力.
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[1]WEIBULL W. A statistical representation of fatigue failures in solids [M]. Goteborg: Elanders Boktryckeri Aktiebolag, 1949:5-12.
[2]DANIELS H E. The statistical theory of the strength of bundles of threads [J]. Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1945, 183(995): 405-435.
[3]MATTEO J, DEODATIS G, BILLINGTON D P. Safety analysis of suspensionbridge cables: Williamsburg Bridge [J]. Journal of Structural Engineering, ASCE, 1994, 120(11): 3197-3211.
[4]HAIGHT R Q, BILLIONGTON D P, KHAZEM D. Cable safety factors for four suspension bridges [J]. Journal of Bridge Engineering, ASCE, 1997, 2(4):157-167.
[5]CREMONA C. Probabilistic approach for cable residual strength assessment [J]. Engineering Structures, 2003, 25(3): 377-384.
[6]朱劲松,肖汝诚. 大跨度斜拉桥拉索安全性分析方法研究[J]. 土木工程学报, 2006, 39(9): 74-79.
ZHU Jinsong, XIAO Rucheng. A study on the safety assessment method for stay cables of longspan cablestayed bridges [J]. China Civil Engineering Journal. 2006, 39(9): 74-79.
[7]徐俊. 拉索损伤演化机理与剩余使用寿命评估[D]. 上海:同济大学, 2006: 98-111.
XU Jun. Damage evolution mechanism and remained service lives evaluation of stayed cables [D]. Shanghai: Tongji University, 2006: 98-111.
[8]徐宏. 桥梁拉 (吊) 索损伤后力学分析及安全评价[D]. 西安: 长安大学, 2008: 90-119.
XU Hong. Mechanical analysis and safety evaluation of bridge damaged cable [D]. Xian: Xian University, 2008: 90-119.
[9]李元兵. 拱桥吊杆力学行为及损伤退化研究[D]. 上海: 同济大学, 2008.
LI Yuanbing. Research on mechanical behavior and damage deterioration of suspender for arch bridges [D]. Shanghai: Tongji University, 2008.
[10]兰成明,平行钢丝斜拉索全寿命安全评定方法研究[D]. 哈尔滨:哈尔滨工业大学, 2009: 102-129.
LAN Chengming. Study on lifecycle safety assessment methods for parallel wire stay cable [D]. Harbin: Harbin Institute of Technology, 2009: 102-129.
[11]高欣. 在役钢管混凝土拱桥吊杆损伤与系统可靠性分析方法[D]. 哈尔滨: 哈尔滨工业大学, 2011: 97-102.
GAO Xin. Analysis methods for suspender damage and system reliability of existing concrete filled steel tubular arch bridge. Harbin: Harbin Institute of Technology, 2011: 97102.
[12]彭崇梅, 张启伟, 李元兵. 桥梁半平行钢丝索的对称断丝损伤力学模型[J]. 同济大学学报: 自然科学版, 2013, 41(1): 20-26.
PENG Chongmei, ZHANG Qiwei,LI Yuanbin. Damage model of multilayered semiparalleled wire cables for bridges with symmetric wire breaks [J]. Journal of Tongji University:Natural Science, 2013, 41(1): 20-26.
[13]彭崇梅, 张启伟, 李元兵. 桥梁半平行钢丝索对称断丝的力学特性分析[J]. 同济大学学报:自然科学版, 2013, 41(4):496-502.
PENG Chongmei, ZHANG Qiwei, LI Yuanbin. Mechanical properties analysis of semi parallel wire cables for bridge with symmetric wire breaks [J]. Journal of Tongji University :Natural Science, 2013, 41(4): 496-502.
[14]潘骁宇,谢旭,李晓章,等. 锈蚀高强度钢丝的力学性能与评级方法[J].浙江大学学报:工学版, 2014, 48(11): 1917-1924.
PAN Xiaoyu, XIE Xu, LI Xiaozhang et al. Mechanical properties and grading method of corroded hightensile steel wires [J]. Journal of Zhejiang University :Engineering Science, 2014, 48(11): 1917192. |
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