拱桥吊杆锈蚀高强钢丝疲劳性能试验研究

发布时间：2018-11-28 13:11

【摘要】：为了评价拱桥服役吊杆的残余寿命,以使用10余年的吊杆高强钢丝为对象,通过自然锈蚀、人工锈蚀及机械损伤方法得到轻微锈蚀、严重锈蚀以及点蚀状态的钢丝样本,根据拉伸试验和疲劳试验、破坏断口形貌分析,研究了锈蚀钢丝的拉伸性能、疲劳寿命以及破断机理。在此基础上用精细有限元计算模型分析蚀坑对钢丝应力集中的影响。试验结果表明,锈蚀对钢丝的拉伸强度影响不大,承载力变化主要取决于钢丝有效截面的减少程度;锈蚀导致钢丝的延性下降;钢丝疲劳性能受锈蚀程度的影响具有先敏感后迟钝的特征,即锈蚀初期钢丝的疲劳寿命因锈蚀而显著降低,但进一步锈蚀引起的钢丝疲劳寿命下降不明显。有限元分析结果表明,点蚀钢丝的疲劳寿命不仅取决于蚀坑底部的应力集中程度,还受到应力集中区域的影响。
[Abstract]:In order to evaluate the residual life of suspenders in service of arch bridges, specimens of mild, severe and pitting steel wires were obtained by natural corrosion, artificial corrosion and mechanical damage methods, which were used for more than 10 years. Based on tensile test and fatigue test, the tensile properties, fatigue life and fracture mechanism of corroded steel wire were studied. On this basis, the fine finite element model is used to analyze the effect of the corrosion pit on the stress concentration of steel wire. The results show that corrosion has little effect on the tensile strength of steel wire, and the change of bearing capacity mainly depends on the reduction of effective section of steel wire, the ductility of steel wire decreases due to corrosion. The fatigue property of steel wire can be affected by the degree of corrosion. The fatigue life of steel wire at the beginning of corrosion is obviously reduced by corrosion, but the fatigue life of steel wire caused by further corrosion is not obvious. The results of finite element analysis show that the fatigue life of pitting steel wire depends not only on the stress concentration at the bottom of the pit, but also on the stress concentration area.
【作者单位】：浙江大学;金华市公路管理局;浙江省公路管理局;
【基金】：浙江省交通科技资助(2012H47) 国家自然科学基金(51378460)
【分类号】：U441.4

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