ERS铺装对钢桥面板疲劳性能的影响及参数分析

为了研究树脂沥青组合铺装体系(ERS)对正交异性钢桥面板疲劳性能的影响,以宜昌伍家岗长江大桥为工程背景,采用ANSYS软件分别建立有、无铺装层的钢桥面板足尺节段有限元模型,针对不同温度条件下铺装层对钢桥面板疲劳性能的影响作用进行系统研究。结果表明:考虑铺装层与钢桥面板的协同受力之后,U肋与顶板焊接细节4个疲劳易损部位的应力幅值均显著降低;ERS铺装层温度对U肋与顶板焊接细节的疲劳性能具有显著影响,其中对顶板内侧和外侧焊趾的影响最为显著,相对于不考虑铺装层的情况,在铺装层温度为55℃时顶板内侧和外侧焊趾的等效应力幅值分别降低49.8%和46.9%,而在铺装层温度为5℃时其等效应力幅值分别降低81.3%和88.1%;增加RA10层和SMA-13层的设计厚度均可降低U肋与顶板焊接细节的等效应力幅值,RA10层厚度参数对于钢桥面板疲劳性能的影响更加显著;为准确评估钢桥面板的疲劳性能,建议考虑ERS桥面铺装层温度以及厚度的影响。

Effects of ERS Pavement on Fatigue Performance of Steel Deck and Parametric Analysis

To study the effects of epoxy resin-asphalt composite system(ERS)on the fatigue performance of orthotropic steel deck,the Wujiagang Changjiang River Bridge is taken as a study case.The full-scale segmental models of steel deck with and without pavement were established by ANSYS to carry out systematic analysis of the effects of pavement on the fatigue performance of steel deck under different temperature conditions.The results indicate that when the synergic action of pavement and steel deck is considered,the stress amplitudes at four fatigue sensitive points in the welds between U ribs and top plates are significantly decreased.The fatigue performance of the welds between U ribs and top plates is sensitive to the temperature of ERS,especially on the welding toes on the inner and outer sides of top plates.Compared to the model without pavement,the equivalent stress amplitudes of welding toes on the inner and outer sides of top plates are decreased by 49.8% and 46.9%,respectively,when the temperature of pavement is at 55℃,and decreased by 81.3% and 88.1%,respectively,when the temperature of pavement is at 5℃.Increasing the design thickness of RA 10 and SMA-13 layers can also reduce the equivalent stress amplitudes of welds between U ribs and top plates,but the effect of thickness of RA10 on the fatigue performance of steel deck is more significant.It is suggested that the temperature and thickness of ERS pavement be considered,so as to accurately evaluate the fatigue performance of steel deck.