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为研究树脂沥青组合体系(ERS)铺装对钢桥面板疲劳应力的影响,开展钢箱梁桥面板现场试验研究。采用总重200 k N的两轴卡车加载,铺装前后分别进行了390个静力工况测试,获取了铺装前后的钢桥面板典型细节应力响应面与响应线。基于现场测试数据建立钢桥面板有限元模型,研究了气温和铺装厚度变化对典型细节疲劳应力的影响。运营期间对钢桥面板进行长期动应变监测,分别选取不同季节连续24 h内实测应力谱进行应力幅分析与疲劳损伤评估。结果表明:ERS铺装使得钢桥面板疲劳应力水平降低7.1%~46.5%,对纵肋与顶板连接细节影响最大;气温和铺装厚度的变化对不同细节疲劳应力的影响差异显著;相同车流作用下冬季实测峰值应力幅约为夏季的50%,秋季峰值应力幅约为夏季的70%;夏季产生的疲劳损伤是秋季的2.5倍,是冬季的15倍以上,建议钢桥面板疲劳验算或评估时充分考虑桥面铺装温度和厚度的影响。
In order to study the influence of resin asphalt composite system (ERS) on the fatigue stress of steel bridge deck, a field test of steel box girder bridge deck was carried out. The two-axle truck loaded with a total weight of 200 kN was loaded with 390 static condition tests before and after pavement. Typical stress response surface and response line of steel bridge deck before and after pavement were obtained. Based on the field test data, the finite element model of the steel bridge deck was established and the influence of the variation of temperature and pavement thickness on the fatigue fatigue of typical details was studied. Long-term dynamic strain monitoring of steel bridge deck during operation was carried out. Stress amplitude analysis and fatigue damage assessment were carried out by using measured stress spectra in different seasons for 24 consecutive days respectively. The results show that ERS pavement reduces the fatigue stress of steel deck by 7.1% -46.5%, and affects the connection details of longitudinal rib and roof most significantly. The influence of temperature and pavement thickness on the fatigue stress of different details is significant. The peak measured stress in winter is about 50% in summer and the peak in autumn is about 70% in summer. The fatigue damage in summer is 2.5 times of that of autumn and 15 times of that in winter. It is suggested that the fatigue test or assessment Full account of deck pavement temperature and thickness effects.