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 epoxy resin asphalt system( ERS) pavement on fatigue stress of steel bridge deck,in-situ experimental study on the deck of steel box girder is carried out. Three hundred and ninety static loading cases are conducted on two-axle truck with gross weight of 200 k N before and after paving,the response surfaces and the response lines of typical detailed stress in steel bridge deck are acquired. Based on in-situ test data,the finite element model of steel bridge deck is built to study the influences of temperature and pavement thickness on typical detailed fatigue stress. The long-term dynamic strain monitoring is conducted on steel bridge deck during service stage,and 24-hour recorded stress spectra in different seasons are selected to ana-lyze the stress ranges and assess the fatigue damage. The result shows that( 1) the fatigue stresses of steel bridge deck decreased by 7. 1% to 46. 5% due to ERS pavement,which has most influence on rib-to-deck detail;( 2) the influences caused by temperature and pavement thickness vary significantly for different detailed fatigue stresses;( 3) under the same traffic flow,the measured peak stress range in winter is about 50% of that in summer,and the peak stress range in autumn is about 70% of that in summer;( 4) the fatigue damage caused in summer is as 2. 5 times as that in autumn and more than15 times of that in winter. It is suggested that the influences of pavement temperature and thickness should be fully considered in fatigue check or fatigue assessment for steel bridge deck.