研究直接利用健康监测系统实测应力对钢箱梁进行疲劳评估。采用雨流计数法技术统计分析应力时程数据得到日应力谱,由多天的日应力谱进行统计平均得到标准日应力谱。基于线性累积损伤准则和钢箱梁各连接部位的疲劳强度曲线,对其进行疲劳损伤评估,并根据交通状况的改变实时更新评估结果。结合某大桥健康监测系统,采用提出的方法对其钢箱梁进行疲劳评估。结果表明,U肋与横隔板连接部位将产生疲劳损伤,需加强维护。 The fatigue assessment of steel box girders is conducted by directly using the measured stress of the health monitoring system. Rainfall flow counting method was used to analyze the stress time history data to obtain the daily stress spectrum. The daily stress spectrum was obtained from the multi-day daily stress spectrum to obtain the standard daily stress spectrum. Based on the linear cumulative damage criterion and the fatigue strength curves of the steel box girders, the fatigue damage was evaluated and the results of the assessment were updated in real time according to the changes of traffic conditions. Combined with a bridge health monitoring system, the proposed method is used to evaluate the fatigue of the steel box girder. The results show that the connection between the U-rib and the diaphragm will cause fatigue damage, which requires more maintenance.