设计，建议考虑规范冲击系数和车辆一般运行状态进行疲劳验算;对既有桥梁疲劳评估，建议按实际交通状况考虑随机车辆冲击效应、车流运行状态和桥面退化的影响.
关键词：疲劳损伤评估;混凝土桥梁;横向联系;车桥耦合振动;桥面退化
中图分类号：U441.3 文献标志码：A
文章编号：1674—2974（2019）09—0079—10
Abstract：To study the effect of actual operational condition on the fatigue damage of lateral connection structure for fabricated concrete girder bridges， a fatigue damage assessment framework for the steel plate connection structure of this bridge type was presented based on linear Miner cumulative damage criterion. The influence rules of dynamic impact effects from stochastic traffic， traffic condition and progressive deterioration of bridge deck roughness on the fatigue damage of lateral connections were studied through an actual bridge example. The results show that the fatigue life of the transversal beam is obviously underestimated when considering the vehicular impact effect under Chinese specification compared with that of stochastic traffic with 95% confidence level. Traffic condition also has a significant influence on the fatigue damage， and the structural fatigue cumulative damage under intensive traffic condition is smaller than that of general one. Progressive deterioration of bridge deck condition has an obvious effect on the fatigue damage. The fatigue life of lateral connection decreased by 60.01% and 34.88% under general and intensive traffic conditions considering bridge deck degradation. When designing a new bridge， the impact factors from specification and general traffic condition should be considered in the fatigue calculation for lateral connection structure. It is suggested that considering the influence of stochastic traffic dynamic impact，operation traffic status and progressive deterioration of bridge deck was necessary when evaluating lateral connection fatigue damage for the existing bridges.
Key words：fatigue damage evaluation;concrete bridges;lateral connection;vehicle-bridge coupled vibration;progressive deterioration of bridge deck
裝配式混凝土肋梁桥通过翼缘板和横隔梁的横向连接使各主梁共同承担车辆荷载作用.有桥梁调查表明[1-2]重载交通的长期反复作用造成的疲劳累积损伤是导致该类桥梁横向联系构件破损和断裂的重要原因，其中又以钢板连接的横向联系损伤问题最为突出[3].横向联系损伤将影响上部结构整体受力性能，严重时可导致“单梁受力”等局部超载现象发生.我国现行桥梁设计规范对此类构件未给出明确的疲劳损伤评估方法及具体防护措施.