大跨钢桁拱轨道横梁半刚性连接的疲劳荷载

Fatigue Load for Semi-rigid Connection of Rail Floor Beam of Long-Span Steel Truss Arch Bridges

为评定公路与轻轨两用钢桁拱桥轨道横梁与主桁半刚性连接在车辆荷载作用下的疲劳损伤累积,对该构造细节在桥梁设计寿命期内车辆荷载产生的疲劳荷载谱的计算方法进行了研究.针对我国公路桥梁设计规范暂无疲劳荷载规定的情况,参照美国AASHTO规范,建立了反映桥梁设计寿命期内真实运营状况的疲劳荷载模型,并通过全桥三维有限元分析计算了该构造细节的荷载历程.根据疲劳损伤累积理论,确定了钢桁拱轨道横梁与主桁半刚性连接的疲劳试验荷载.

In order to estimate the fatigue damage accumulation of semi-rigid connection between the rail floor beam and truss of a steel truss arch bridge bearing light rail transit and highway vehicle loads, fatigue load spectrum, produced due to traffic loads in the designed service life of the bridge, for the semi-rigid connection was investigated. Based on the analysis of traffic loads and the AASHTO specification, a fatigue load model to reflect the actual running state of the bridge during the designed service life was established. A 3-D finite element analysis was made to simulate the load history for the semi-rigid connection. Based on the fatigue damage accumulation theory,fatigue test load for the semirigid connection was determined.