刚性悬索加劲连续钢桁梁受力特性成桥试验研究

石济客运专线济南黄河公铁两用桥主桥采用了三桁式刚性悬索加劲连续钢桁梁的特殊结构形式,针对此桥梁的结构特点,开展了成桥专项试验研究。首先测试了外荷载作用下桥梁3片主桁挠度及相应杆件应力的横向分配。其次,测试了有砟轨道铁路桥梁正交异性桥面体系在列车局部轮载作用下各构造细节的受力特征。最后,对刚性悬索加劲钢桁梁上弦杆与加劲弦连接处特殊节点的受力特性进行了测试。实测结果表明:桥梁3片主桁横向具有较好的整体性;有砟轨道铁路桥梁的正交异性桥面体系各构造细节均未出现明显的应力集中效应;特殊节点板受力特征与有限元计算结果吻合,连接板圆弧倒角处应力较大。

Completed Bridge Test Study on Mechanical Performance of Continuous Steel Truss Girder Reinforced by Stiff Suspension Cables

The Jinan Yellow River Rail-cum-road Bridge in Shijiazhuang-Jinan Passenger Dedicated Railway adopts a special structure of three-truss continuous steel truss girder reinforced by stiff suspension cables.A special test study was conducted according to the structural characteristics of the bridge.Firstly,the deflections of the three trusses and the stress distribution of the corresponding members under the external loads were tested.Secondly,the stress characteristics of the orthotropic steel deck system with ballasted track were tested under the local wheel load of the train.Finally,the stresses of the special joints between the upper chords of the rigid suspension cable and the stiffened chords were tested.The test results show that the three main trusses of the bridge have good integrity in the transverse direction.There is no obvious stress concentration effect in each configuration details of the orthotropic steel deck system with ballasted track.The mechanical performance of the special joints are in accordance with the calculated results from finite element analysis,and the stress at the arc chamfering position of the connecting plate is larger.