公铁两用铆接钢桁梁桥拓宽改建荷载试验分析

Load Test Analysis of Riveted Steel Truss Rail-cum-Road Bridge after Widening and Reconstruction

上海市松浦大桥原为跨越黄浦江的双层公铁两用桥,主桥为2联(96+112)m连续铆接三角形钢桁梁结构,根据交通需要将其在原位拓宽改建。为了测试桥梁的实际受力状况,检验改建的设计、施工质量,验证结构安全性与改造的有效性,对原位改建完成后的桥梁进行了荷载试验,包括静载试验、动载试验及自振特性参数测试,获取了原位拓宽改建后桥梁结构关键杆件的应力、变形、自振频率等结构参数。试验结果表明:1)桥梁结构受力与理论计算基本一致;2)承载力满足设计要求;3)采用的的改造方法合理有效。

Songpu Bridge was originally a double-layer rail-cum-road bridge crossing the Huangpu River in Shanghai.The main bridge is a double(96+112)m continuous riveted triangular steel truss beam.It is widened and reconstructed in situ according to traffic needs.In order to test the actual stress condition of the bridge,inspect the design and reconstruction quality,and verify the structural safety and effectiveness of the reconstruction,load tests were carried out on the bridge after the completion of the in-situ reconstruction,including static load test,dynamic load test and natural vibration characteristic parameter test.The stress,deformation,natural frequency and other structural parameters of key members of the bridge structure after in-situ widening and reconstruction are obtained.The test results show that the stress of the bridge structure is basically consistent with the theoretical calculation,the bearing capacity meets the design requirements,and the transformation method adopted is reasonable and effective.