新水东大桥引桥的成桥荷载研究

Field load of the newly-built Shuidong approach bridge

为准确评定新建桥梁的承载能力和评价其实际技术状况,对新水东大桥引桥这一预应力混凝土连续梁桥开展成桥荷载试验研究。利用有限元分析软件Midas/Civil计算试验加载工况的荷载效应理论值;用等效车辆荷载实施静力加载,并通过环境随机激励完成模态试验,测试计算出静载工况下各控制截面的挠度、应力及结构的基频。试验中采取有效措施确保挠度测试的准确性。成桥荷载试验结果表明,新水东大桥引桥承载能力和刚度满足设计要求,可以保证桥梁投入使用后的运营安全。

A load test was carried out on the newly-built Shuidong approach bridge to evaluate the bearing capacity and assess the technical condition, which is a pre-stressed concrete continuous beam bridge. A finite dement model was developed by using Mi- das/Civil software to compute the theoretical values of the bridge＇s structural response to the designated loading cases. Static loading was simulated by equivalent vehicle loads, and modal test by means of environmental random excitation were accomplished to measure the deflections and stresses of each control cross-sections, and the fundamental frequency of the approach bridge. Effi- cient measurement was adopted to ensure the accuracy of deflection testing. The testing results showed that the load-bearing ca- pacity and stiffness of this approach bridge met the design requirements, and the service safety of the Shuidong approach bridge can be ensured in service.