采用环境脉动法对CFRP拉索斜拉试验桥进行模态试验。联合采用峰值拾取法和互功率谱(PSD)法来识别模态参数,并将其与有限元模型计算结果进行对比分析;按等轴向刚度准则将CFRP索替换为钢索,比较不同索模型的动力特性。结果表明:实测结果与计算结果基本吻合,相对钢索,CFRP索斜拉桥自振频率有所提高。
The modal test for an experimental cable-stayed bridge used with CFRP stay cables was made by the environmental pulsating method and the modal parameters of the bridge were identified by the joint peak picking method and cross-power spectral density (PSD) method and were then comparatively analyzed in accordance with the results calculated by the finite element model. Meanwhile, the CFRP cables were also substituted for steel cables in conformity to the equivalent axial stiffness principle and the dynamic behavior of the models of the two kinds of the cables were compared. The results reveal that the testing values agree with the calculation ones on the whole and in comparison to the cable-stayed bridge used with steel cables, the natural vibration frequency of the bridge used with CFRP cables increases a little.