基于环境振动测试的桥梁动力特性

Dynamic Characteristics for Cables-stayed Bridge Based on Ambient Vibration Testing

在环境激励下对武汉理工大学理工一桥进行了动力测试,在此基础上分析了该桥梁的动力特性。重点测试了斜拉桥的索力和桥梁的振动特性,采用频差法和新基频法识别斜拉索的基频,由此求出了索力;由导纳圆拟合法识别出了桥梁的模态参数。通过实测结果与理论计算结果的比较研究,分析了桥梁的动力特性,掌握了其实际工作状态和运营情况,为进一步研究桥梁的健康检测提供了科学依据。

The dynamic characteristics of Ligong First Bridge of Wuhan University of Technology were analyzed based on its dynamic testing results under ambient excitation. This article emphasized on the testing of the cable tensions of cable-stayed bridges and its vibration characteristics. The former identified the cable＇ s eigenfrequency by frequency difference method and new eigenfrequency method respectively, and thus the cable tension values were obtained. The latter identified the modal parameters of the bridge by admittance circle fitting method. Compared with the theoretical ones, the dynamic characteristics of the bridge were analyzed. Therefore, its real operating conditions were understood, which provided scientific references for future research on bridge health monitoring system.