摘要
斜拉索是现代斜拉桥最重要的结构构件,索力在斜拉桥的施工控制和长期监测中起着重要作用。振动测试法是斜拉桥索力测定、监测和状态评估中应用最广泛的一种方法。振动法测索力的关键在于准确地识别出索的基频。本文使用自功率谱和倒频谱方法,基于MATLAB平台,开发出了斜拉桥拉索环境振动模态分析图形用户交互(GUI)工具箱,实现了斜拉索基频的快速自动识别。应用本文的方法,对福州青洲闽江主跨605m斜拉桥拉索的环境振动实测加速度数据进行了分析处理,斜拉索基频识别方便直观,结果可靠。
Stay cables are the most critical structural components in modern cable-stayed bridges. The cable tension plays an essential role in the construction control and long-term monitoring of cable-stayed bridges. Experimental vibration measurement is one of the most widely used methods for tension evaluation and condition assessment of cable-stayed bridges. There is a unique relationship betweenthe tension force and fundamental frequency of the stay cable. The key to success of this technique is the accuracy of identified fundamental frequency of each stay cable. In this paper, experimental modal analysis of bridge stay cables is carried out using output-only acceleration records of the stay cables. An automated data analysis to determine cable fundamental frequencies is proposed with the power spectral density (PSD) and cepstrum method. Application of the automated analysis approach to the cables of the bridge at Qingzhou across Minjiang river, from ambient vibration measurements demonstrated high identification accuracy and confidence.
出处
《地震工程与工程振动》
CSCD
北大核心
2003年第3期100-106,共7页
Earthquake Engineering and Engineering Dynamics
基金
福建省自然科学基金(F0210007)
福建省科技计划重点项目(2002H027)
