摘要
本文以应县木塔结构加固维修工程为背景,采用地基微波干涉雷达对应县木塔进行动态结构检测,应用希尔伯特—黄变换(Hilbert-Huang Transform,HHT)进行结构模态参数识别。为提高参数识别精度采用经验模态分解(Empirical Mode Decomposition,EMD)对高频检测数据进行降噪重构,准确计算出木塔的一至五层的固有频率,并分析出木塔在检测期间的缓慢变形规律,为分析木塔的结构特性与木塔的结构修复、安全保护提供可靠的数据支撑。
In this paper,the dynamic structure deformation of the wooden tower is detected by groundbased microwave interference radar in the project of reinforcement and repair of the Yingxian wooden tower.The Hilbert-Huang Transform( HHT) is used to identify the modal parameters of the monitoring data. In order to improve the accuracy of parameter,Empirical Mode Decomposition( EMD) is used to de-noise and reconstruct the high-frequency to accurately calculate the natural frequencies of the wooden tower from one to five layers. The obtained slow deformation can be used to analyze the structural characteristics and provide reliable data support for the structure repair and safety protection of the wooden tower.
引文
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