數位攝影量測技術應用於斜張鋼纜振態頻率識別之研究

Application of Digital Photometry Techniques in Identifying the Modal Frequencies of Stay Cables

陳建州(Chien-Chou Chen) ； 吳文華(Wen-Hwa Wu) ； 曾宏正(Hong-Zeng Tseng) ； 賴國龍(Gwo-Long Lai) ； 謝昱德(I-Der Shieh)

《中國土木水利工程學刊》 22卷4期 (2010/12) Pp. 411-421

https://doi.org/10.6652/JoCICHE.201012_22(4).0006

摘要

隨著製造技術的快速進步，數位攝影機除了解析度與取樣頻率大幅度提升外，其價格亦逐年降低，且操作方式更加簡易，因此數位攝影量測技術近來開始被嘗試應用於各種物理量的量測與識別。本文之目標即在開發一般商品化彩色攝影機於結構物微振量測之應用，並進而探討據其識別相關振態頻率的各項問題與處理方法。此研究所建構的影像量測技術已成功應用於南投集鹿斜張橋鋼纜的現地微振量測，其振態頻率識別結果證明可達到與使用精密速度計幾乎同等級的精度。

關鍵字

數位攝影 ； 振態頻率 ； 微振訊號 ； 斜張鋼纜

並列摘要

Benefiting from the rapid advances in related technologies, digital camcorders have not only been significantly improved in image resolution and sampling frequency, but also become much more popular because of friendly operation and reduced cost. Consequently, the technique of digital photometry has recently been attempted for its possible application in the measurement and identification of various physical quantities. This paper is aimed to develop the application of consumer grade digital camcorders in the ambient vibration measurements of structures. Furthermore, several problems and corresponding solutions in identifying the modal frequencies based on these measurements are also explored. The proposed digital photometry technique has been successfully applied in the on-site ambient vibration measurements for the stay cables of Chi-Lu Bridge and the subsequent identified results of modal frequencies clearly verify that it hold almost the same order of accuracy as that with high-resolution velocimeters.

並列關鍵字

digital photometry ； modal frequency ； ambient vibration signal ； stay cable