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论文类型：会议论文

发表时间：2015-01-01

收录刊物：Scopus

摘要：As important structural components of a long-span cable stayed bridge, accurate condition assessment of stay cables have received significant public attention in recent years. To do so, a dynamic-based model-free damage diagnosis method of stay cables using the changes in natural frequencies is presented in this paper. The most useful damage diagnosis methods are probably those using frequency changes because frequency measurements can be quickly conducted and are often reliable. In recognizing the fact that damage in a stay cable will cause the change of its natural frequency, the proposed method uses the frequency difference of a stay cable to diagnosis the cable. However, the frequency change is possibly submerged by the surrounding noise and error in the process of parameter identification, especially when the damage is small. To address the limitation, the proposed method employs a temporary diagonal steel bar, which is installed with one end on the stay cable close to the bottom anchor head and the other end on the bridge deck; as a result, the stay cable is divided into two parts, i.e. a short part and a long part. Because the natural frequency of a stay cable will increase with the decrease of its length, the frequency change will be amplified for the same damage. Numerical simulation of a stay cable selected from a cable-stayed bridge is used to validate the method in this work, and the results under ambient excitation show that the proposed method can be well used in the damage diagnosis of stay cables. ? 2015, International Society for Structural Health Monitoring of Intelligent Infrastructure, ISHMII. All rights reserved.