Abstract：This paper investigates the measured variability in modal frequencies of a suspension bridge induced by temperature, wind, traffic loadings and identification algorithm simultaneously making use of long-term monitoring data. First the seasonal temperature-frequency correlation is formulated using multi-sample averaging technique to reduce the random variations rising from the identification algorithm. Then the effect of temperature on the measured modal frequencies is eliminated by normalizing these modal frequencies to a reference temperature. The traffic-induced modal variability is further quantitatively evaluated under weak wind conditions by correlation the normalized modal frequencies with the root mean square (RMS) of acceleration responses. Based on the traffic-frequency correlation models, the effect of traffic loadings on the modal frequencies is eliminated and the wind-induced modal variability is quantitatively evaluated. The results indicates that the technique proposed in this study can effectively give a quantitative evaluation of measured variability in modal frequencies of long-span bridges and however at present it still needs to improve the identification algorithm of the modal frequency.
邓扬;丁幼亮;李爱群. 环境条件影响下悬索桥模态频率变异性的定量评价[J]. , 2011, 30(8): 230-236.
Deng Yang;Ding You-liang;Li Ai-qun. Quantitative evaluation of variability in modal frequencies of a suspension bridge under environmental conditions. , 2011, 30(8): 230-236.
2011, Vol. 30 
