TY - EJOU AU - Zhang, Deyi AU - Bao, Yuequan AU - Zhou, Feng AU - Li, Hui TI - Modal identification of structure under varying environmental conditions T2 - The International Conference on Computational \& Experimental Engineering and Sciences PY - 2009 VL - 12 IS - 2 SN - 1933-2815 AB - Modal identification is essential in structural health monitoring (SHM) because that the modal parameters are often used for model updating and damage detection. However, in practical situations, the variation of environmental conditions (e.g. temperature, temperature gradients, humidity, etc.) will impede the reliability of modal identification. In this paper, firstly, the relation of frequency change and variation of environment temperature of space structure is investigated. Then, a structural state assessment method by combing autoregressive moving average (ARMA) and PCA is proposed. The acceleration data from China National Aquatics Center is employed as an example. The results show that variation of frequencies with increasing of temperature and wind velocity is not notable. That is because the temperature difference and velocity variation are little. KW - DO - 10.3970/icces.2009.012.065