REAL-TIME TREND ESTIMATION OF DAILY FLUCTUATION BASED ON GNSS DISPLACEMENT OBSERVATION ON A STEEL TRUSS BRIDGE

Abstract

In this study, we applied a trend model, which is one of the statistical processing methods in order to eliminate the measurement error that is a problem in GNSS displacement observation of bridges. And we success to extract a periodic trend of the bridge deformation due to the daily temperature changes. In addition, in order to Implement the real-time monitoring, we applied a method of sequentially updating the parameters required for estimating the trend model each time data is obtained. As a result, we succeeded in estimating the trend in real time, which is almost the same as the smoothing result except. Besides, considering the mechanism of the trend model around time and the amount of expansion and contraction of the member due to temperature change, we applied the method of sequentially updating the model parameters. As a result, it was found that the estimated value of the trend model can be partially improved.