Modal parameters identification of light rail bridges

Abstract

One of important aspect in Structural Health Monitoring System (SHMS) is the initial condition of the structure. This paper studies the initial condition of light rail train (LRT) bridges before officially operated. There are four bridges to be evaluated, consists of three simple supported bridges and one continuous bridge. Data measurement was using tri-axial accelerometer EZDYN with a train-set as the dynamic loading source. The modal parameters are obtained by means of operating modal analysis (OMA) in time domain. Three methods are simulated, that are ARMA, ITD and SSI. The data processing applied shows that all three methods give satisfactory results that confirm each other, for both natural frequencies and vibration modes.