Multi-Axle Moving Train Loads Identification on Continuous Bridge from Bridge Displacement Responses

Abstract

A new method for multi-axle moving train loads identification on continuous bridge is presented in this paper. In order to improve the accuracy and efficiency for moving loads identification, both cubic spline interpolation technique and dynamic displacement influence line technique were employed. The time history displacements of the measurement stations under unit force were calculated with cubic spline interpolation technique based on the finite element model of the bridge. The dynamic displacement influence line was obtained to be used for identifying the moving train loads with simulated annealing genetic algorithm by minimizing the errors between the measured displacements and the reconstructed displacements from the moving train loads. A series of comparative studies were carried out to investigate effects of different span numbers with the same length, different length with the same span number and measurement noise on the proposed method. The result shows that the proposed method is an accurate and efficient method for multi-axle moving train loads identification on continuous bridge.