3次元形状計測と実振動計測に基づくFEモデル精緻化のための橋梁振動特性の高精度推定手法

抄録

　　　This paper presents a method for identifying dynamic characteristics of a bridge using stochastic system identification and statistical analysis. In this study, three-dimensional shape of a truss bridge is obtained by 3D laser scanning and used for FE modeling. The initial FE model based on 3D measurement is validated and updated by comparing analytical dynamic characteristics of the FE model and the actual characteristics of the bridge estimated by stochastic system identification. Estimations of dynamic characteristics generally fluctuate under the influence of the environment in service state. In this study, distribution of the series of estimated frequencies is assumed as a Kernel distribution and significant frequencies such as natural frequencies are classified based on the probability density of estimations. The method stably provides accurate characteristics of the bridge under several excitation states.