Abstract
In order to achieve the effective management of huge number of existing railway bridges, it is important to estimate the structural performance estimation based on simple measurement. This study proposed two, MCMC based inverse analysis and modal identification based simple evaluation, methods by employing the beam dynamics theory to be able to estimate not only vibration properties but also displacement and impact factor that are also used in the design. The numerical calculations revealed that the inverse analysis can estimate accuracy more than existing identification methods such, as FFT and so on. Although interaction effect with passing train has a dominant influence on the estimation accuracy, the proposed method can estimate the maximum displacement within 2% error based on acceleration. By application to the acceleration measured on actual bridges, estimation errors on the maximum displacement were -3% to +6% in case of the proposed inverse analysis method.