Abstract:

The traditional time-domain analysis method was improved to study the dynamic behavior identification of the concrete bridge structure under environmental excitation. Applying the combination of the natural excitation technique and the eigensystem realization algorithm, a finite element numerical simulation was performed for the dynamic behavior identification of a pre-stressed concrete continuous beam bridge under simulating wind load excitation. The results were validated comparatively using the combined algorithm of random decrement technique and Ibrahim time domain technique as well as the finite element modal analysis. The simulation results show that the wind load as the most common environmental excitation can be used effectively to identify the modal parameters of the concrete bridge. The results identified by the combination of the natural excitation technique and the eigensystem realization algorithm are pricise enough for the concrete bridge, providing an effective support for the structure health monitoring and structure design.

Key words: bridge engineering, dynamic behavior, time-domain analysis, finite element numerical simulation,  , wind load excitation