FUNDAMENTAL STUDY ON IMPROVEMENT OF STRUCTURAL INTEGRITY ASSESSMENT BY USING HIGHER MODE RESPONSE

Abstract

 The damage level of railway structures after earthquakes was judged by the change in eigenvalues of the first-order modes. In this study, we investigated the improvement of this method for the structural integrity assessment. At first, an eigenvalue analysis was carried out by changing the damage location of the structure. From this analysis, the relationship between the location of damage and the change in natural frequencies including higher-order modes was evaluated. In the case of the RC piers, damage to the piers has a significant effect on the first mode natural frequencies. On the other hand, damage to the foundation has a significant effect on the higher mode natural frequencies. In other words, it is possible to identify the location of damage to a structure by understanding the change in natural frequencies of the higher modes.