Bridge Damage Analysis Using Operational Modal Analysis

• Published in: Journal of Vibration Engineering & Technologies Vol. 12; no. 7; pp. 7799 - 7814
• Main Authors: Barbieri, Nilson, de Sant’Anna Vitor Barbieri, Lucas, Legat, Jacqueline Terre, de Lima, Key Fonseca, de Sant’Anna Vitor Barbieri, Gabriel
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01.10.2024
• Subjects: Acoustics; Control; Dynamical Systems; Engineering; Engineering Acoustics; Original Paper; Vibration; Energy parameter; OMA; Damage; Bridge; Trend line
• ISSN: 2523-3920; 2523-3939
• DOI: 10.1007/s42417-024-01328-w

Introduction The dynamic analysis of complex structures subject to excitations that are difficult to quantify or measure can be conducted using operational modal analysis procedures. The experimental behavior can be validated using results from numerical simulations of mathematical models. Materials and methods This work’s main objective is to develop an automated operational modal analysis (OMA) system. The analyses will be developed using a bridge prototype described in the literature. The structure’s geometry resembles the main span of the iconic Story Bridge of Brisbane. The identification procedure contemplated dynamic tests and, development, and validation of mathematical models obtained by the finite element method. The system excitation is obtained with moving loads (small vehicles moving over a bridge). The automatic system was validated by comparing the numeric and experimental natural frequencies and mode shapes for the original system and for the same system with intentional damage induced by modifying torque in screws connecting metallic joints. Results An automatic operational modal analysis system was validated by comparing experimental modal parameters obtained in a metallic bridge prototype and numerical data obtained by computer simulation of a mathematical model. The dynamic behavior was evaluated for the system with and without structural modifications. It was possible to identify variations in the modal parameters for the damaged system. It was also possible to identify possible damage locations using an energy parameter based on filtered signal trend lines. Conclusions The automatic modal analysis system presented was efficient in obtaining the modal parameters of systems with and without damage, as well as in locating the damage.