Damage level assessment using DAD method and model updating

Aging infrastructure, particularly bridges, requires reliable methods for assessing structural integrity. Structural Health Monitoring (SHM) provides a proactive approach to damage detection and maintenance, but traditional methods often lack the capability to assess the severity of detected damage. This paper introduces an enhancement to the Deformation Area Difference (DAD) method, specifically designed to enable Level 3 SHM for damage severity assessment. Traditionally, the DAD method focuses on detecting and localizing damage by analyzing the deflection of structures under static loads, but it does not provide a means for quantifying damage severity. To address this limitation, a model updating (MU) technique is integrated into the DAD method, allowing for assessment of the severity of localized damage. The method involves deriving curvature differences from the deflection data and applying an inversion-based MU algorithm to quantify the extent of structural damage. The research includes numerical simulations and experimental investigations, showcasing the potential of the enhanced approach for real-world applications. The results highlight the potential of the enhanced DAD method for damage level assessments while maintaining computational efficiency. However, real-world applications remain influenced by noise and deformation magnitudes, requiring further refinement. These findings suggest that the enhanced method has potential for SHM applications, particularly in assessing structural integrity and guiding maintenance decisions in real-world applications. • Applies a low-complexity inversion-based model updating technique for Level 3 SHM. • Enables quantification of bending stiffness reduction for damage severity. • Mitigates missing measurement points using nonlinear regression for better accuracy. • Investigates and reduces noise-induced errors in damage level estimation. • Demonstrates potential of the method in detecting damage in real bridge structures.