Enhancing SHM with the extension of the deformation area difference method into the strain area difference method.

This study contributes to the fields of nondestructive testing (NDT) and structural health monitoring (SHM), which are pivotal for extending the service life of infrastructure and aligning with sustainability goals in construction. The study emphasizes an advanced application of the deformation area difference (DAD) Method, focusing on the comparative analysis of curvature lines derived from photogrammetry‐assisted deflection measurements and direct strain measurements. The novel strain area difference (SAD) method is presented. The research includes numerical simulations and practical experiments. A laboratory experiment with a steel beam demonstrates the method's effectiveness by comparing curvature lines from strain and deflection data. Additionally, an on‐site application on a composite bridge using photogrammetry and drone technology is described with a comparative numerical analysis. The investigations' results shed light on the potential of integrating diverse data sources in NDT/SHM practices. For instance, the integration of deflection measurements and strain measurements for SHM. The comparative analysis provides crucial insights into the accuracy and applicability of the DAD and SAD method in various structural scenarios, improving the precision of condition assessments in reinforced concrete structures. The findings have significant implications for the sustainable maintenance and operation of infrastructure. They support efficient decision‐making in the maintenance and repair of structures, contributing to their longevity and reducing the need for extensive interventions. They present a robust framework for decision‐making in predictive maintenance. [ABSTRACT FROM AUTHOR]