Nondestructive damage detection in deteriorated girders using changes in nodal displacement

Abstract

The use of static and dynamic responses as inputs in the evaluation procedures of concrete structures has been discussed for many years. With the aim of contributing to efficient structural health monitoring approaches, the present study attempts to develop an estimation method that utilizes only displacement data for detecting structural damage. The approach is based on the correlation between structural damage and variations in measured responses. Specifically, two new damage indicators—displacement assurance criterion (DAC) and displacement-based index (DBI)—are introduced and employed in numerous scenarios to determine damage properties. Parametric studies are performed by a finite-element analysis to verify the correlation of DAC with increasing deterioration and the sensitivity of DBI for identifying the location of damage. In addition, the influence of parameters that affect the accuracy of the proposed methods, such as number of measurements and location of observation points, is also examined. The results demonstrate that DAC can properly indicate the occurrence of degradation in structures and DBI can be utilized as a suitable pointer for damage localization.