Vibration-Based Damage Localization in Flexural Structures Using Normalized Modal Macrostrain Techniques from Limited Measurements

Abstract

This article presents damage locating indices based on normalized modal macrostrain (MMS) as improvement on the typical curvature-dependent methods. Vulnerability to noise and the use of numerical differentiation procedures are the key factors for the poor performance of many curvature-dependent methods using displacement mode shapes. Whereas dynamic distributed strain measurement data from long-gauge FBG sensors have significantly improved the performance of many damage identification methods, the sensitivity to local damage diminishes as the gauge length increases. The proposed model-free damage identification techniques based on normalized MMS vectors are successfully implemented to locate damage in beam-like structures through numerical simulations and experimental verifications. The unique advantages of the techniques are their simplicity, robustness to noise, ability to precisely identify small damage extents, and localize single and multiple damage states using limited measurable modes from few sensors.

Wavelet‐Based Detection of Beam Cracks Using Modal Shape and Frequency Measurements

“…When using the crack detection method based on vibration characteristics it is still difficult to predict the crack locations and depths robustly (Li and Wu 2007, 2008a,b; Moaveni et al, 2008; Cruz and Salgado, 2009; Adewuyi and Wu, 2011; Li et al, 2011; Figueiredo et al, 2011; Talebinejad et al, 2011). The model‐based crack detection methods associated with frequency measurement have drawn special attention.…”

Comparative Studies of Steel, Bamboo and Rattan as Reinforcing Bars in Concrete: Tensile and Flexural Characteristics

“…However, aside the environmental and operational condition, the constituent materials accounting for the increasing cases of structural deficiency and functional obsolescence are recorded in the built environment (Adewuyi et al [1] [2], Adewuyi and Wu [3]). …”

3D displacement measurement model for health monitoring of structures using a motion capture system

“…Reduced stiffness resulting from damage to members and loosening of connections can be detected through changes in the structural dynamic response. The safety of the structure can be assessed using acceleration data (Adewuyi and Wu 2011;Figueiredo et al 2011;Talebinejad et al 2011;Osornio-Rios et al 2012;Qiao et al 2012;Xiang and Liang 2012;Jiang et al 2012). Accurate assessment of safety, however, is difficult, due to the analytical limitation and the fact that numerous assumptions must be made in the assessment process, considering the inherent uncertainties of large and complex civil structures.…”