A damage detection approach based on the distribution of constraint forces predicted frommeasured flexural strain

Abstract

Changes in flexural strain are good indicators for locating damage in structures. Despitesuch promise, flexural strain data measured at a few positions do not provide enoughinformation to detect damage. However, they do become more effective if converted tovertical deflection data. Considering the relationship between measured flexural strainand vertical deflection as a constraint, this work provides a method to detectdamage based on the distribution of flexural curvatures and constraint forcesalong a structural beam-member. The constraint forces are forces required fordescribing the flexural shape of the damaged beam under static and dynamicloadings. It is illustrated in two applications that the proposed constraint forcemethod is more effective than the displacement curvature method in detectingmultiple areas of low-level damage and when considering noisy measured data.