Curvature rate approach to the evaluation of the stiffness distribution in plate-like structures

A procedure for identifying the bending stiffness distribution in plate-like structures is presented. The algorithm is based on the correlation between a parameter called curvature increased factor (CIF) and the bending stiffness of the plate, D. Accurate correlation can be achieved only by considering the effect of the redistribution of internal forces and moments due to the damage on the curvature distribution. In order to achieve this goal, the study offers an iterative procedure, which eliminates the effect of the moment redistribution from the CIF and eventually correlates accurately between CIF and D. The curvature rate is evaluated from the displacement mode shape using a 2D smoothing technique. The procedure takes into account the presence of random errors and the limited number of measured nodes. The procedure's effectiveness, reliability, and range of applicability are demonstrated using numerical examples.