On the study of element modal strain energy sensitivity for damage detection of functionally graded beams

Abstract

In this paper, a modeling framework based on element modal strain energy sensitivity is developed for identifying damage of functionally graded beams. The element damage equation set of functionally graded Euler-Bernoulli beam is established built on element modal strain sensitivity and the rate of change of element modal strain energy from healthy to damage. The Tikhonov regularization algorithm incorporated with the generalized cross validation is used to solve the reliability problem of damage equation set. Numerical illustrative examples contain a simply supported and continuous functionally graded Euler-Bernoulli beams are considered to demonstrate the performance of the method. The influences of gradient index, damage extent, mode shape and noise level are investigated respectively. Damage results imply that the proposed method can give a valid way to accurately detect the damage of beam-like structures, also has excellent resistance to measurement noise.