A delamination detection model for composite beams using PFRC sensor/actuator

Abstract

The presence of a delamination in a laminated composite structure can significantly change the behavior and dynamic characteristics of the structure. Hence, it is necessary and important to develop an effective method to identify the loci and sizes of delamination embedded in a laminated composite structure. In this paper, a one-dimensional dynamic analytical model is proposed to detect a single delamination embedded in a laminated composite beam using piezoelectric fiber reinforced composite (PFRC) sensor/actuator. Using the present model, the first three order frequencies, sensor charge output (SCO), normalized sensor charge output (NSCO) and their distributions along the beam can be predicted, when the beam system is excited by a PFRC actuator. The presence, locus and size of a delamination can be determined by comparing the SCO or NSCO distribution along the length for the beams with and without delamination. Then, a comparison of the first three order frequencies between the present analytical and finite element analysis models is conducted to validate the proposed model. Finally, an extensive numerical study is conducted using the present model to investigate the effects of major geometric parameters and electric field on the SCO and NSCO distributions.