Crack detection of composite shell under lateral loading using FBG sensor

Abstract

The studies on the non-destructive testing methods of the composite materials are very important for improving their reliability and safety. If the generation, growth, and accumulation process of these defects within composite materials can be revealed by a nondestructive test, the strength and residual life can be evaluated more accurately. FBG (fiber bragg grating) sensors have attracted much interest owing to the important advantages of optical fiber sensing. The sensor type of using FBG is mainly used in order to detect the crack of composite structures in real time. Compared to conventional electronic sensors, fiber-optical sensors are known for their high resolution and high accuracy. Futhermore, they offer important advantage such as immunity of electromagnetic interference, and electrically passive operation. In this paper, the signal characteristics of FBG sensors were analyzed under the buckling test of composite plate. Also, the wavelength variation of FBG sensor was measured and its strain was calculated. Calculated strains were compared with those by the finite element analysis. Copyright © (2012) Asian-Australasian Association for Composite Materials (AACM).