Research On Mechanical Properties Of Composite Laminates With Embedded Optical Fiber

Smart composite, which is to introduce optical fiber senor into fiber-reinforced composite, hasdrawn great attention both at home and abroad. This new material has great advantages in monitoringfatigue and damage inside the composite, which is of great importance in real-time structural healthmonitoring and structure life forecasting. Although, ideally, embedded optical fiber serves to perceivesurrounding changes, it should be subjected to load inevitably. Besides, after optical fiber embedded,continuity and integrity of original material is impaired. Therefore, it is of great importance to studythe mechanical interrelationship between embedded optical fiber and composites.In this paper, carbon-fiber-reinforced composite laminates with optical fiber embedded wasstudied as an example both through experiment and Finite Element (FE) analysis for the investigationof the mechanical influence of the embedded optical fiber on the composite. The main achievementsare described as followed:(1) For the purpose of studying the influence of the optical fiber on the microstructure ofcomposite laminates, the interface between the embedded optical fiber and the composite laminateswere investigated using an electron microscope.(2) In order to evaluate the effect of optical fiber on mechanical properties of compositelaminates, a series of tensile tests and bending tests of composite laminates with and withoutembedded optical fiber were performed.(3) In view of the different diameter, quantity and location of optical fiber and the different typesof composite laminates, the geometrical relationship between the optical fiber and the compositelaminates was discussed according to the microstructure study. Different FE analysis models of thecomposite laminates with embedded optical fiber under the tensile, bending and compressive loadwere established for mechanical properties analysis using FE method. The accuracy of the FE analysiswas verified by comparing the experimental results with the theoretical results.(4) The FE analysis was performed on a new model, in which the interface element was chosenfor simulating the interface inside the composite laminates, in order to study the damage of theinterface under bending load in detail.