Method of assessment of mechanical characteristics of quasi-isotropic composite laminates using experimental data from fiber- optic strain sensors

The problem of analysis and prognosis of mechanical behavior of advanced composite materials and structures during their design, manufacturing and exploitation is urgent and attracts attention of many researchers. One of the most promising areas in the field of monitoring of the state of composite structures in the process of their exploitation is connected with creation of smart materials and smart systems based on the sensor elements. The real-time data about the structure state under the subsequent analysis can be used both for monitoring the mechanical state of the structures and for refining the mathematical models for the fracture processes prediction. The purpose of this work is to develop a combined computational and experimental methodology for estimating the mechanical characteristics of structures made of polymer composite materials (PCM). The computational component of the technique provides numerical simulation of mechanical behavior during quasistatic deformation of structures made of PCM. The experimental component is based on the measurement of deformations by fiber-optical strain sensors with Bragg gratings (FBG sensors) embedded in PCM. To refine the model parameters in accordance with the information received from the FBGs an algorithm is proposed, according to which the inverse problems are solved in order to ensure that the numerical and experimental results coincide with the specified accuracy. The implementation of the algorithm is demonstrated on the numerical example.