Experimental characterisation of random field models for CFRP composite panels

The accuracy of reliability analysis of structures made up of CFRP composites rely on the quantification of the uncertainties associated with composite material properties. This study focuses on the experimental characterisation of random field models for the material uncertainties. As a first step, a number of experimental tests on identical samples have been conducted as per ASTM standards. Assuming second order random fields to be appropriate for modelling the uncertain variations along the spatial extent in the macro-scale, statistical tests have been carried out to examine the suitability of some commonly used models for the probability density function for the various mechanical properties of the material. The spatial correlations observed from experimental tests have been compared with some of the commonly used correlation functions and suitable empirical models have been proposed. Finally, the importance of appropriate modelling of the parameters has been highlighted through a numerical example.