NUMERICAL ESTIMATION OF MECHANICAL CHARACTERISTICS OF AN UNIDIRECTIONAL COMPOSITE PLY AND STUDY OF THE SOLUTION CONVERGENCE

The available micromechanics theory allows for fast estimations on certain macromechanical properties of composite structures. Despite this, the classical methods do not provide accuracy enough in the determination of all the mechanical properties of an anisotropic material (such as transverse elastic and shear moduli or Poisson coefficients). This study presents an analysis of a generic configuration for the microstructure of a composite ply dedicated to the determination of its mechanical properties with a higher accuracy with respect to the theoretical formulation. The aim of this research is also to characterise the mechanical properties of the material further than the used theory allows. All the numerical experiments have been designed and performed with the smallest possible geometry that guarantees an acceptable precision of the solution. This optimisation has been a primary concern throughout the research. The numerical modelling had as a central piece a cubic geometry with a model of the corresponding fibre and matrix. This geometry could be easily extended in a pattern in order to study more extensive configurations. The numerical model consisted on solid elements with all boundary conditions applied as displacements. The numerical testing configurations have been designed to emulate the hypotheses assumed in the theoretical models. In order to ensure that the obtained results were consistent several tests have been performed. In this category convergence tests have been done to ensure that the used meshing was suitable enough. Moreover, the results have been analysed together with the theoretical solutions available in the bibliography whenever possible to validate the numerical arrangement and hypotheses assumed.