Discrete modeling of fiber reinforced composites using the scaled boundary finite element method

•Development of a versatile method to model fiber reinforced composites: (a)arbitrary fiber distribution. (b) arbitrary volume fraction. (c) no interface elements or constraints.•Efficient mesh generation for matrix and aggregates using a quadtree/octree algorithm.•Robust analysis of the stress distribution and effective material properties of fiber reinforced composites. A numerical method for the discrete modeling of fiber reinforced composites based on the scaled boundary finite element method (SBFEM) is proposed. A unique feature of this method is that the meshes of the matrix, aggregates, in general volumetric entities can be generated independently of the fibers which are treated as truss elements. To this end, a novel embedding method is developed which connects the mesh of the matrix consisting of scaled boundary polytopes to the fibers. This approach ensures that conforming matrix and fiber meshes are achieved. The computed stiffness matrices for both components are then simply superimposed using the nodal connectivity data. Since volume elements can be intersected by fibers at arbitrary locations, it is of paramount importance to be able to generate polytopal elements which is one unique feature of the chosen SBFEM implementation. An advantage of this procedure is that no interface constraints or special elements are required for the coupling. Furthermore, it is possible to account for random fiber distributions in the numerical analysis. In this contribution, a perfect bonding between the matrix and fibers is assumed. By means of several numerical examples, the versatility and robustness of the proposed method are demonstrated.