Local stresses in the reinforced plate with orthogonal systems of fibers. The homogenized strength criterion

•The three-layer plate provides us with complete information about the local stress–strain state in the multi-layer plate formed of an arbitrary number of layers.•The homogenized strength criterion for the fiber-reinforced plates exists and may be constructed numerically in the form of a computer procedure.•The homogenized strength criterion indicates the weakest element(s) of the plate.•The effective numerical procedure for the constructing homogenized strength criterion for the fiber-reinforced plates is proposed and the corresponding computer program is developed.•Failure surfaces are drawn for composite plate for the case of pure bending/torsion. In [1], the method of computation of local stress–strain state in the fiber-reinforced plate was presented. It was introduced the notion of the representative model for the multi-layer plates. It was demonstrated that the three-layer plate provides us with complete information about the local stress–strain state in the multi-layer plate formed of an arbitrary number of layers. In this paper, we construct the homogenized strength criterion (HSC) for the fiber-reinforced plates. In the general case, HSC is constructed in the form of a computer procedure. We develop the corresponding computer program. For the pure in-plane tension/shift or pure bending/torsion, 3-D failure surfaces may be drawn. We present the failure surface for the case of pure bending/torsion.