An effective materials by design approach has been detailed and exercised to expedite the development and insertion of 3D fabrics and composites in various structural and protective systems. Previous research efforts have identified a family of advanced, 3D woven composite reinforcements which show promise for multiple applications. These multi-layer, integrally woven designs have significantly improved through-thickness properties. The higher through-thickness tensile strengths are a result of additional fibers, oriented in the z-direction, which must be fractured for ultimate failure of the structure. On the other hand, the through thickness shear strengths are strongly dependent on the matrix cracking and yarn-to-yarn interface debonding within the 3D fiber composites. Consequently, properly designed 3D reinforcements can significantly reduce the propagation of delamination commonly induced by severe lateral impact, and thus can greatly enhance the damage tolerance of composite structures. The proposed approach uses computational methods, rather than experimental observations, to generate complex 2D and 3D composite architectures at the filament level using the digital element approach. The fiber filament model is then idealized as a solid yarn model and meshed for finite element analysis using commercial software. Micromechanics analysis was then used to model the progressive failure response of the composites subjected to loading at various quasi-static and dynamic strain rates, with the results validated through experimentation. Analysis of constituent properties and weave architecture was completed and used to make design recommendations for improved material response for composites subjected to ballistic impact. This approach provides a potential for drastically reducing the design cycle time by eliminating the need to fabricate each design architecture, allowing for reduced cost as well as an increase in the design scope over multiple variations in weave pattern.
