Publications

Uncertainty quantification and parameter study related to the analysis of a composite material loaded in four-point flexure

Nelson, Stacy M.; English, Shawn A.; Briggs, Timothy B.

Fiber-reinforced composite materials offer light-weight solutions to many structural challenges. In the development of high-performance composite structures, a thorough understanding is required of the composite materials themselves as well as methods for the analysis and failure prediction of the relevant composite structures. However, the mechanical properties required for the complete constitutive definition of a composite material can be difficult to determine through experimentation. Therefore, efficient methods are necessary that can be used to determine which properties are relevant to the analysis of a specific structure and to establish a structure's response to a material parameter that can only be defined through estimation. The objectives of this study deal with the computational examination of the four-point flexural characterization of a carbon fiber composite material. Utilizing a novel, orthotropic material model that is capable of predicting progressive composite damage and failure, a sensitivity analysis is completed to establish which material parameters are truly relevant to a simulation's outcome. Then, a parameter study is completed to determine the effect of the relevant material properties' expected variations on the simulated four-point flexural behavior. Lastly, the results of the parameter study are combined with the orthotropic material model to estimate any relevant material properties that could not be determined through experimentation (e.g., in-plane compressive strength). Results indicate that a sensitivity analysis and parameter study can be used to optimize the material definition process. Furthermore, the discussed techniques are validated with experimental data provided for the flexural characterization of the described carbon fiber composite material.