Development of a compressive failure model for carbon fiber composites and associated uncertainties

• Published in: Composites science and technology 2021-07, Vol.211, p.108855, Article 108855
• Main Authors: Camarena, Ernesto, Clarke, Ryan J., Ennis, Brandon L.
• Format: Article
• Language: English
• Subjects: Buckling; Carbon fibers; Carbon fibres; Composite materials; Compressive strength; Compressor blades; Fiber composites; Fiber reinforced composites; Fiber reinforced plastics; Fiber reinforced polymers; Finite element analysis; Finite element analysis (FEA); Finite element method; Interfacial shear strength; MATERIALS SCIENCE; Mathematical models; Misalignment; Pultrusion; Strength; Structural composites; Studies; Tensile strength; Uncertainty; Wind turbines
• ISSN: 0266-3538; 1879-1050
• DOI: 10.1016/j.compscitech.2021.108855

An approach to increase the value of carbon fiber for wind turbines blades, and other compressive strength driven designs, is to identify pathways to increase its cost-specific compressive strength. A finite element model has been developed to evaluate the predictiveness of current finite element methods and to lay groundwork for future studies that focus on improving the cost-specific compressive strength. Parametric studies are conducted to understand which uncertainties in the model inputs have the greatest impact on compressive strength predictions. A statistical approach is also presented that enables the micromechanical model, which is deterministic, to efficiently account for statistical variability in the fiber misalignment present in composite materials; especially if the results from the hexagonal and square pack models are averaged. The model was found to agree well with experimental results for a Zoltek PX-35 pultrusion. The sensitivity studies suggest that the fiber packing and the interface shear strength have the greatest impact on compressive strength prediction for the fiber reinforced polymer studied here. Based on the performance of the modeling approach presented in this work, it is deemed sufficient for future work which will seek to identify carbon fiber composites with improved cost-specific compressive strength. [Display omitted]