Full field strain measurement of braided composite structures

Braided composites consist of continuous fibers embedded in a matrix. Braid mechanical properties are influenced through selection of matrix and fibers and by modifying the braid manufacturing process. Control of braiding parameters allows for tailorable mechanical properties. The objective of this work is to utilize full-field strain measurement approaches for the assessment of braided composite structures. Two full-field strain measurement methods will be utilized (1) Three Dimensional Digital Image Correlation- 3D DIC and (2) Digital Volume Correlation-DVC. 3D DIC is an optical stereo camera based strain measurement method while DVC is an x-ray based tomographic approach that allows for volumetric strain measurement. The two correlation methods utilized in this study provide both surface and volumetric strain data for braided composite structures. The approaches outlined in this work are a critical first step towards better understanding the internal and external deformation and strains that occur within braided composite structures and results will be used towards analytical and numerical models for braided composites.