Estimation of axial compressive strength of unidirectional carbon fiber reinforced plastic considering local fiber kinking

In this study, the global fiber kinking theory proposed by Budiansky and Fleck for the estimation of axial compressive strength of unidirectional carbon fiber reinforced plastic was modified for the localized fiber kinking problem. The deterministic mechanism of the compressive strength and kink-band width was interpreted using a graphical method. Carbon fiber reinforced plastic was manufactured from carbon fiber and epoxy matrix using prepreg and autoclave technology, and the axial compressive strength was measured. The nonlinear shear stress-strain curves of the composite and matrix were also measured using V-notched beam, in-plane shear, and torsion tests. The composite axial compressive strength and kink-band width were estimated based on the composite and matrix shear properties, respectively, and the estimated values were in good agreement with the experimental results.