The load-deformation behavior of braided ±45-deg graphite/epoxy cylinders with integrally-formed braided and machined holes has been investigated. Axial tension or compression was applied to the cylinders via pairs of diametrically-opposed holes at the mid-length of the specimens. Pin-joint bearing tests were conducted on another set of specimens. Strains were measured around the hole and at a range of locations along the cylinder length and circumference. The strain concentration effects and failure modes are illustrated and discussed. Integrally-formed braided holes are seen to provide an in creased joint bearing strength compared with machined holes in the composite materials studied.
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