A STUDY ON THE BEST CONVENTIONAL SHAPES FOR COMPOSITE REPAIR PATCHES

Resumo

Adhesively bonded repair patches are an excellent approach for repairing locally damaged

composite components. If correctly applied, fiber reinforced patches may restore/increment the me-
chanical response of damaged laminates without significantly increasing the structure’s mass or altering

its geometry. However, in order to take full advantage of this repairing technique, one must employ

patches with a minimal surface area and maximum efficiency in incrementing the strength of the compo-
nent. The present work aims to study optimum-based patch shapes for conventional repair geometries,

namely rectangular and elliptical. Shell Finite Elements models simulated a parent plate, a rectangular
flat laminate, with a central trespassing damage region. Unbalanced single-ply patches were modeled
on the upper surface of the damaged laminate. The patches efficiency was computed as its capability
in restoring the modal response of the repaired component to its undamaged configuration. Sequential
linear programming was employed alongside shell finite element models to obtain optimal geometrical
parameters for the patches shape. The study cases comported two different boundary conditions and two
stacking sequences. The optimum-based repair patches were defined regarding size and fiber orientation
angle.