Compression performance of composite stiffened panel after stiffener repair

Subjected to compressive load, stiffener injury often causes serious failure of stiffened composite panels. In consideration of stiffener-skin debonding, delamination in web and damage to upper flange, corresponding repair programs were designed and necessary specimens were manufactured. In order to ensure a uniform compressive load during experiment, test fixture for composite stiffened panel was designed and fabricated, containing two slots to fix the stiffened panel and four guides to ensure the vertical loading direction. All the experiments that were taken using that fixture show the influences of different repair parts, different repair methods to the mechanical properties of stiffened panels are different. Finite element analysis shows that buckling mode, failure mode of stiffened panel and skin-stiffener glue injury are both influenced by repair programs.