Comparison of hand laid-up tape and filament wound composite cylinders and panels with and without impact damage

The results of this experimental comparison of filament wound control (unimpacted) cylinders loaded to failure in axial compression indicates that one fiber cross-over location has no effect on the failure mode or strain in thick walled filament wound graphite-epoxy specimens with stacking sequence (plus or minus 45/90) sub 3s. A comparison between filament wound and hand laid-up tape control cylinders indicates that there is little or no difference in the response of cylinders constructed by using two different fabrication methods, however, unimpacted panels with many fiber cross-overs fail at up to 15 percent lower strains than panels with no fiber cross-overs. A comparison of samples subjected to low speed impact damage prior to compressive loading indicates that impact damage reduces the strain at failure by over 60 percent in tape and filament wound graphite-epoxy cylinders and in tape flat panels. The presence of fiber cross-overs was observed to reduce the strength of filament wound impact-damaged panels, but to have no significant effect on the strength of filament wound impact-damaged cylinders.