Energy absorption characteristics of E-glass/epoxy over-wrapped aluminum pipes with induced holes: an experimental research

Sci Rep. 2022 Dec 6;12(1):21097. doi: 10.1038/s41598-022-25679-0.

Abstract

The effect of inducing circular holes into aluminum wrapped with glass/epoxy (Al/GFRP) pipes was investigated. Intact and holed specimens were evaluated in quasi-static axial compression after being constructed using the wet wrapping procedure. The effect of the induced holes' parameters i.e., hole diameter (d), number of holes (n), the hole position to specimen height ratio (L/H), on the crashworthiness of Al/GFRP structures was investigated. Results indicated that the existence of the cutouts visibly affects the values of crushing parameters. Increasing (d) remarkably reduces the total absorbed energy (U) and enhances the crushing force efficiency (CFE) of Al/GFRP pipes. Introducing two holes in two opposite faces with keeping their location constant reduces initial peak crush force [Formula: see text], mean crush force [Formula: see text], and U of Al/GFRP pipes but increases CFE. As the hole location goes to the lower edge of the pipe i.e., L/H increases, U obviously increases. The specimens with 4 mm holes in one side at medium height and specimens with 12 mm holes on one side at L/H = 0.8 had the best crushing parameters, respectively. The adequate design of the induced cutouts in thin-walled constructions is valuable to enhance the crashworthy performance of engineering structures.