Effect of trigger configuration on the crashworthiness characteristics of natural silk epoxy composite tubes

In the current study, the quasi-static compression test over natural silk epoxy composite tubes was performed using two different trigger mechanisms. The natural silk epoxy composite tubes used in this study consisted of 12 layers of woven natural silk as reinforcement and a thermoset epoxy resin as matrix. The natural silk epoxy composite tubes had lengths of 50 mm, and they were associated with external triggers, including four steel pieces located on the downside flat plate fixture and a plug trigger. The failure modes of the natural silk epoxy composite tubes were investigated using representative photographs taken during the quasi-static compression test. In addition to the load-displacement graphs, the crashworthiness characteristics of the natural silk epoxy composite tubes were exported. The results showed that the four-piece trigger mechanism changed the manner in which failure progressed i.e. from catastrophic to progressive. Plug trigger caused a significant reduction in load carrying capacity and energy absorption capability of specimens. The four-piece trigger retained energy absorption capability of specimens similar to the non-triggered ones, while both the reduction of peak load and increase in crash efficiency of these were observed to be significant.