CRASHWORTHINESS CHARACTERISTICS OF GFRP OVERWRAPPED PVC COMPOSITE TUBES

Abstract

This thesis investigates the effect of various factors on the crashworthiness characteristics of GFRP overwrapped PVC tubes. PVC tubes overwrapped in GFRP at four different fiber orientations, 45°, 55°, 65°, and 90°, respectively, were subjected to quasi-static axial compression tests. For the GFRP/PVC samples of different fiber orientations with standard circular tube geometry, load-bearing capacity, crush force efficiency, and energy absorption capability generally improved with increasing fiber orientation. The first proposed design change to the conventional circular composite tube geometry increased specific energy absorbed by an average of 32.52%, while load-bearing capacity was also maintained. However, it also resulted in a noticeable decrease in crush force efficiency For the second proposed design change to the conventional circular composite tube geometry, the advantage of increased specific energy absorption, seen for the first design change, was retained. At the same time, a sizeable 43.82% average increase in crush forc efficiency was also observed. The combination of the two proposed design changes as compared to chamfer triggers was proven to be comprehensively more effective. Finally, foam cores of four different geometries were used to fill the composite tube with the best performance from all previous tests. As compared to the core-less samples, the composite tubes with cores had noticeably higher load-bearing capacity and energy absorption capabilities. However, their crushing failure was not as stable.