Quasi-static and low-velocity impact behavior of the bio-inspired hybrid Al/GFRP sandwich tube with hierarchical core: Experimental and numerical investigation

Abstract

Abstract Sandwich tube structures bio-mimicking horsetail and human tendons offered significant improvement over traditional single and multi-cell tubular energy absorbers. The present research aims to investigate three manufactured hybrid multi-cell aluminum and GFRP sandwich tubes subjected to quasi-static and low-velocity axial compression . The crashworthiness characteristics and axial crushing failure mechanisms of sandwich tubes are discussed and compared with the quasi-static axial behavior of single Al and GFRP tubes. Further investigations, based on the validation of an FE model versus experimental results, using the commercial finite element code LS-DYNA, on the effects of material permutation and inner tubes diameter are perceived through the full-factorial approach of FE parametric study . The quasi-static results revealed that, packing the Al and GFRP tubes in the form of multi-cell sandwich tube generally improves the crushing patterns of individual hollow tubes. Moreover, the low-velocity response of the hybrid multi-cell sandwich tubes showed that the crushing response of the GFRP components despite AL ones depends significantly on the strain rate , where Al tubes undergo irregular diamond deformation. Eventually the results of bio-inspired hybrid multi-cell sandwich tubes indicate that incorporating more GFRP tubes provided an optimal crashworthy design and conduce to a broad range of applications within aerospace, transportation.