A numerical study on the axial crushing response of hybrid pultruded and ±45° braided tubes

A comprehensive numerical investigation was carried out to evaluate the response and energy absorbing capacity of hybrid composite tubes made of unidirectional pultruded tube over wrapped with +/- 45 degrees braided fiber-reinforced plastic (FRP). The numerical simulation characterized the crushing behaviors of these tubes subject to both quasi-static compression and axial dynamic impact loadings. Two types of braided FRP, glass and carbon fibers, were considered. Parametric studies were also conducted to examine the influence of the tube's length, thickness and type of braid, as well as the loading conditions on the crushing behavior of the tubes. It was observed that although the pultruded tube, which had the highest stiffness among the tubes considered, produced the highest magnitude of energy absorption capacity, it exhibited a non-symmetric failure mode followed by a longitudinal splitting. On the other hand, the hybrid tubes exhibited a more desirable, accordion type failure mode, therefore they are considered to be more suitable candidates as energy absorbing structural members in service conditions. (C) 2006 Elsevier Ltd. All rights reserved.