The Energy-Absorbing Characteristics of Tubular Structures With Geometric and Material Modifications: An Overview

Typical example of the progressive buckling mode and resultant axial load-displacement curve of a thin-walled square tube (41)

Imperfections in the tube corners as used by Schriever and Helling (19)

Shape of (a) full dent and (b) half-dent introduced into the aluminum tube specimen (47)

Deformed aluminum tubes with schematic of the locations of triggering dent (47)

Symmetric axial crush response mode—ductile metallic alloy: axial crush specimen and undeformed tube (48)

A typical load-displacement characteristic of aluminum alloy corrugated tubes (59)

Symmetric deformation of dynamically loaded predented square specimens. Dent depth increases from left to right (60).

Quasistatically crushed square tubes with opposing parallel cylindrical indentations (62) (depth of indentations increases from left to right)

Quasistatically collapsed square tubes with opposing dished indentations (62). (The indentations were induced with a hemispherical indenter of radius 100mm and the depth of indentations increases from left to right).

Quasistatically crushed square tubes with two opposing holes (62) (diameter of the holes increases from left to right—it appears that the size of the first lobe decreases with increasing hole diameter until tearing occurs)

The effect of the diameter of the holes on ultimate buckling load of specimens with opposing combined imperfections (62) (indentations depth of 3.5–4mm, diameter of hole increases from left to right, G2 has no hole)

The effect of the depth of dished indentations on ultimate buckling load of specimens with opposing combined imperfections (62) (hole diameter, 32mm; depth of indentations increases from left to right)

Collapse profiles and load-deformation history of spot-welded top-hat sections after impact testing at 10m∕s(79)

Test foam-filled specimen geometry and typical material behavior (82)

Deformation behavior of square and circular extrusions as a function of foam filler density (95-96)

Empty, monotubal filled, and bitubal square crushed specimens (102)

Square, hexagonal, and octagonal monotubal crushed specimens (102)

Photographs of sectional front and back views of crushed PVC tubes filled with mixed wood sawdust (107)

Typical collapse modes of bare brittle metal and plastic metal tube (122): (a) fragmentation mode of a brittle metal tube; (b) concertina (axisymmetric) mode of a plastic metal tube; (c) diamond (asymmetric) mode of a plastic metal tube

Failed hybrid tubes obtained from the axial crushing test (125): (a) 0deg ply orientation composite tube, (b) 90deg ply orientation composite tube, (c) 0deg∕90deg ply orientation composite tube, and (d) ±45deg ply orientation composite tube