This two-part article reports the results of experimental and numerical works conducted on the energy absorption characteristics of thin-walled square tubes with multiple circular hole discontinuities. Part I presents the experimental tests in which dynamic and quasistatic axial crushings are performed. The mild steel tubes are 350 mm in length, 50 mm wide, and 1.5 mm thick. Circular hole discontinuities, 17 mm in diameter, are laterally drilled on two or all four opposing walls of the tube to form opposing hole pairs. The total number of holes varies from 2 to 10. The results indicate that the introduction of holes decreases the initial peak force but an increase in the number of holes beyond 2 holes per side does not further significantly decrease the initial peak force. The findings show that strategic positioning of holes triggers progressive collapse hence improving energy absorption. The results also indicate that the presence of holes may at times disrupt the formation of lobes thus compromising the energy absorption capacity of the tube. In Part II, the finite element package ABAQUS/EXPLICIT version 6.4–6 is used to model the dynamic axial crushing of the tubes and to investigate the action of the holes during dynamic loading at an impact velocity of 8 m/s.

1.
Lu
,
G.
, and
Yu
,
T.
, 2003,
Energy Absorption of Structures and Materials
,
Woodhead
,
Cambridge
.
2.
Abramowicz
,
W.
, 2003, “
Thin-Walled Structures as Impact Energy Absorbers
,”
Thin-Walled Struct.
0263-8231,
41
, pp.
91
107
.
3.
Langseth
,
M.
, and
Hopperstad
,
O. S.
, 1996, “
Static and Dynamic Axial Crushing of Square Thin-Walled Aluminium Extrusions
,”
Int. J. Impact Eng.
0734-743X,
18
(
7–8
), pp.
949
968
.
4.
World Health Organization and World Bank
, 2004, “
World Report on Road Traffic Injury Prevention
,”
Prevention
,
World Health Organization
,
Geneva
.
5.
Cheng
,
Q.
,
Altenhof
,
W.
, and
Li
,
L.
, 2006, “
Experimental Investigations on the Crush Behaviour of AA6061-T6 Aluminium Square Tubes With Different Types of Through-Hole Discontinuities
,”
Thin-Walled Struct.
0263-8231,
44
, pp.
441
454
.
6.
Abramowicz
,
W.
, and
Jones
,
N.
, 1984, “
Dynamic Axial Crushing of Square Tubes
,”
Int. J. Impact Eng.
0734-743X,
2
, pp.
179
208
.
7.
Arnold
,
B.
, and
Altenhof
,
W.
, 2004, “
Experimental Observations on the Crush Characteristics of AA6061 T4 and T6 Structural Square Tubes With and Without Circular Discontinuities
,”
Int. J. Crashworthiness
1358-8265,
9
(
1
), pp.
73
87
.
8.
Tarigopula
,
V.
,
Langseth
,
M.
,
Hopperstad
,
O. S.
, and
Clausen
,
A. H.
, 2006, “
An Experimental and Numerical Study of Energy Absorption in Thin-Walled High-Strength Steel Sections
,”
Int. J. Impact Eng.
0734-743X,
32
(
5
), pp.
847
882
.
9.
Abramowicz
,
W.
, and
Jones
,
N.
, 1997, “
Transition From Initial Global Bending to Progressive Buckling of Tubes Loaded Statically and Dynamically
,”
Int. J. Impact Eng.
0734-743X,
19
(
5–6
), pp.
415
437
.
10.
Montanini
,
R.
,
Belingardi
,
G.
, and
Vadori
,
R.
, 1997, “
Dynamic Axial Crushing of Triggered Aluminium Thin-Walled Columns
,”
30th International Symposium on Automotive Technology & Automation
, Florence, Italy, Jun. 16–19, pp.
437
444
.
11.
Chung Kim Yuen
,
S.
, and
Nurick
,
G. N.
, 2008, “
The Energy Absorbing Characteristics of Tubular Structures With Geometric and Material Modifications: An Overview
,”
Appl. Mech. Rev.
0003-6900,
61
(
2
), p.
020802
.
12.
Langseth
,
M.
, and
Hopperstad
,
O. S.
, 1997, “
Local Buckling of Square Thin-Walled Aluminium Extrusions
,”
Thin-Walled Struct.
0263-8231,
27
(
1
), pp.
117
126
.
13.
Marshall
,
N. S.
, and
Nurick
,
G. N.
, 1998, “
The Effect of Induced Deformations on the Formation of the First Lobe of Symmetric Progressive Buckling of Thin Walled Square Tubes
,”
Structures Under Shock and Impact (SUSI 98)
, Thessaloniki, Greece, Jun. 24–26,
N.
Jones
,
D. G.
Talaslidis
,
C. A.
Brebbia
, and
G. D.
Manolis
, eds., pp.
155
168
.
14.
Gupta
,
N. K.
, and
Gupta
,
S. K.
, 1993, “
Effect of Annealing, Size and Cut-Outs on Axial Collapse Behaviour of Circular Tubes
,”
Int. J. Mech. Sci.
0020-7403,
35
(
7
), pp.
597
613
.
15.
Lee
,
S.
,
Hahn
,
C.
,
Rhee
,
M.
, and
Oh
,
J.
, 1999, “
Effect of Triggering on the Energy Absorption Capacity of Axially Compressed Aluminum Tubes
,”
Mater. Des.
0264-1275,
20
(
1
), pp.
31
40
.
16.
Abramowicz
,
W.
, and
Jones
,
N.
, 1986, “
Dynamic Progressive Buckling of Circular and Square Tubes
,”
Int. J. Impact Eng.
0734-743X,
4
(
4
), pp.
243
270
.
17.
Bodlani
,
S. B.
,
Chung Kim Yuen
,
S.
, and
Nurick
,
G. N.
, 2009, “
The Energy Absorption Characteristics of Square Mild Steel Tubes With Multiple Induced Circular Hole Discontinuities—Part II: Numerical Simulations
,”
ASME J. Appl. Mech.
0021-8936,
76
, p.
041013
.
18.
Otubushin
,
A.
, 1998, “
Detailed Validation of a Non-Linear Finite Element Code Using Dynamic Axial Crushing of a Square Tube
,”
Int. J. Impact Eng.
0734-743X,
21
(
5
), pp.
349
368
.
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