The Response of “Large” Square Tubes (Width/Thickness Ratio > 45) to Opposite Lateral Blast Loads Followed by Dynamic Axial Load
Experiments and Finite Element analyses are carried out to investigate the response of a square tube with width/thickness ratio (C / H) > 45 to two opposite lateral blast loads followed by dynamic axial load. The localised blast loads on opposite sides of 76 × 76 × 1.6 mm square tubes at mid-length create imperfections (triggers) that change the geometry and the material properties of the tube in the mid-section. The effects of the imperfections on the energy absorption characteristics of the tubular structure are investigated by means of the dynamic axial load. Similar studies have been carried out for tubes with C / H ratio of 33 [1–3]. In contrast to the tubes with C / H ratio of 33 where the lobe formation are regular in shape and size, the tubes with C / H ratio > 45 exhibit irregular lobe formation.
The Finite Element package ABAQUS/Explicit v6.5-6 is used to construct a 1/2 symmetry model using shell and continuum elements to simulate the tube response to the two loading conditions. The hydro-dynamic code AUTODYN is used to characterise the localised blast pressure spatial history. The Finite element simulations show satisfactory correlation with experiments for both crushed shapes.
Key wordscrashworthiness energy absorbers tube crushing triggers imperfections
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- 1.Chung Kim Yuen, S. and Nurick, G.N., Modelling of axial loading of square tubes with blastinduced imperfections, in Proceedings of 9th International Symposium on Plasticity and Impact Mechanics, IMPLAST 2007, Bochum, Germany, pp. 553–560, 2007.Google Scholar
- 2.Chung Kim Yuen, S. and Nurick, G.N., The crushing charateristics of square tubes with blastinduced imperfections — Part I: Experiments, J. Appl. Mech., 2008 (in review).Google Scholar
- 3.Chung Kim Yuen, S. and Nurick, G.N., The crushing charateristics of square tubes with blastinduced imperfections — Part II: Numerical simulations, J. Appl. Mech., 2008 (in review).Google Scholar
- 10.Thornton, P.H. and Magee, C.L., The interplay of geometric and materials variables in energy absorption, Trans. ASME, J. Eng. Matl. Tech. 99(2), 114–120, 1977.Google Scholar
- 12.Marais, S.T., Tait, R.B., Cloete, T.J. and Nurick, G.N., Material testing at high strain rate using the split Hopkinson pressure bar, Lat. Am. J. Solids Structures 1(3), 319–338, 2004.Google Scholar
- 13.Masui, T., Nunokawa, T. and Hiramatsu, T., Shape correction of hot rolled steel using an on line leveller, J. Japan Soc. Technol. Plasticity 28(312), 81–87, 1987.Google Scholar
- 14.Chung Kim Yuen, S. and Nurick, G.N., Deformation and tearing of uniformly blast-loaded quadrangular stiffened plates, in Proceedings International Conference on Structural Engineering, Mech. and Comp. (SEMC), Cape Town, South Africa, pp. 1029–1036, 2001.Google Scholar
- 15.Chung Kim Yuen, S. and Nurick, G.N., Modelling the deformation and tearing of thin and thick plates subjected to localised blast loads, in Proceedings 8th International Symposium on Plasticity and Impact Mechanics, IMPLAST 2003, New Delhi, India, pp. 729–739, 2003.Google Scholar
- 19.Nurick, G.N. and Radford, A.M., Deformation and tearing of clamped circular plates subjected to localised central blast loads, in Recent Developments in Computational and Applied Mechanics: A Volume in Honour of John B. Martin, International Centre for Numerical Methods in Engineering (CIMNE), Barcelona, Spain, pp. 276–301, 1997.Google Scholar
- 20.Chung Kim Yuen, S. and Nurick, G.N., The significance of the thickness of a plate when subjected to localised blast load, in Proceedings 16th International Symposium on Military Aspects of Blast and Shock, (MABS 16), Oxford, UK, pp. 491–499, 2000.Google Scholar