On quasi-static crushing of thin-walled steel structures in cold temperature: Experimental and numerical studies

• Published in: International journal of impact engineering 2011, Vol.38 (1), p.13-28
• Main Authors: Paik, Jeom Kee, Kim, Bong Ju, Park, Dae Kyeom, Jang, Bong Seok
• Format: Article
• Language: English
• Subjects: Chambers; Cold temperatures; Computer simulation; Crushing; Exact sciences and technology; Experiment; Fracture behaviour; Fracture mechanics; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Inelasticity (thermoplasticity, viscoplasticity...); Liquid nitrogen; Physics; Quasi-static crushing; Solid mechanics; Square tube; Strain; Structural and continuum mechanics; Thin walled; Tubes
• ISSN: 0734-743X; 1879-3509
• DOI: 10.1016/j.ijimpeng.2010.08.004

The aim of the study reported herein was to investigate the effects of low temperatures on the crushing characteristics of steel plated structures. The motivation of this study is for the analysis of ship collisions in Arctic waters. A series of tensile coupon tests were performed to examine their material behaviour at low temperatures, and then quasi-static axial crushing tests were carried out on thin-walled square tubes. The test tubes were made of ASTM A500-type carbon steel, and both the tensile coupon tests of the material and the crushing tests of the tubes were performed in a liquid nitrogen cooled chamber. To reflect the conditions of the Arctic environment more realistically, the tensile coupon tests of the material were also carried out in a dry-ice cooled chamber. LS-DYNA nonlinear finite element method simulations applying a practical approach of modelling techniques were performed to investigate the structural crashworthiness of the thin-walled steel tubes numerically. The tests in the liquid nitrogen cooled chamber showed that the fracture strain of the material was not affected (reduced) by temperatures as low as −80 °C, although fracture strain was significantly reduced below −100 °C. The fracture strain results obtained in the dry-ice cooled chamber, however, show this strain to be affected (reduced) by low temperatures even between 0 °C and −80 °C, which is equivalent to the Arctic environment. It was also observed that fracture occurs in thin-walled tubes under crushing loads at low temperatures. The LS-DYNA computations also detected the fracture behaviour of test tubes in cold temperatures in a relevant way.