Advanced Steel Construction

Vol. 5, No. 2, pp. 151-163 (2009)


NUMERICAL ANALYSES OF COLD-FORMED THIN-WALLED SECTIONS WITH CONSIDERATION OF IMPERFECTIONS DUE TO THE PRODUCTION PROCESS

 

Albrecht Gehring 1 and Helmut Saal 2,*

1 Research assistant, Versuchsanstalt für Stahl, Holz und Steine, Universität Karlsruhe (TH), Germany

2 Professor, Versuchsanstalt für Stahl, Holz und Steine, Universität Karlsruhe (TH), Germany

*(Corresponding author: E-mail: >This email address is being protected from spambots. You need JavaScript enabled to view it.)

 

DOI:10.18057/IJASC.2009.5.2.5

 

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ABSTRACT

  The load bearing capacity of cold-formed thin-walled sections strongly depends on deviations from the nominal dimensions and the material properties. The former reduce the load bearing capacity. The latter enhance the load bearing capacity, because of work hardening during the manufacturing process. It is difficult to realistically account for both effects in a finite-element analysis of the load bearing capacity of thin-walled sections. Today, cost intensive testing is necessary, if a maximum utilization of the load bearing capacity is desired. The properties of a product can be determined during the product development process with a new simulation strategy, which covers the production process as well as the state of serviceability of a product. The roll forming process is simulated first followed by a non-linear ultimate limit state analysis. The combination of both analysis steps gives the possibility to determine the load bearing capacity realistically as deviations from the nominal value of dimensions and material properties are included in the analysis. The new analysis strategy is demonstrated for a U-section with respect to different aspects concerning work hardening and the load bearing capacity of a C-section. It is shown, that the new strategy leads to a realistic estimation of the load bearing capacity of thin gauged sections.

 

KEYWORDS

Numerical analyses, cold-formed sections, imperfections, work hardening, ultimate limit state.


REFERENCES

[1]       Halmos, G.T. (Edit.), “Roll Forming Handbook”, CRC Press Taylor & Francis Group, Boca Raton, 2006

[2]       Bogojawlenskij, K.N., Neubauer, A. and Ris, V.W., “Technologie der Fertigung von Leichtbauprofilen“, VEB Deutscher Verlag für Grundstoffindustrie, Leipzig, 1979.

[3]       ABAQUS Documentation – Version 6.6.1, Copyright 2006, ABAQUS, Inc.

[4]       ABAQUS (Explicit & Standard); Version 6.6.1, Copyright 2006, ABAQUS, Inc.

[5]       http://www.rz.uni-karlsruhe.de/ssc/hpxc

[6]       Gehring, A. and Saal, H., “Sensitivity Analysis of Technological and Material Parameters in Roll Forming”, Proceedings of the 9th International Conference on Numerical Methods in Industrial Forming Processes, Porto, 2007, pp. 781.

[7]       Khan, A.S. and Huang, S., “Continuum Theory of Plasticity”, John Wiley & Sons, Inc., New York, 1995.

[8]       Lange, K. (Edit.), “Umformtechnik – Handbuch für Industrie und Wissenschaft, Band 1: Grundlagen“, Berlin: Springer Verlag, 1984.

[9]       Engl, B. and Stich, G., “Neue Stahlsorten für die Kaltformung“, Tagungsband 722, Studiengesellschaft für Stahlanwendung e.V., 1998.

[10]     EN 1993-1-3:2006, Eurocode 3 - Design of Steel Structures - Part 1-3: General Rules - Supplementary Rules for Cold-formed Members and Sheeting.

[11]     Yu, W.-W., “Cold-formed Steel Design”, 3rd Edition, John Wiley & Sons, New York, 2001.

[12]     EN 1993-1-5:2006, Eurocode 3 - Design of Steel Structures - Part 1-5: General Rules - Supplementary Rules for Cold-formed Members and Sheeting, Annex C.

[13]     Schafer, B.W. and Peköz, T., “Computational Modeling of Cold-formed Steel: Characterizing Geometric Imperfections and Residual Stresses”, Journal of Constructional Steel Research, 1998, Vol. 47, pp. 193 – 210.

[14]     Garnder, L. and Nethercot, D.A., “Numerical Modeling of Stainless Steel Structural Components – A Consistent Approach”, Journal of Structural Engineering, 2004, Vol. 130, pp. 1586 – 1601.

[15]     Lecce, M. and Rasmussen, K., “Distortional Buckling of Cold-formed Stainless Steel Sections: Experimental Investigation”, Journal of Structural Engineering, 2006, Vol. 132, pp. 497 – 504.

[16]     Gehring, A., Kathage, K. and Saal, H., “A New Strategy for Finite-element Analysis of the Load Bearing Capacity of Cold-formed Sections”, Proceedings of the 3rd International Conference on Structural Engineering, Mechanics and Computation, Capetown, 2007, pp. 377.

[17]     EN 10326:2004, Continuously Hot-dip Coated Strip and Sheet of Structural Steels - Technical Delivery Conditions.

[18]     Gehring, A. and Saal, H., “Yield Strength Distribution in Thin-walled Sections Due to Roll Forming – A Finite-Element Analysis”, Proceedings of the 6th International Conference on Steel and Aluminium Structures, Oxford, 2007, pp. 864.

[19]     Box, G.E.P., Hunter, W.G. and Hunter, J.S., “Statistics for Experimenters”, 2nd Edition, New York: John Wiley & Sons, 2005.

[20]     Statistica 7.1, Copyright 1986 - 2005, StatSoft, Inc.