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Elastic flexural and torsional buckling behavior of pre-twisted bar under axial load

  • Chen, Chang Hong (School of Mechanics and Civil Engineering, Northwestern Polytechnical University) ;
  • Yao, Yao (School of Mechanics and Civil Engineering, Northwestern Polytechnical University) ;
  • Huang, Ying (School of Civil Engineering, Xi'an University of Architecture and Technology)
  • Received : 2012.05.10
  • Accepted : 2013.12.27
  • Published : 2014.01.25

Abstract

According to deformation features of pre-twisted bar, its elastic bending and torsion buckling equation is developed in the paper. The equation indicates that the bending buckling deformations in two main bending directions are coupled with each other, bending and twist buckling deformations are coupled with each other as well. However, for pre-twisted bar with dual-axis symmetry cross-section, bending buckling deformations are independent to the twist buckling deformation. The research indicates that the elastic torsion buckling load is not related to the pre-twisted angle, and equals to the torsion buckling load of the straight bar. Finite element analysis to pre-twisted bar with different pre-twisted angle is performed, the prediction shows that the assumption of a plane elastic bending buckling deformation curve proposed in previous literature (Shadnam and Abbasnia 2002) may not be accurate, and the curve deviates more from a plane with increasing of the pre-twisting angle. Finally, the parameters analysis is carried out to obtain the relationships between elastic bending buckling critical capacity, the effect of different pre-twisted angles and bending rigidity ratios are studied. The numerical results show that the existence of the pre-twisted angle leads to "resistance" effect of the stronger axis on buckling deformation, and enhances the elastic bending buckling critical capacity. It is noted that the "resistance" is getting stronger and the elastic buckling capacity is higher as the cross section bending rigidity ratio increases.

References

  1. ANSYS Inc. (2007), ANSYS APDL Programmer's Guide Release 11.0, 3th Edition, America.
  2. Banerjee. J.R. (2004), "Development of an exact dynamic stiffness matrix for free vibration analysis of a twisted Timoshenko beam", J. Sound Vib., 270(9), 379-401. https://doi.org/10.1016/S0022-460X(03)00633-3
  3. Barnett, J.F. (1999), "A bridge for the bridges", Conference Proceedings for Bridges, American.
  4. Hsu, M.H. (2009), "Vibration analysis of pre-twisted beams using the spline collocation method", J. Marine Sci. Tech., 17(2), 106-115.
  5. Leung, A.Y.T. (2010a), "Natural vibration of pre-twisted shear deformable beam systems subject to multiple kinds of initial stresses", J. Sound .Vib., 329(10), 1901-1923. https://doi.org/10.1016/j.jsv.2009.12.002
  6. Leung, A.Y.T. (2010b), "Vibration of thin pre-twisted helical beams", Int. J. Solid. Struct., 47(9), 1177-1195. https://doi.org/10.1016/j.ijsolstr.2010.01.005
  7. Leung, A.Y.T. (2010c), "Dynamics and buckling of thin pre-twisted beams under axial load and torque", Int. J. Struct. Stab. Dyn., 32(10), 957-981.
  8. Petrov, E. and Geradin, M. (1998), "Finite element theory for curved and twisted beams based on exact solutions for three dimensional solids. Part 1: beam concept and geometrically exact nonlinear fomulation, Part 2: anisotropic and advanced beam models", Comput. Meth. Appl. Mech. Eng., 165(6), 43-127. https://doi.org/10.1016/S0045-7825(98)00061-9
  9. Yu, A.M., Yang, J.W., Nie, G.H. and Yang, X.G. (2011), "An improved model for naturally curved and twisted composite beams with closed thin-walled sections", Compos. Struct., 93( 9), 2322-2329. https://doi.org/10.1016/j.compstruct.2011.03.020
  10. Yu, W.B. and Liao, L. (2005), "Dewey H Hodges, et al. Theory of initially twisted, composite thin-walled beams", Thin Wall. Struct., 43(5), 1296-1311. https://doi.org/10.1016/j.tws.2005.02.001
  11. Sequin, C.H. (2000), "To build a twisted bridge", Conference Proceedings for Bridges, American.
  12. Shadnam, M.R. and Abbasnia, R. (2002), "Stability of pre-twisted beams in crosses bracings", Appl. Mech. Tech. Phy., 43(2), 328-335. https://doi.org/10.1023/A:1014726314758
  13. Yu, A.M., Yang, R.Q. and Hao, Y. (2009), "Theory and application of naturally curved and twisted beams with closed thin-walled cross sections", J. Mech. Eng., 55(12), 733-741.
  14. Zelenina, A.A. and Zubov, L.M. (2006), "Saint Venant problem for a naturally twisted rod in nonlinear moment elasticity theory", Doklady Phy., 51(3), 136-139. https://doi.org/10.1134/S1028335806030104
  15. Zupan, D. and Saje, M. (2004), "On "A proposed standard set of problems to test finite element accuracy": the twisted beam", Finite Elem. Anal. Des., 40(5),1445-1451. https://doi.org/10.1016/j.finel.2003.10.001

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