Inelastic Static and Dynamic Stability Analyses of a Column Subjected to a Nonconservative Force

Abstract

This study performs the inelastic static and dynamic stability analyses of a column subjected to a nonconservative force using the finite element method. Based on the tangent modulus theory, the nonlinear compressive stress–strain and tangent modulus–stress relationships of an inelastic column are derived from the column strength curves given in two design codes. The extended Hamilton principle is employed to obtain the mass, elastic stiffness, and geometric stiffness matrices. Evaluation procedures for the critical values of buckling and flutter of the nonconservative systems are briefly introduced. In numerical examples, the influence of various parameters on the inelastic static and dynamic stability of the nonconservative systems is addressed as follows: (1) the effect of the nonconservativeness parameter on the critical buckling and flutter loads of the column for the inelastic stability analysis from the characteristic curves, (2) the variation of the effective length factor (K-factor) for inelastic columns with respect to the nonconservativeness parameter.

Keywords:

• Dynamic stability
• Finite element method
• Inelastic column
• Nonconservative force

ACKNOWLEDGMENTS

This research was supported by WCU (World Class University) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (R32-2008-000-20042-0). This work is a part of a research project supported by Korea Ministry of Land, Transportation Maritime Affairs (MLTM) through Core Research Project 1 of Super Long Span Bridge R&D Center. This work was also supported by the Korea Research Foundation Grant funded by the Korean government (MOEHRD, Basic Research Promotion Fund, grant KRF-2008-313-D01043). The authors wish to express their gratitude for the financial support.

Notes

^#Communicated by M. Amabili.