A spectral finite element model for vibration analysis of a beam based on general higher-order theory

Article type: Research Article

Authors: Sujuan, Jiao | Jun, Li | Hongxing, Hua | Rongying, Shen

Affiliations: Vibration, Shock & Noise Institute, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China

Abstract: The spectral element matrix is derived for a straight and uniform beam element having an arbitrary cross-section. The general higher-order beam theory is used, which accurately accounts for the transverse shear deformation out of the cross-sectional plane and antielastic-type deformation within the cross-sectional plane. Two coupled equations of motion are derived by use of Hamilton's principle along with the full three-dimensional constitutive relations. The theoretical expressions of the spectral element matrix are formulated from the exact solutions of the coupled governing equations. The developed spectral element matrix is directly applied to calculate the exact natural frequencies and mode shapes of the illustrative examples. Numerical results of the thick isotropic beams with rectangular and elliptical cross-sections are presented for a wide variety of cross-section aspect ratios.

Keywords: Beam, higher-order, shear deformation, dynamic analysis, spectral element matrix

Journal: Shock and Vibration, vol. 15, no. 2, pp. 179-192, 2008