Abstract:The main bodies can usually be simplified as beams in the study of low-frequency vibrations of ships, submarines, and other engineering structures. While the couplings between bending and longitudinal vibrations will arise because of the non-uniform mass distribution in the cross-section. Analytical expression of cut-off frequency for the bending-longitudinal coupled eccentric Timoshenko beam was derived. Influences of eccentricity on the longitudinal waves, propagating bending waves, and decaying bending waves were discussed. Variations of longitudinal/bending displacement ratio with frequency and eccentricity under three sets of wavenumbers were studied. Analysis results show that eccentricity reduces the cut-off frequency of beam. The greater the eccentricity, the more obvious the reduction. The decaying bending wave transforms into propagating one at the cut-off frequency. Eccentricity induces the transition of longitudinal wave from non-dispersive one to dispersive one. If the eccentricity or frequency increases, or both, the bending-longitudinal coupling will be further strengthened.
王剑1,2,袁秀峰2,胡永彪1. 质量偏心Timoshenko梁的振动波特性研究[J]. 振动与冲击, 2022, 41(1): 265-270.
WANG Jian1,2, YUAN Xiufeng2, HU Yongbiao1. Vibration wave characteristics of Timoshenko beam with eccentric mass. JOURNAL OF VIBRATION AND SHOCK, 2022, 41(1): 265-270.
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