Free vibration analysis of a thin-walled box girder based on the differential transformation method
TAN Minyao1，HE Yang2
1. College of Automation Chengdu University of Information Technology, Chengdu 610225, China;
2. Chengdu Municipal Engineering Design and Research Institute Co., Ltd., Chengdu 610023, China
Abstract：In order to improve the accuracy of the higher order natural frequency solution of the free vibration of thin-walled box girder, a general mathematical method is proposed to analyze the free vibration characteristics of thin-walled box girder, including the influence of cross-section deformation. Based on the generalized coordinate principle, the governing equations of motion and the corresponding boundary conditions and continuous conditions are derived by the variational principle of virtual work, and then solved by the differential transformation method. The model takes into account the warping and distortion deformation of the box girder loading surface, which has universality and effectiveness. In the example analysis, the natural frequencies were calculated and the mode shape diagrams were drawn. Compared with the known literature, it can be seen that: The theoretical method of solving natural frequency in this paper is in good agreement with the results of known literatures. This methods improves the accuracy of natural frequency of free vibration of thin-walled box girder by considering distortion effect. It can be used to calculate the natural frequency of box girder under different boundary conditions. Transverse deformation and distortion deformation play an important role in the mode diagrams.
Key words: bending; warping; torsion; distortion; Differential transform method
谭敏尧1，何洋2. 基于微分变换法的薄壁箱梁的自由振动分析[J]. 振动与冲击, 2022, 41(18): 121-126.
TAN Minyao1，HE Yang2. Free vibration analysis of a thin-walled box girder based on the differential transformation method. JOURNAL OF VIBRATION AND SHOCK, 2022, 41(18): 121-126.
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