Analysis of transverse vibration of axially moving soft sandwich beam

作者：Lü Hai Wei; Li Ying Hui; Li Liang; Xu Jiang

来源：Journal of Vibration and Shock, 2014, 33(2): 41-46+51.

• Axially moving
• Compressible core
• Continuity conditions
• Independent variables
• Sandwich beams
• Second-order polynomial
• Transverse displacements
• Transverse vibrations

In consideration of the shortcoming of traditional sandwich beam theory that the sandwich beam is assumed to be incompressible in thickness direction, a new sandwich beam theory was proposed by introducing independent variables in terms of the displacements of top face sheet, middle plane of soft core and bottom face sheet. The displacement of soft core was approximated by a second order polynomial in thickness direction. Using continuity conditions along the face sheets and soft core, the transverse displacement of the soft core was solved. The normal strain and shearing strain of the soft core in thickness direction were also obtained. Based on the Hamilton principle, the governing equation of the system was established. The Galerkin truncation method was used to solve the governing equation. It is found that: the first mode of soft sandwich beam displays that the face sheets and soft core move together in transverse direction and there is no relative deformation between the face sheets and soft core, this case is consistent with the traditional sandwich beam theory; the second mode of soft sandwich beam shows that the two face sheets move in opposite direction and the middle plane of soft core does not move, so the soft core is in the state of tension or in compression; the third mode of soft sandwich beam displays that the two face sheet move in the same direction and the soft core moves in opposite direction, so the upper part and lower part of soft core are in different deformation state (tension or compression). By inspecting modal shapes, mode functions, responses of free vibration, the effect of axially moving velocity on frequencies and so on, it is concluded that the incompressible model of sandwich beam is only a special form of the soft sandwich beam model proposed in the paper.

• 出版日期2014
• 单位西南交通大学