复合材料层合圆柱壳的动力响应与层间应力

采用分层壳理论和厚度方向的二次插值函数推导出正交铺设层合圆柱壳的动力响应方程,并得出简支层合圆柱壳自由振动问题的解.对于给定算例,计算出的自振频率与三维分析的结果吻合良好,说明所推导的二维解具有足够精度.计算了前四阶模态对应的壳中应力.计算结果说明,对于高阶模态,层间应力相对于面内应力的比值远高于低阶模态的对应比值,高的层间正应力是高阶模态导致脱层破坏的主要原因.

Vibration and transverse stresses of laminated cylindrical shells

The governing equations for dynamic response of laminated cylindrical shells with orthotropic layers are derived by use of layer wise shell theory, with quadratic interpolation function adopted in shell thickness direction. The solutions of the equations are presented for free vibration of the shells with simply supported boundaries. The vibration frequencies given by the solutions are in good agreement with the results of three dimensional analysis. Stresses in the shells are calculated for the first four modes. The results show that the ration of transverse normal stress to inplane stress for the third and fourth modes are more higher than that for the first and second modes. High transverse normal stress is a main cause for delamination that results from high frequency dynamic response of laminated shells.