复合材料梁结构应力波传播特性研究

摘要

The wave reflection and transmission in composite beams containing a semi-infinite delamination were studied analytically based on the Timoshenko beam theory.Two extreme cases of delaminated surface conditions,non-contact(open)and full contact(closed)delaminations,were considered respectively for a unidirectional composite beam. The analytical solution of reflection and transmission matrices for a semi-infinite delamination was derived.Then the power reflection and transmission coefficients were obtained,which depend on both the wave frequency and the location of the delamination.The numerical results show the conservation of power transport.The power distribution was also investigated to describe the mode conversion between two flexural modes and one extensional mode.A finite element simulation was used to verify the validity of the analytical results.%基于铁木辛柯梁理论，研究含半无限大分层复合材料梁结构中波的反射与透射。考虑表面无接触压力（张开分层）及表面完全接触（闭合分层）两种极端分层条件，对单向复合材料梁建模导出反射与透射矩阵，计算能量反射与透射系数。数值结果表明，能量反射与透射系数同随波频率及分层位置变化，能量传输遵循守恒定律。研究各模态能量分配，描述前两阶弯曲波及第一阶膨胀波间模态转换关系；通过有限元仿真验证该理论分析的正确性。