Free axisymmetric vibrations of composite annular sandwich plates with thick isotropic core and orthotropic facings have been studied using Reddy's higher-order shear deformation theory. Core is assumed to be of uniform thickness while the face sheets are treated as membranes. Equations of motion and natural boundary conditions are developed using Hamilton's principle. Chebyshev collocation technique has been applied to get the frequency equations for clamped-clamped, clamped-simply supported and clamped-free edge conditions. Obtained equations are solved numerically for the lowest three roots and reported as the frequency parameters for the first three modes of vibration. Results obtained from the proposed approach are validated by comparing them numerically and graphically with their counterparts available in the literature. Detailed numerical results are given to analyze the effects of core thickness, thickness of faces and radii ratios on the frequency parameter. It is also shown that the published analysis based on first-order theory is not suitable for estimation of natural frequency of annular sandwich plate with thick core. Three dimensional mode shapes have been plotted for a specified plate for all the three boundary conditions.

利用Reddy的高阶剪切变形理论研究了厚各向同性芯和正交异性复合材料环形复合夹层板的自由轴对称振动。假定芯材厚度均匀，而将面板视为薄膜。运动方程和自然边界条件是使用汉密尔顿原理开发的。Chebyshev搭配技术已被应用来获得夹紧，夹紧，简单支撑和夹紧自由边缘条件的频率方程。将获得的方程式数值求解为最低的三个根，并报告为前三个振动模式的频率参数。通过从数字和图形上将它们与文献中可用的对应值进行比较，可以验证从所提出的方法获得的结果。给出了详细的数值结果，以分析铁心厚度，端面厚度和半径比对频率参数的影响。研究还表明，基于一阶理论的已发表分析不适合估算厚壁环形夹层板的固有频率。对于所有三个边界条件，已为指定板绘制了三维模式形状。