本文採用移動最小二乘法(Moving Least Square Method)來分析圓柱薄殼挫屈問題。首先基於一階剪應變形之假設導出圓柱殼結構的合應力、應變與位移的關係，進而建立圓柱殼的挫屈的控制方程式，再利用移動最小二乘法進行離散化建立數值運算程序以分析在各種荷重與邊界條件下圓柱殼之挫屈荷重與挫屈模態。
本文探討圓柱薄殼受側向圍壓、軸向壓力與扭力作用之挫屈行為。邊界條件考慮了兩邊簡支承端、兩邊固定端與一邊簡支承端一邊固定端等情況。在計算例中針對不同基底函數階數、板尺寸、厚度等因素探討對挫屈荷重與模態的影響。並用分析數據收斂結果與解析解進行比較驗證了本文方法之準確性。

In this paper, we use the Moving Least Square Method to analysis the buckling of cylindrical shell. Base the assumption of first order shear deformation, we derived the relationship between the stress results, strains and displacements of the cylindrical shell, and then establish the governing equations of buckling of the cylindrical shell. Using the Moving Least Square Method we establish a numerical procedure to analysis the buckling load and mode shape of a cylindrical shell under various loadings and boundary conditions.
In this paper, we discuss the buckling behavior of a thin cylindrical shell under lateral confining pressure, axial pressure and torque. The boundary conditions of both sides simply supported, both sides of fixed end and one side simply supported one side fixed are considered. In the examples we the accuracy of numeral results under different order of the basis function, size and thickness of plate, the results were compared with the analytical solution to validate the accuracy of this method.

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