本文中利用無元素葛勒金法求解二維彈性動力問題，並以微分再生核近似法求得狀函數及其導函數，其中微分再生核近似法建構出的形狀函數及其導函數，在高階導數中具有連續性，因此使用此方法在應力方面所得之結果比有限元素法更可獲得較佳之精度及連續性。
本文的數值範例所得之結果與ABAQUS進行比較，並與一維震動棒之解析解比較，其成果令人滿意，再度驗證本文使用方法於二維彈性動態分析上之可行性。

In this paper we use the element free Galerkin method to solve the 2-D elastic-dynamical problems. The shape functions and it’s derivation are obtained by the differential reproduction kernel approximation(DRKA).The shape functions and its derivations conducted from the DRKA is high order continuous in the global, thus the stress acquired form present method is more continuous and accuracy than the finite element method.

In the numerical example we comparing the data analyzed in this article and by ABAQUS, also compared the result with analytic solution of a 1-D vibration of a rod. The result is satisfying and proves the feasibility of present method on 2-D elastic-dynamical analysis.

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