本文旨在研究孔洞對裂紋漸近場高階參數之影響，文中首先推演均質正交異向性材料在裂縫尖端的應力與位移含高階參數之漸近場表達式，其後介紹最小二乘法原理與配合應用ABAQUS軟體進行高階項係數之計算，數值範例中探討了均質正交異向性材料裂縫體，受拉應力或剪應力作用下孔洞對高階項係數之影響，高階項係數數值計算之收斂性和精確度也做了討論與比較。

The aim of this research is to study the influence of a hole on high-order parameters of near-tip fields of a crack .First of all, the expression of the asymptotic stress and displacement fields including the high-order parameters of a crack tip are introduced for an orthotropic material. After that, the Least-squares method is introduced along with the use of ABAQUS software to calculate high-order parameters.The influence of holes on high-order parameters are studied by several numerical examples where the cracked orthotropic material is subjected to tensile stress or shear stress.The convergence and accuracy of the numerical computations of high-order parameters are also discussed and compared.

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