本研究提出一種新穎的方法，用於分析非對稱C型複合材料梁，無論是在對稱或非對稱的疊層順序情況下。該方法利用經典層合理論（Classical Lamination Theory）來修改，結合重心和剪切中心概念，推導出非對稱C型複合材料梁之截面性質的明確表達式，包括軸向（Axial）、彎曲（Bending）、扭轉（Torsional）和翹曲剛性（Warping Stiffness）。過程中進行一連串的假設與優化，其中最重要的假設莫過於考慮在結構梁中觀察到獨特的變形行為，而這些假設都建立在彈性變形之下。為了驗證該解析解的準確性，將此結果與三維有限元分析進行比較。在驗證軸向和彎曲剛性之後，搭配驗證軸向應力確認建模正確後，再驗證扭轉和翹曲剛性。這項研究還將參數進行調整，包括各種斷面尺寸、梁的長度和疊層角度，探討與驗證在各種變化之下，等效剛性的影響與準確性。另外，在極端疊層順序情況下，探討此方法與不考慮結構斷面效應之間的比較。同時，比較優化前與優化後的差異。這個新穎的方法能夠加速對非對稱C型複合材料梁的等效剛性評估，與初步設計階段的實際應用具有重要的相關性。

A novel methodology for the analysis of asymmetric C-shaped laminated composite beams is proposed in this work. Moreover, the proposed approach leverages an adapted Classical Lamination Theory (CLT) with centroid and shear center concepts to derive explicit expressions for the evaluation of crucial sectional properties, including axial, bending, torsional, and warping stiffness. The analytical formulations account for the distinctive deformation characteristics observed in structural beams. To validate the accuracy of the proposed analytical expressions, three-dimensional finite element analyses are performed for comparisons between analytical and numerical results. The solutions for axial and bending stiffness are examined, along with torsional and warping stiffness. Parametric studies are conducted, including various cross-sectional dimensions, the length of the beam, and the stacking sequences of the composite laminates. This study investigates the comparisons between the proposed methodology and the methodology that does not consider the effect of the structural cross-section. Additionally, a comprehensive analysis of the methodology is conducted for both symmetric and asymmetric stacking sequences in this research. This novel approach expedites the assessment of the behavior of laminated composite beams and holds significant relevance for practical applications in the preliminary design phase.

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