由於T型複材疊層結構優異的高強度、高剛度與重量比表現，使其廣泛應用在飛機的複合材料結構形式。但由於T型複材疊層結構的關鍵應力區常存在複雜的應力分布，傳統的有限元素方法也缺乏精確預測其漸進式損傷機制，因此過去幾十年來數值方法在此類問題的應用上受到越來越多關注。本研究使用ABAQUS建立T型複材疊層結構的有限元素模型，並使用美國國家航太總署(NASA) Langley Research Center 針對預測複合材料損傷開發的LaRC04破壞準則。其中複材疊層結構層內使用連續損傷力學模型，其藉由元素的局部勁度遞減來描述層內損傷，並比較不同的連續損傷力學模型對分析結果的影響。另一方面，層間的脫層損傷機制則使用內聚力元素來模擬。本研究對T型複材疊層結構做了一個完整漸進式損傷分析步驟，提出實務上減少積木式工程驗證法的成本的方式。結果表明，目前單獨使用內聚力元素的模擬方法不足以分析漸進式損傷機制。同時使用連續損傷力學模型與內聚力元素能更完整模擬出疊層與填充區域等結構之間的層內與層間的損傷。研究成果也顯示不同的連續損傷力學模型在T型複材疊層結構的分析結果的適應性，並驗證網格數量對連續損傷力學模型的影響。本研究對於瞭解複合材料結構的損傷行為和設計應用，提供具有重要的參考價值和實際意義。

T-joint composite structures are widely used in modern aircraft construction due to their excellent strength-weight ratio. However, the complex stress distribution in T-joints and the limitations of traditional finite element methods in accurately predicting the progressive damage mechanisms have led to increased interest in numerical methods for addressing these challenges. In this study, a finite element model for T-joint composite structures were developed in ABAQUS. The damage criterion LaRC04, developed by NASA Langley Research Center, was utilized to predict the damage occur in composite materials. Within the composite laminate layers, a continuum damage model (CDM) was employed to describe intra-ply damage by considering local stiffness degradation. This study also compared different continuum damage models to assess their impact on the analysis results. For inter-ply delamination, cohesive elements were used for simulation. A comprehensive modeling and progressive damage analysis procedure was conducted to provide a cost-effective approach for T-joint composite laminates, aiming to reduce the reliance on block-by-block engineering verification methods. The results showed that the combined use of continuum damage models and cohesive elements effectively simulated both intra-ply and inter-ply damage in the laminates and bonding regions. This study also demonstrated the adaptability of different continuum damage models and verified the influence of mesh density on T-joint model. Overall, this research contributes valuable insights for understanding the damage behavior and design applications of composite material structures.

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