複合疊層板的應力譜試驗是疲勞設計中很重要的試驗，藉由模擬實際應力譜的行為，複合疊層板實際使用的壽命，方能更準確地預估。然而在經濟的考量下，要完成整個應力譜試驗，往往花費許多時間與成本。建立一套合理的方法以移除對材料不受影響的負載，而簡化應力譜，才能讓材料受疲勞試驗的時間縮短，達到試驗加速的效果。

本文針對加速試驗簡化應力譜疲勞行為做研究，利用前人勁度遞減模式，去預測複合疊層板的殘餘勁度、破壞勁度以及疲勞壽命，藉由比較簡化後的應力譜實驗值，以驗證理論模式預測疲勞行為的可行性。理論預測的結果顯示與實驗的結果相當吻合，證明了先前疲勞損傷的理論模式於不同負荷順序應力譜仍然有效。

It’s important for performing spectrum fatigue test under the stage of design and test of composite laminates. By simulating actual spectrum loading, fatigue behaviors of composite laminates can be predicted in a more precise way with closeness to the actual usage compared to constant amplitude fatigue loading. Considering economics, however, it must spend a lot of time and cost if one should accomplish the actual fatigue test in service. A method to simplify the fatigue loading by truncating harmless fatigue cycles in the spectrum loading and to accelerate the fatigue testing, therefore, should be available.
With the simplified method proposed in a previous study on fatigue spectrum loading, this study mainly aims to predict the fatigue behavior of composite laminates under the accelerated fatigue spectrum loading. Based on the pre-established stiffness degradation model, residual stiffness, failure stiffness and fatigue life for composite laminates can be predicted with baseline test data. Comparing experimental test results of condensed spectrum loading, we conclude that the model for predicting fatigue behavior is feasible. It also indicates that the stiffness degradation model is valid for different loading sequence of fatigue.

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