撓度指標法則用於解讀鋪面結構強度，其中以第一接收器撓度值 (MD)，面層曲率指標 (SCI) 與基層曲率指標 (BCI) 最為常用。本文除以動態力學分析為其建立理論根據外，更藉不同驗證了解各指標之適用性。研究結果顯示其對柔性鋪面整體結構強度評估雖具有相當之可信度， 但對於鋪面各層的實際狀況仍缺乏準確的評估。 就穩態撓度試驗而言， BCI 指標值對路基土壤之詮釋能力不佳； 衝擊式撓度試驗中，MD 指標值並無法正確地反應具瀝青處理底層道路之鋪面結構強度。傳統撓度指標法則雖可觀察道路加鋪前後之改善，但對於結構強度衰減主因以及相應之有效的維修方案仍有待進一步研究以加強。In the pavement deflection index method, a number of deflection indices are used to interpret the pavement structural capacity. Among them, the maximum deflection at the first sensor (MD), the surface curvature index (SCI), and the base curvature index (BCI) are commonly used. In this study, a theoretically sound base for the index method based on dynamic analysis is developed. The applicability of this method is verified through theoretical and experimental case studies. The results indicate that although this method can provide some qualitative information of the pavement structural capacity, the detailed degradation of the layer modulus (or strength) cannot be obtained by using these indices. For steady state testing, the BCI index is rarely correlated to the strength of the subgrade soils; for impulsive testing, the MD index works poorly in predicting the structural number of flexible pavements with bituminous treated base. Never-theless, these indices are useful in showing the overlay improvements. The main reason of pavement distress and the most efficient rehabilitation procedure suggested by the deflection index method need further study.