落錘式撓度儀(Falling Weight Deflectometer, FWD)廣泛應用於鋪面檢測中，國內對於FWD數據並沒有充分分析，致使FWD作為後續評估受限。本研究深入探討FWD數據，分別對中工處三年之數據及岡山段現地測得之數據利用正規撓度值(Normalized Deflection)、衝擊勁度模數(Impulse Stiffness Modulus, ISM)、路基回彈模數Mr值、撓度面積Area及撓度面積參數Ar’等方法進行分析，並反算回彈模數，評估鋪面結構能力。正規化D0撓度值及衝擊勁度模數ISM值能表示整體鋪面之狀態，但容易受鋪面溫度及面層之厚度影響；路基回彈模數Mr值可判斷路段之路基差異，但與反算程式結果比較後發現路基回彈模數Mr值會有更高的數值。Area使用較多之撓度值來計算，作為鋪面強度指標較好，但當遇上撓度曲線整體下降或上升時會有誤判的結果，軟弱鋪面與良好鋪面可能會有相近之Area值。面積參數Ar’值為各方法中較可行之指標，所使用之參數較多，能反映鋪面狀況；而反算結果顯示面積Area值及面積參數Ar’值相對於碎石級配層及路基層較容易受鋪面面層影響。

Although Falling Weight Deflectometer (FWD) is widely used in pavement performance test, FWD data has not been fully analyzed, resulting in limited use of FWD as a follow-up assessment. This study investigates the three years FWD data collected by Central Area National Freeway Bureau, and the Gang Shan district in situ testing FWD data, respectively using normalized deflection, impulse stiffness modulus (ISM), AASHTO Mr equation, Area method and Area parameter (Ar’) such methods to analyze, and with backcalculated modulus, evaluating the pavement structural capacity. Normalized D0 deflection and impulse stiffness modulus ISM can indicate the status of the pavement, however, they are susceptible to the temperature and thickness of pavement surface layer; AASHTO Mr equation can determine the variety of the subgrade among the testing sections, but comparison with the backcalculated results shows that AASHTO Mr equation will have a higher subgrade resilient modulus. As Area method involves more deflections to calculate, it is a better pavement strength index, however, it may have a misjudging result when the overall deflection bowl drops or rises, weak pavement and strong pavement may have similar Area value. Area parameter Ar’ is the most feasible method among all the indicators, it involves more deflections and can assess pavement situation; backcalculation result shows that Area method and Area parameter Ar’ are more susceptible to be affected by pavement surface rather than crushed stone subbase and subgrade.

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