本研究以ABAQUS這套有限元素法建構與一般擬動態模擬法不同的動態分析法來尋求反算結果的修正方式。捨棄以往擬動態的作用力歷時分析法改採動態的模擬落錘敲擊法以逼近現實FWD施作方式，以避免忽略衝擊載重本身與鋪面的動態互制行為。本研究中發現FWD衝擊模型可在LTPP 編號29-54831-1實驗路段量測的合理數據範圍內找到一條與現地FWD量測變位值平均誤差在5%左右的模擬變位；在同樣情況下以擬動態模擬方式並無法於合理範圍中找到精確的模擬變位，誤差量高達80%以上。本研究最後並以MODULUS與動態模型比較方式找出修正靜力反算的修正式，可將原先MODULUS反算平均誤差面層66%、路基15.8%分別修正到9.34%與5.07%。

In this study, backcalculation correcting procedure is found by using F.E. program to simulate mass falling from a specific distance which is different from FWD time-history model used before. We use falling model instead of time-history model in order to take mass of block and pavement into concern. FWD Falling model is verified by using LTPP 29-5483-1 FWD testing data. Using material testing data as input data, falling model can simulate a set of deflection data within 5% of field data. Under the same condition, deflection data simulated by time-history model is 80% different from the field deflection data. At last, we use FWD falling model to create MODULUS backcalculation correcting procedure and find that original mean errors between backcalculated modulus and pratical modulus 66%(surface), 15.8%(subgrade) can be modified to 9.34%(surface), 5.07%(subgrade) individually through our procedure.

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