(一) ASTM D6780 TDR 雙步驟法含水量量測表現尚可接受，惟目前 碾壓土壤視介電度量測有受到土壤種類影響，雖然依然可以以 全回歸分析參數來改善部分誤差，但最終仍然希望以降低土壤 種類誤差，文獻回顧顯示在頻率 500MHz 到 1GHz 之間，不同 土壤的介電常數變化不大，較不受土壤組構與種類之影響，有 潛力做為含水量量測之最佳頻段，有鑑於此，建議後續可進行 應用土壤介電頻譜分析來更進一步改善土壤種類影響之可 能，如能改善介電度受土種類影響，可減少反覆標定不同現地 土壤時間，將可大幅提升工程檢核效率。此外低頻之介電度資 訊可能有助於土壤密度之量測。
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(二) 單步驟法導電度與土壤性質之關係變異性大，實驗結果並不如 預期，實際上單步驟法理論上亦存在著理論上矛盾缺陷，其於 碾壓土壤含水量與乾密度檢測之適用性仍頇進一步探討，建議 必頇進一步對導電度行為進行探討。後續單步驟法亦可以考慮 以濕密度與乾密度進行標定搭配介電度與乾密度、濕密度關係 來改良單步驟法含水量與乾密度量測技術。
(三) ASTM TDR 雙步驟法同軸感測器與 MRP 感測器介電度量測正 規化後並未落在同一條回歸線上，原因主要為土壤受擾動造 成，除 6mm 多棒式感測器是為改善方案外，貫入式感測器表 顯上也有相當大的潛力，建議後續可以朝向發展貫入式感測 器。貫入式感測器目前有著容易壞的問題需要被克服，建議以 後多嘗詴找尋更理想的接合粘著劑以提高使用持久性。另外建 議可以朝著如何更有效去標定亦可能發展出省去同軸感測器 量測之步驟達到更省時更有效率之碾壓土壤工程品管之技術。
(四) 雙步驟法之施作效率主要受到需取土至模中量測之影響而無 法更加有效的降低其施作時間，為可達成非破壞性之量測以提 升量測速率可達 10 分鐘之目的，建議後續可再針對不同之非 破壞性檢測技術與 TDR 量測技術之聯合使用之可行性進行研 究探討。
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