纖維的添加提升水泥基材料的韌性。使用回收或低足跡材料控制纖維加勁水泥基材料對環境的影響。椰子纖維被廣泛研究為纖維加勁材料，具有低成本、可持續性和高拉伸韌性的特性。椰子纖維的品質和特性因地理位置等因素而異。比較不同來源的椰子纖維檢測結果可確定是否存在顯著差異，並確保其應用效果，推動綠色生產的實現。
本研究採用電化學阻抗法(Electrochemical Impedance Spectroscopy, EIS)進行試驗，根據其交流阻抗頻譜圖(Nyquist Plot)上的特徵值，並選用Han等效電路模型擬合出各電路參數值，依據各電路參數所代表之物理意義，探討纖維來源為China、India、Indonesia、Sri Lanka、Taiwan、Vietnam，含量依水泥的重量百分比為0.5%至2.5%，以及長度1、3、5公分對椰纖水泥砂漿內部之微結構所造成的影響，並同步進行抗壓試驗結果與電路參數值作相關分析。
研究結果顯示，無論纖維來源、含量、長度的變化，椰纖水泥砂漿相較於純水泥砂漿的整體電阻率低，這是因為增加纖維與基質間之孔隙率，從而擴大電流傳導路徑。不同來源椰纖水泥砂漿之固相電容皆高於純水泥砂漿，且會隨著椰纖含量上升而略微增加，可能原因為椰子纖維儲存電荷的能力較砂漿高。另外，連通電阻主導纖維水泥砂漿的電學行為，對於不同椰纖來源並沒有顯著影響，纖維含量增加有較明顯變化，纖維長度則有些微影響。此外，連通電阻與抗壓強度呈現良好的相關性，可以用於有效地預測椰子纖維水泥砂漿的水化過程並推測其抗壓強度。且不同來源椰纖水泥砂漿對於連通電阻與抗壓強度相關性並沒有顯著差異，因此證實椰子纖維水泥砂漿的通用性。另外，椰纖水泥砂漿之擴散阻抗係數較純水泥砂漿低，原因為纖維的添加可以增加水泥基材料的孔隙率和孔隙連通性，從而提高離子擴散效應。

Coconut fiber has been widely studied as a fiber reinforcement material due to its low cost, sustainability, and high tensile toughness. In this study, electrochemical impedance spectroscopy (EIS) was employed to analyze the Nyquist Plot and fit the electrical parameters of the Han’s equivalent circuit model. The effects of changing fiber source, content, and length on the microstructure of coconut fiber reinforcement mortar were investigated. Simultaneously, a correlation analysis was performed between the results of compressive strength tests and the electrical parameters. .
The research results show that regardless of variations in fiber sources, content, or length, the addition of coconut fiber reduces the bulk electrical resistivity compared to pure cement mortar. This is because it increases the porosity between the fibers and the matrix, thereby expanding conductive path. The solid-phase capacitance of fiber reinforcement mortars is higher than that of pure cement mortar, possibly due to the higher charge storage capacity of coconut fibers compared to the mortar, and it slightly increases with fiber content. Moreover, the resistance governs the electrical behavior of fiber reinforced mortars and shows no significant variation among different sources of coconut fiber, while fiber content has a more obvious effect and fiber length has a minor influence. Furthermore, there is a well correlation between the resistance and compressive strength. Additionally, different coconut fiber sources do not show significant differences in the correlation between resistance and compressive strength, confirming the universality of coconut fiber reinforcement mortars. Furthermore, the diffusion impedance coefficient of coconut fiber reinforcement mortar is lower than that of pure cement mortar, as the addition of coconut fibers can increase the porosity and connectivity of the cementitious matrix.

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