鋼筋混凝土材料為目前土木界常用之建築材料，本身擁有諸多良好工程性質，如工作性、耐久性、耐火性等，然而當結構體暴露於海邊等高鹽份環境下，該材料往往面臨鋼筋腐蝕之威脅。當鋼筋腐蝕，鋼筋表面產生氧化物(鐵鏽)沉積，氧化物結構鬆散生成後造成鋼筋體積膨脹，進而造成混凝土開裂，最終影響鋼筋混凝土結構物力學性質與耐久性。
為評估鋼筋鏽蝕程度，本研究製作固定水灰比之握裹試體，藉由改變氯離子含量使握裹試體擁有不同鋼筋鏽蝕程度，並額外製作與握裹試體配比相同之純混凝土試體，觀察氯離子對混凝土材料影響。本研究使用交流阻抗法，繪製交流電阻抗頻譜後，透過特定等校電路模型擬合，計算模型中對應之電學參數，並分別討論鋼筋與混凝土之電學性質變化。試體電學性質測量完畢後，混凝土試體與握裹試體分別進行抗壓試驗與鋼筋拉拔試驗，觀察氯離子對兩類試體之力學性質影響。因電阻抗量測現階段缺乏固定試驗流程，試驗結果往往僅適用於定性分析，因此本研究額外使用影像分析評估，試圖量化鋼筋鏽蝕程度佐證交流阻抗法之結果。
研究結果顯示，混凝土材料部份，氯離子含量會影響試體電阻率與電容值等電學參數但不影響試體抗壓強度。握裹試體部分，因本研究對鋼筋加速腐蝕試驗控管不佳，故無法以電阻率與握裹強度試驗結果評估鋼筋鏽蝕程度；另一方面，電容值於鋼筋腐蝕後有大幅上升趨勢且增量與氯含量呈正相關關係，原因為鋼筋表面氧化物結構鬆散與混凝土開裂兩者造成固液交界面面積增加所致。雖然本研究無法以電阻率評估鋼筋鏽蝕程度，但透過電容值仍可區分些微鏽蝕程度差異，其中影像分析可佐證該結果。

In order to evaluate the corrosion degree of rebar, this study made a bonding specimen with a fixed water-cement ratio. By changing the chloride ion content, the bonding specimen had different corrosion degrees, and additionally made pure concrete with the same ratio as the bonding specimen. In this study, the AC impedance method is used. The corresponding electrical parameters in the model are calculated by fitting a specific equivalent circuit, and the changes in the electrical properties of rebar and concrete are discussed separately. After the electrical properties of the specimens were measured, the concrete specimens and the bonding specimens were subjected to compression tests and rebar pull-out tests, respectively. This study additionally used image analysis and evaluation to quantify the corrosion degree of rebar to corroborate the results of the AC impedance method.
The research results show that the content of chloride ions in the concrete material will affect the electrical parameters of the specimen but not the compressive strength of the specimen.
For the part of the bonding specimen, due to the poor control of the accelerated corrosion test of rebar in this study, it is impossible to evaluate the corrosion degree of rebar with the results of resistivity and bonding strength test. On the other hand, the capacitance value has a significant upward trend after the rebar is corroded, and the increase of the value is positively correlated with the chlorine content, which is caused by the loosening of the oxide structure on the surface of the rebar and the cracking of the concrete. Although the resistivity cannot be used to evaluate the corrosion degree of rebar in this study, the difference in the degree of corrosion can still be distinguished by the capacitance value, and the image analysis can support the result.

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