高強度混凝土中鋼筋腐蝕行為之研究

A Study of Rebar Corrosion in High Strength Concrete

本研究旨在探討鋼筋在高強度混凝土中之腐蝕行為及其對握裹強度之影響。電化學法如開路電位法、直流極化法及交流阻抗法等均應用於同一試體之腐蝕量測，同時經由數值積分法求得等量厚度之累計損失量以為評估鋼筋腐蝕之另一標準。試驗結果顯示高強度混凝土具有較佳之腐蝕耐久性，但當混凝土發生裂縫時其耐腐蝕之優勢即喪失；又高強度混凝土與鋼筋間握裹強度之折減受腐蝕影較普通強度混凝土為明顯。

This study was focused on the rebar corrosion behavior in high strength concrete. Electrochemical methods such as open circuit potential method, DC polarization method, and AC impedance method were applied to investigate the corrosion resistance of high strength concrete. In addition, a numerical integration was used to obtain the equivalent cumulative thickness loss of rebar, which can be another criterion for evaluation of rebar corrosion. Test results show that high strength concrete has better corrosion resistance than normal strength concrete before crack initiation. However, corrosion reduces the bond strength between concrete and rebar is more significant in high strength concrete.