鋼筋混凝土結構鋅熔射陰極防蝕應用

Zinc Metalizing for Galvanic Cathodic Protection of Reinforced Concrete

為解決鋼筋混凝土結構鋼筋腐蝕問題，陰極防蝕技術為一有效的防蝕工法，其方法有外加電流式與犧牲陽極式。鋅熔射在鋼筋混凝土結構陰極防蝕上的應用在國外已使用多年，但在國內尚無使用的經驗；為瞭解此工法施工的可行性與有效性，本研究在蘇澳港13號碼頭底板進行現場試驗評估。結果顯示，9個月的試驗期間，斷電後鋼筋電位之退極化量符合NACE International RP290-2000規範之100 mV的標準；且混凝土受海水潑濺呈水飽和狀態時，鋼筋所需的退極化時間較長，斷電瞬間混凝土的IR降較不明顯。

Cathodic protection (CP) has become an established method for the rehabilitation of reinforced concrete structures subject to chloride induced corrosion. Different types and configurations of both impressed current CP systems and sacrificial anodes are now available for different applications. A galvanic cathodic protection system using metallized zinc anodes was applied to the Su-Ao harbor, Taiwan to mitigate the corrosion of the steel reinforced wharf decks. The performance of the galvanic protection systems, following 9 months of monitoring, is encouraging. The galvanic protection current is around 9 mA/m 2, and the depolarization potential meets the National Association of Corrosion Engineers International (NACE) 100 mV criteria. It is apparent that longer periods of potential decay are required for water-saturated concrete.