加油站地下储运设备阴极防蚀之研究

Study of Cathodic Protection for Underground Structures at Gas Station

加油站的地下金属结构物除地下储运设备外 (油管与油槽 ) ,地表尚有钢筋混凝土结构 ,且混凝土中的钢筋常与地下储运设备相搭接而造成彼此间的电通性 ;由于地下储运设备的包覆阻抗多大于混凝土阻抗 ,以致在进行阴极保护时 ,保护电流较易由钢筋流过 ,造成储运设备的保护电位不足 .本研究使用外加电流式阴极保护法进行加油站的阴极防蚀 ,讨论钢筋与地下储运设备搭接或未搭接时的防蚀效果 .结果显示 ,在加油站内进行阴极保护电位评估时 ,若只采用 - 85 0mV作为保护评估标准 ,可能会产生误判结果 ,应当使用电流断电器量测结构物在阴极保护下的极化量 。

Underground structures in gas station include storage tanks, transportation pipelines, and rebar inconcrete. If rebar contacted with tanks or pipelines, effects of cathodic protection will be interfered. Present study was focused upon the effectiveness of impressed current cathodic protection for underground structures at gas station as rebar contacted with/or without tanks and pipelines. It was founded that the -850 mV criterion could not be applied to evaluate effectiveness of cathodic protection systems in gas station. Quantity of polarization of protected structures should be calculated and evaluated.