本文探讨了在不同 pH和Cl- 含量的模拟混凝土孔隙液介质中 ,混凝土中钢筋的腐蚀电化学行为 .电化学技术测试结果表明 ,正常情况下 ,钢筋在混凝土中受到高碱性环境的保护 ,耐蚀性好 .但随着介质 pH的降低、Cl- 含量的上升 ,钢筋腐蚀电流升高 ;动电位阳极极化曲线的测试表明 ,钢筋的维钝电流增大 ,击穿电位负移 ,混凝土中钢筋的耐蚀性下降 .这是钢筋表面钝性受破坏的缘故 .
The corrosion behavior of reinforcing steel in concrete in chloride free and chloride contaminated simulated concrete solutions was studied by electrochemical technique.The results showed that the reinforcing steel exhitibted different corrosion characteristics in the different solutons.In general ,the steel in concrete was protected in the test solutions with no salt or the lower concentration of NaCl.When the concentration of NaCl is larger than 70%,however,the corrosion behavior of the steel varied considerably,and the corrosion rate increased as pH fell and the concentration of Cl - increased.
[1 ] MehtaPK .Concretedurability fiftyyearsprogress[C].Proc .of 2ndInter .Conf.onConcreteDurability ,ACISP1 2 6 - 1 ,1 991 ,1～ 31 .
[2 ] KitowskiCJ ,WheatH .G .Effectofchloridesonreinforcingsteelexposedtosimulatedconcretesolutions .Corrosion[J].1 997,5 3(3) :2 1 6～ 2 2 6 .
[3] SyedEhteshamHussain ,AhmadS .Al Gahtani,Rasheeduzzafar .Chloridethresholdforcorrosionofrein forcementinconcrete .ACIMaterialsJournal[J].1 996 ,93(6 ) :5 34～ 5 38.
[4 ] HoarTP .TheProductionandBreakdownofthepassivityofmetals .CorrosionScience[J],1 96 7(7) :341～35 5 .
[5 ] AlvarezMG ,GalveleJR .TheMechanismofpittingofhighpurityironinNaClsolutions .CorrosionScience[J].1 984,2 4(1 ) :2 7～ 48.
[6 ] HausmanCA .Steelinconcrete :Howdoesitoccur ?MaterialsProtection[J].1 96 7,6 (1 1 ) :1 9～ 2 3.
