000 02174nab a2200193 4500
005 20260520000857.0
008 260224s2009 xxu
245 0 0 _aCorrosion of Epoxy- and Polymer/Zinc-Coated Rebar in Simulated Concrete Pore Solution
260 _a
_b
_coct. 2009
270 _a07/07/2010 ; 07/07/2010
300 _a14 p. ; 681-694
520 _aTranscripción del resumen del autor. This work is an initial examination of mechanistic issues on the comparative corrosion performance of regular epoxy-coated rebar (ECR) and dual polymer-zinc-coated reinforcement (DCR) in simulated concrete pore solution with and without chloride ions, at polarizations from 100 mV to -1,000 mV in the saturated calomel electrode (SCE) scale and exposure periods of 1 month or longer. Both materials had intentional coating breaks exposing the base steel. Polymer adhesion degradation of DCR relative to the as-received condition was comparable to, or less than, that experienced by ECR under both anodic and cathodic polarization and with and without chloride ions. Both DCR and ECR experienced severe corrosion at breaks under strong anodic polarization with chloride ions, but distress for DCR was significantly less than for ECR. Under open-circuit conditions DCR experienced an initial high-activity period both in the presence and absence of chloride ions after which the open-circuit potential (OCP) stabilized to ~-400 mVSCE, and the exposed steel remained free of corrosion in either environment. In contrast, ECR in the presence of chlorides developed more negative OCP and visible corrosion. After the initial period of high activity, OCP consumption of the zinc exposed at the defect rim proceeded at a very low rate, both in the presence or absence of chloride ions. In the absence of chloride ions and under medium to strong cathodic polarization, DCR showed cathodic current (and hence an ability to support corrosion macrocells with through-the-steel defects) no greater than that for ECR.
581 _a10
773 0 _tCorrosion
_g65
942 _cARTICULO
100 1 _aLau, K.
_943340
100 1 _aSagüés, A.A.
_927138
999 _c171822
_d171822