Efficiency of a conductive cement-based anodic system for the application of cathodic protection, cathodic prevention and electrochemical chloride extraction to control corrosion in reinforced concrete structures

Abstract

Please cite this article as: J. Carmona, P. Garcés, M.A. Climent, Efficiency of a conductive cement-based anodic system for the application of cathodic protection, cathodic prevention and electrochemical chloride extraction to control corrosion in reinforced concrete structures, Corrosion Science (2015), doi: http://dx.doi.org/10.1016/ j.corsci. 2015.04.012 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractThis article describes the research carried out regarding the application of cathodic protection (CP) and cathodic prevention (CPrev), in some cases with a pre-treatment of electrochemical chloride extraction (ECE), on representative specimens of reinforced concrete structures, using an anodic system consisting of a graphite-cement paste applied as a coating on the surface. The aim of this research is to find out the competence of this anode for the aforementioned electrochemical treatments. The efficiency of this anode has been clearly demonstrated, as well as its capability to apply a combined process of ECE and after CP.

Influence of different ways of chloride contamination on the efficiency of cathodic protection applied on structural reinforced concrete elements

“…This was the reason to choose for CP an impressed current with a density in the high side of the conventional range. Previous researches of the same authors of this paper confirmed a good behavior of CP in the range 15-40 mA/m² [20]. No damages were detected in the GC anode after a similar period of CP application.…”

“…Homogeneous and almost continuous ∆Efeed values indicate good condition of the anode system, while sharp increases of that parameter show damages in the anode [20,29].…”

“…To set up the anode system, a graphite-cement paste (GC) was prepared by mixing graphite powder and Portland cement at 50%-50% in mass, with a water to solid mix ratio of 0.8. On that subject, the criteria stated in previous researches based on this kind of anodic system [17][18][19][20] was followed. A layer 2 mm thick of this paste was applied on the top face of each specimen, and after that all of them were placed in the curing chamber for 10 days.…”

“…For the present research, the anode system was basically composed of a thin layer of graphite-cement paste (GC), as was carried out initially for electrochemical chloride extraction [17][18][19], and recently adapted to cathodic protection. [20].…”

“…This efficiency was assessed analyzing the 4 ability of CP treatments to keep or recover protective conditions of the steel reinforcement (100 mV and 150 mV decay criterion). Besides, it was determined the reduction of Clpenetration caused by the treatments, the so-called "barrier effect" [20,21].…”