Effect of Cathodic Protection on Reinforced Concrete with Fly Ash Using Electrochemical Noise.

Jorge García-Contreras,Citlalli Gaona-Tiburcio,Irene López-Cazares,Jesús Jáquez-Muñoz,Juan Carlos Ibarra Castillo,Erick Maldonado-Bandala,Guillermo Sanchéz-Díaz,Javier Olguín-Coca,Demetrio Nieves-Mendoza,Facundo Almeraya-Calderón,Luis Daimir López-León

doi:10.3390/ma14092438

Abstract

Corrosion of steel reinforcement is the major factor that limits the durability and serviceability performance of reinforced concrete structures. Impressed current cathodic protection (ICCP) is a widely used method to protect steel reinforcements against corrosion. This research aimed to study the effect of cathodic protection on reinforced concrete with fly ash using electrochemical noise (EN). Two types of reinforced concrete mixtures were manufactured; 100% Ordinary Portland Cement (OCP) and replacing 15% of cement using fly ash (OCPFA). The specimens were under-designed protected conditions (−1000 ≤ E ≤ −850 mV vs. Ag/AgCl) and cathodic overprotection (E < −1000 mV vs. Ag/AgCl) by impressed current, and specimens concrete were immersed in a 3.5 wt.% sodium chloride (NaCl) Solution. The analysis of electrochemical noise-time series showed that the mixtures microstructure influenced the corrosion process. Transients of uniform corrosion were observed in the specimens elaborated with (OPC), unlike those elaborated with (OPCFA). This phenomenon marked the difference in the concrete matrix’s hydration products, preventing Cl− ions flow and showing passive current and potential transients in most specimens.

Highlights

In the construction industry, corrosion of steel reinforcement is one of the main issues
(Zero land Cement (OCP) and the other with replacing 15% of cement using fly ash (OCPFA), Resistance immersed in 3.5 wt. % in NaCl solutions
The results showed the benefits of employ supplementary cementitious materials (SCM) with observed in the specimens elaborated with (OPC)

Summary

Introduction

Corrosion of steel reinforcement is one of the main issues. An efficient method to control steel reinforcement corrosion in concrete structures is the impressed current cathodic protection (ICCP). Predominantly electrochemical cathodic and anodic reactions can cause small transients in electrical charges on the electrode These transients manifest in potential and current noise exploited in a corrosion map [34,35]. This research aimed to study the Effect of cathodic protection on reinforced concrete with fly ash using electrochemical noise. ≤ −850 mV vs Ag/AgCl) and cathodic overprotection (E < −1000 mV vs Ag/AgCl) by impressed current, and specimens concrete were immersed in a 3.5 wt.% sodium chloride (NaCl) Solution This concentration was used to simulate an aggressive environment that contains chlorides where civil works can be built based on reinforced concrete

Reinforced Concrete Specimens

System of Protection and Cathodic Overprotection

Power Spectral Density PSD Analysis

Findings

Conclusions