Electrochemical study on the chloride corrosion susceptibility of cementitious composites produced with sugarcane bagasse ash sand

Author(s)

Rezende, Mariana de A. M. ; Corradini, Patricia G. ; Sales, Almir ; Mascaro, Lucia H.

• Document type: Journal article
• Source: CONSTRUCTION AND BUILDING MATERIALS; v. 397, p. 13-pg., 2023-09-15.

Abstract

Sugarcane bagasse ash sand (SBAS) has been studied as a potential additive for reinforcement structures, but long-term (more than a week) studies on its use in test specimens have not been conducted considering the durability of these concretes. Additionally, there has been no assessment of electrochemical corrosion in cor-rosive media, such as chloride solutions. In this study, we conducted a physical and electrochemical investigation of SBAS, which partially replaces fine sand in a mortar configuration. Electrochemical impedance spectroscopy and open circuit potential monitoring techniques were used to evaluate the reinforcements in Ca(OH)2 (curing environment) and NaCl 3.5% (aggressive environment), and SEM-EDS was used to analyze the reinforcement surface. During the curing process, SBAS concrete formed a passivation film after a longer time (7-14 days) than the reference (REF) (7 days), and the passive film showed higher resistance values than the REF sample. After 191 days in the chloride medium, REF and SBAS samples presented similar corrosion resistance. Therefore, SBAS-reinforced concrete could be a sustainable and effective alternative to conventional concrete for structural applications. (AU)

• FAPESP's process: 18/16401-8 - Photocatalysts and photoelectrodes for obtaining renewable fuels
• Grantee: Lucia Helena Mascaro Sales
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC