Title:
Pitting Resistance Equivalent Number (PREN) Applicable to Stainless Steel Rebar in Concrete Environment
Author(s):
Mohaddeseh Abdolhosseini and Ibrahim G. Ogunsanya Synopsis:
Publication:
Symposium Paper
Volume:
366
Issue:
Appears on pages(s):
27-48
Keywords:
Pitting Resistance Equivalent Number (PREN), Stainless Steel Rebar, Cement and Concrete, Pitting Corrosion, Non-Destructive Tools (NDT), Machine Learning, Regression Model
DOI:
10.14359/51749231
Date:
10/1/2025
Abstract:
To overcome the time- and resource-intensive electrochemical assessments used to evaluate the pitting corrosion resistance of stainless steel (SS) rebar alloys, a non-destructive assessment tool such as the Pitting Resistance Equivalent Number (PREN) index is important for decision-making involving building resilient engineering structures. By addressing the limitations of the existing PREN index, initially designed for SS alloys in hightemperature acidic or neutral environments, this study sought to develop a PREN index tailored for highly alkaline ambient-temperature concrete environments through a combination of electrochemical experimental analysis and machine learning modelling. This integrated approach and newly developed PREN index account for variations in SS alloying composition, concrete alkalinity, and environmental exposure conditions, addressing the growing demand for non-destructive, time- and cost-effective, and reliable alternatives for assessing SS rebar corrosion performance.
Developed PREN will aid design of new and selection of existing SS alloys for reinforced concrete structures across diverse localities and applications. Two major formulas were reported, one for electrochemical parameters and the other for PREN related to these electrochemical parameters, each establishing their relationship with major SS alloying elements (i.e., Cr, Ni, Mo, Mn), concrete type (i.e. pH of testing solution), and concentration of deleterious species in exposure environment (i.e. chloride, sulphate). This study marks an initial step toward developing a non-destructive corrosion-performance assessment tool for civil engineering applications.
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