Compatibility Between Innovative Steels and Sustainable Binders: An Integrated Approach

• Grant number: 24/14827-9
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: March 01, 2025
• End date: March 31, 2028
• Field of knowledge: Engineering - Civil Engineering - Construction Industry
• Principal Investigator: Fernanda Giannotti da Silva Ferreira
• Grantee: Mariana Nuccitelli Simoes
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Steel is extensively used in construction due to its strength and malleability, yet it encounters significant challenges such as corrosion in harsh environments. When steel comes into contact with Portland cement matrices, the high pH and specific composition of the matrix can promote spontaneous steel passivation. This project aims to assess the feasibility of using steel rebar with low chromium content in both conventional and alternative cementitious matrices to enhance the durability and sustainability of civil constructions. The study proposes the production and characterization of steel rebars containing 5% chromium for use in Portland cement matrices, carbonation-cured cement, and alkali-activated cements (geopolymers). These will be compared with conventional carbon steel bars. Thermodynamic calculations using the CALPHAD method will guide and optimize the casting, forging, quenching, and tempering processes for the produced rebars. Steel will be produced in a vacuum induction furnace, followed by thermomechanical processing through rotary swaging, quenching, and tempering. Both chemical and mechanical tests will be conducted on the metallic bars (carbon steel and manufactured steel), and the binders used in the matrices will be characterized. The performance of these matrices will be compared, and the durability of both isolated and reinforced matrices will be analyzed. Additionally, electrochemical tests will be performed to evaluate the passivation and corrosion resistance of the steel in pore solutions. The anticipated outcome is that the chromium alloyed steel will demonstrate superior durability compared to conventional carbon steel across various matrices. By integrating sustainable binders to replace traditional cement, this project aims to advance the use of more durable materials in civil construction.