Thermodynamic modeling: Success in cement science – Untapped potential in corrosion research

For more than a century, the corrosion of steel in concrete has prevailed as a complex and yet poorly understood phenomenon, with many durability design approaches relying on phenomenological or semi-empirical service life models. The increasing societal demand to maintain aging infrastructure, the development of new cementitious binders and the push towards an environmentally more benign and circular concrete economy exacerbate the need for a more comprehensive scientific understanding of the underlying physicochemical processes, particularly in the absence of long-term empirical data. This manuscript retraces the history of thermodynamic modeling in cement and concrete research, examining early concepts, the barriers to adoption, and the pivotal role of modern Gibbs free energy minimisation solvers towards its broad level of acceptance within the scientific community. We further examine the current use of thermodynamic modeling techniques in corrosion science, emphasizing the limitations of classical potential-pH stability diagrams and addressing the widespread misconception that thermodynamics and kinetics are opposing concepts. Finally, we explore the opportunity to leverage the recent developments in the field of cement science and adopt thermodynamic modeling techniques in corrosion research, thereby addressing open questions related to the corrosion of steel in concrete.