Predicting durability of novel cement-based materials

Understanding of the durability of OPC concrete has developed over more than a century of empirical testing and basic research, with the result that some deterioration processes (e.g., freezing) are quite well understood, and most are broadly understood. Given this foundation, progress can be accelerated by focusing on tests that reveal the physical properties (e.g., diffusivity, nucleation rates, and chemical potentials) that are needed in realistic models. This approach is particularly important for the development of novel cementitious systems. The long-term behavior of new systems cannot be predicted from empirical models developed for OPC; rather, it is essential to use models based on established mechanisms and measurable physical properties. Experience with OPC has revealed the nature of the factors that will control the behavior of novel cements, and numerical simulations are increasingly capable of describing real behavior by incorporating essential degrees of complexity. Rapid introduction of new materials will be facilitated by exploiting these models, which requires focusing of experimental effort on measurement of appropriate properties. This paper briefly reviews the state of modeling efforts for several classes of deterioration problems (freezing, precipitation of salts, corrosion) and identifies the properties that need to be quantified.