Extensive Modeling of Peculiar Hydration in Fine Micro-Pore Structures Applicable to Integrated Thermodynamic Analysis for Portland Cement

Abstract

Although applications of low water-to-cement ratio mixtures to practical structures have been increasing to enhance seismic resistance and long-term durability in recent years, it was experimentally observed that such a mixture causes peculiar hydration under long-term normal or high temperature curing. On the other hand, excessive hydration was revealed in the analysis using the original model, compared with the experiment in such an environment, because un-hydrated cement particles and existing condensed water reacted more significantly in the model. This study aims to enhance the integrated multiscale thermodynamic analysis, which is able to predict structural behavior in various conditions in a unified approach, by incorporating recent technical evolutions for its reverification and extending the original model to resolve the above peculiar concerns. Hence, the extensive modeling of continuous hydration considering spatial condensed water in fine micro-pore structures was proposed. Further, coupling of the integrated analysis with the extensive model was conducted, providing good agreement with time-dependent deformation experiments at different temperatures. Eventually, the validity and practical benefit of this study were demonstrated.

Keywords

• integrated multiscale thermodynamic analysis
• low water-to-cement ratio
• high temperature
• condensed water
• time-dependent deformation