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The prospect of cement and concrete technologies depends on more in depth understanding of cement hydration reactions. Hydration reaction models simulate the development of the microstructures that can finally be used to estimate the cement based material properties that influence performance and service life. In this paper the multicomponent model of portland cement hydration reactions is implemented within the original Hymostruc model. The reaction kinetics of the four principal clinker minerals, C3S, C2S, C3A, C4AF, are coupled to the microstructure development. The nature of ettringite transformation to monosulfate is described by sequential chemical reactions of aluminate bearing clinker minerals. The calculated results of the model are shown and compared with systematic literature experimental results investigating the hydration of two different ordinary portland cements. Good agreement was obtained for the component fractional evolution and released heat during hydration., Structural Engineering, Civil Engineering and Geosciences

Latest developments in Hymostruc enable the possibility to evaluate the pore connectivity of an evolving microstructure while also considering the contribution of the ITZ and air voids and to examine the influence on frost durability. The numerical model is used to visualize this phenomenon and to show the contribution of both the pores and the ITZs to the continuation of capillary pore. Once the capillary pores are blocked by ongoing hydration the transport of harmful dilutions are restricted to move into the microstructure. However, distinction is made between the pore connectivity as developed in the bulk paste and the connectivity as developed by connected ITZs. A blockage of the capillary pores (pore discontinuity) as well as a blockage of the ITZs contribute to an increased depercolation of the cementitious microstructure and improve the microstructural performance. The surface durability of freeze/thaw resistance of pavements and chloride ingress is evaluated in view of the pore continuity modelling approach., Structural Engineering, Civil Engineering and Geosciences

The prospect of cement and concrete technologies depends on more in depth understanding of cement hydration reactions. Hydration reaction models simulate the development of the microstructures that can finally be used to estimate the cement based material properties that influence performance and service life. In this paper the multicomponent model of portland cement hydration reactions is implemented within the original Hymostruc model. The reaction kinetics of the four principal clinker minerals, C3S, C2S, C3A, C4AF, are coupled to the microstructure development. The nature of ettringite transformation to monosulfate is described by sequential chemical reactions of aluminate bearing clinker minerals. The calculated results of the model are shown and compared with systematic literature experimental results investigating the hydration of two different ordinary portland cements. Good agreement was obtained for the component fractional evolution and released heat during hydration., Structural Engineering, Civil Engineering and Geosciences

Latest developments in Hymostruc enable the possibility to evaluate the pore connectivity of an evolving microstructure while also considering the contribution of the ITZ and air voids and to examine the influence on frost durability. The numerical model is used to visualize this phenomenon and to show the contribution of both the pores and the ITZs to the continuation of capillary pore. Once the capillary pores are blocked by ongoing hydration the transport of harmful dilutions are restricted to move into the microstructure. However, distinction is made between the pore connectivity as developed in the bulk paste and the connectivity as developed by connected ITZs. A blockage of the capillary pores (pore discontinuity) as well as a blockage of the ITZs contribute to an increased depercolation of the cementitious microstructure and improve the microstructural performance. The surface durability of freeze/thaw resistance of pavements and chloride ingress is evaluated in view of the pore continuity modelling approach., Structural Engineering, Civil Engineering and Geosciences