"Durability and reliability of concrete infrastructure is a serious, large scale, financial and safety concern with an increasing scientific, engineering and economical focus. Although the interest for numerical modelling of cementitious materials and durability issues increases rapidly in recent years, a comprehensive knowledge on their fundamental processes is still lacking. The proposed project is interdisciplinary, bridging fundamental understanding of multiphase ionic transport in porous materials and durability based design of cementitious materials that combine computational materials science, chemistry, physics and engineering technology. The influence of the morphological effect and the level of water saturation on the ionic diffusion properties of hydrating cement pastes will be investigated using the TU Delft's HYMOSTRUC cement hydration and microstructure development model. The diffusive properties of the simulated microstructures will be analyzed by a number of developed numerical 3D network methods. These innovative numerical 3D network models will be coupled with another developed numerical code, called MultIDiff, to describe the multi-component ionic diffusion in concrete structures considering the time and space dependency of parameters. This project will advance the quality of European science, relative to the North America (USA and Canada) and Japan, in the field of numerical tools to predict durability of cementitious materials. As both institutions: the host’s, TU Delft and the fellows, University of Zagreb are actively involved in industry related projects to predict the service-life of new and existing concrete structures, the results of this project will find a direct industry application. The design based on a sound quantitative basis will make cement and concrete a more environmentally friendly, sustainable and affordable material."