The use of novel alternative materials to replace Portland cement can reduce the carbon footprint of concrete. But this is only effective if mixes are evaluated to obtain an in-depth understanding of the transport mechanisms, particularly unsaturated flow. This project focuses on the (long-term) transport process and related deformations, coupled with the pore structure evaluation and C-S-H content when using alternative binders. After a thorough paste characterization, a novel neutron set-up will be used to obtain for the first time a simultaneous visualization of the pore structure and moisture ingress. Long-term imbibition will be evaluated with neutron techniques making an original use of deuterated water to visualise water movement. Finally, a global and optimization strategy will allow to determine the most suitable concrete composition in terms of economy, added value, mechanical performance and sustainability. The global strategy of this project considers transport of moisture/aggressive agents, mechanical properties, cost and environmental impact. With the generated knowledge (both fundamental and industry related) an optimized mix composition will be developed based on experimental results and life cycle analysis.