The safety and durability of concrete structures largely depend on the ability to accurately predict their (time-dependent) structural response for which the development of appropriate modelling techniques is crucial. However, in concrete discontinuity regions such as deep beams and half joints, the strain distribution is significantly non-linear. Hence, for the design and assessment of structures, typically the static method of limit analysis is employed e.g. strut-and-tie models and stress fields. However, these design and assessment approaches lead to a conservative and hence sometimes uneconomical design and are moreover strongly deterministic. Limited information is available on how to appropriately consider uncertainties in these methods for new structures and existing structures under degradation. Furthermore, it is not clear how these uncertainties affect the structural behaviour of discontinuity regions. Therefore, a probabilistically-based weighting of possible strut-and-tie models under uncertainty is needed and a reliability-based calculation framework needs to be developed. Special attention is needed for the shift in failure mechanism due to time-dependent degradation. Consecutively, a simplified reliability-based partial factor format can be derived for these structural topologies. Finally, this approach will be validated by experimental and numerical investigations based on literature data and experiments performed in the Magnel-Vandepitte laboratory.