The joints in Jointed Plain Concrete Pavements (JPCP) represent the system’s primary points of weakness. To prevent ingress of moisture and contaminants, these joints are typically sealed. Conventional sealants exhibit limited durability and must be renewed every few years. In addition, the concrete adjacent to the joints often suffers premature damage under combined environmental and mechanical loading. In this project, we propose and investigate an alternative repair concept by overlaying existing concrete joints with a thin carbon‑reinforced concrete (CRC) layer. The CRC overlay accommodates positive joint movements by forming a network of fine multiple cracks within a predefined decoupling zone. The latter implies a bituminous or flexible polymer coating acting as decoupling agent between the CRC-layer and the underlying concrete along a predefined length. It must allow the free deformation of the CRC-layer independently of the concrete substrate, in this way promoting controlled crack development. Beyond this decoupling zone the CRC-layer is bonded to the concrete substrate. To assess the performance of this composite system at a representative scale, we developed an innovative laboratory test setup that allows the experimental simulation of both positive and negative joint displacements on large-scale joint elements. The setup is instrumented to monitor crack width, crack spacing and the load displacement-history. In a comprehensive parameter study, we investigate the behavior of the joint system with various overlay configurations in terms of length of the decoupling zone and materials used as decoupling agents.