Due to increasing degradation of bridges and growing traffic loads, subsequent proofs of structural safety often cannot be successfully carried out. To ensure the operation of these bridges, monitoring systems are used in practice to record the actual impacts and structural responses, which are then integrated into safety assessments. The emerging concept of digital twins also aims to enable a more realistic assessment of bridge structures. The objective of this paper is to merge these two methods into a concept that integrates the monitoring-based safety assessment of bridges within the digital twin. To achieve this, cross-industry research was conducted for characterizing the digital bridge twin, that enables sustainable storage and interoperable utilization of all information required for bridge maintenance. The applicability of the developed concept will be validated using two bridges in Germany. The introduced concept demonstrates a considerable potential for predictive maintenance.