Bridges are essential transport infrastructure components that are subjected to degradation due to dynamic loads and environmental impacts. Continuous condition monitoring is essential to ensure the safe and economical use of the structures until the end of their life cycle. Predictive maintenance can be implemented using modern information and communication technologies such as the digital twin (DT) combined with structural health monitoring methods. DTs are virtual real-time representations of structures that collect, evaluate, and provide data for informed decision-making. However, a unified approach still needs to be developed for application in the civil engineering domain. This paper proposes a concept to implement modular DT for bridge structures based on the linked data approach. Modularity is realized by use cases that integrate existing heterogeneous data sources providing a closed view of an aspect. An exemplary implementation of one use case is realized using a containerbased approach.