Modeling the urban stock and lifecycles of bridges: An integrated framework for dynamic-locational material flow analysis

The paper introduces a dynamic-locational MFA model to analyze the urban stock of bridges by integrating quantity, time, and location in one framework. The model is developed to assess existing materials in the urban stock, predict future demolition activities, quantify material flows, and analyze their spatial distribution. The derived framework depends on the structural conditions to anticipate lifetime and survival. For the empirical analysis and demonstration, a dataset of >12,000 bridges in North Rhine-Westphalia was compiled to provide the required information such as location, area, type and material. The analyses demonstrate significant variability in material flows across different times and locations. Some regions exhibited exceptional material flows, while others had very low flows, highlighting the importance of temporal and spatial aspects. The results also predict significant material flows over the next two decades in the investigated region, underscoring the urgency of circular economy and closer cooperation between stakeholders.