Societal aspects of bridge management and safety in the Netherlands

The main reason for the existence of civil infrastructures is public interest. Therefore, various societal aspects should drive an infrastructure program. Civil infrastructures are long-lived as-sets. Bridges and other structures are designed for lifetimes of 50 to 100 years. A bridge can last much longer from a technical point of view, providing the original functionality it is designed for does not change too much. The functional lifetime is often dominant and the shortest. Bridges become obsolete, because they are functional outdated. A careful choice of require-ments for a bridge is crucial in fulfilling societal needs, not only now, but also in the future. Functional requirements in a decision-theoretic concept direct technical solutions to societal needs using reliability, availability, maintainability, and safety (RAMS) requirements. This will be explained in Section 2. The cost of maintenance is substantial in the long run, because it de-pends on design choices made. For this kind of problems, a life-cycle costing (LCC) approach is an absolute necessity to ensure an integral view on the various costs that have to be spent in dif-ferent time frames to operate the infrastructure. The performance of bridges and bridge ele-ments, their deterioration and its influence on the performance and effectiveness of maintenance can be evaluated from historical data. We should invest in learning from the past'. For this pur-pose, a powerful tool is data mining in bridge management systems. Results of models and data in the Netherlands will be presented in Section 3. The last section of the paper evaluates the de-cision-theoretic results that are obtained in the Netherlands so far. The need for an effective communication will be discussed in this last section as well.