The desired service quality of the whole bridge can be affected by a single dysfunctional component or by the combination of several dysfunctional components. The decrease in bridge service quality clearly depends on the degree of components’ dysfunctionality. This dependency can be modelled, among others, by Bayesian nets, which provide the time variation of each bridge component performance.
However, in order to assure a desired service quality with minimum interruptions, bridge owners launch preventative actions when the risk of service impairment, interruption or losses in life cycle costs reaches some predefined level. Implicitly the owners define herewith the accepted risk which can be different from country to country, based on social equity principles. This accepted risk depends upon the established performance goals for each component or combination of bridge components.
The QC plan mirrors these findings and is used for maintenance planning by defining a criteria for triggering maintenance interventions. Clearly, these QC plans have to be established for each individual bridge. They perform the basis for the asset management of this type of roadway infrastructure. The objective of this task is to establish a procedure, based on Bayesian nets or other heuristic rules used worldwide, which would allow the bridge owner to define a QC plan for each individual bridge.
The milestone for this task is to prepare a report with detailed explanation of the steps towards the establishment of a QC plan for different types of bridges until the middle of year 3. This outcome will constitute the basis of WG5, being also used by WG4. The main achievements will be published in refereed scientific journal papers and in international conferences. A summary of such results will be also available at both website and web 2.0 (e.g. facebook). A joint workshop in this field will be organized at the end of year 3.