Untersuchung einer 50 Jahre alten Spannbetonbrücke zur Genauigkeitssteigerung von Lebensdauerprognosen

Increasing the accuracy of lifetime prediction by structural monitoring of a 50-year old pre-stressed concrete bridge

Demands on the existent infrastructure are continuously rising. Today, structures, especially bridges, have to resist significantly increased loads compared to the ones scheduled during projection and erection. In course of inspections and reassessments fatigue turned out to be of high-relevance and even led to cases of severe damage in the past. In the DFG-funded research project "Precision limits of lifetime prognoses - experimental and numerical investigation of an existent bridge structure subjected to fatigue" focus has been set on substantial structural monitoring of a 50-year old pre-stressed concrete bridge located in Düsseldorf. The measures comprise among others long-time recording of strains (concrete and tendons), material testing and trial loading. It is shown how to capture and systematically reduce inherent uncertainty of lifetime predictions. Thereby the computed structural lifetime considerably increases. In a "best case scenario", where comprehensive experimental input data is at hand, single parameters (e.g.: material, traffic loads, and structural model) impact on the prognosis as well as on its belonging precision has been quantified. Therefore both, the existent as well as the newly erected structure in the context of Heerdter Dreieck in Düsseldorf which demands for specific projection measures are elucidated.