Direct field measurement of the dynamic amplification in a bridge. (15th February 2017) - Carey, Ciarán
Abstract: In this paper, the level of dynamics, as described by the Assessment Dynamic Ratio (ADR), is measured directly through a field test on a bridge in the United Kingdom. The bridge was instrumented using fiber optic strain sensors and piezo-polymer weigh-in-motion sensors were installed in the pavement on the approach road. Field measurements of static and static-plus-dynamic strains were taken over 45 days. The results show that, while dynamic amplification is large for many loading events, these tend not to be the critical events. ADR, the allowance that should be made for dynamics in an assessment of safety, is small. Highlights: The level of Assessment Dynamic Ratio is measured directly on a real bridge. The dynamic factor is found from the combined result of all large vehicle crossings. A weigh-in-motion (WIM) system is used to find the relative weights trucks. Dynamic amplification is as high as 100%, the actual probabilistic allowance is 6%. The findings have great potential for future use in bridge safety assessment.