On the influence of constructional elements on the dynamic behaviour of filler beam railway bridges - Part 1 Introduction and measurements on filler beam bridges

On the Influence of constructional elements on the dynamic behaviour of filler beam railway bridges Part 1 Introduction and measurements on filler beam bridges Enhancements of the European railway system are amongst other things mainly characterized by increased usage of high speed trains and significantly raised operating speeds To predict effects of tram loading on railway bridges for a dynamic design adequately, knowledge of the system's significant dynamic characteristics is required Only this ensures that resonance effects, which generally cannot be screened out for high speeds, can be covered analytically by reliable values Measurements especially carried out on filler beam bridges have shown though that a realistic estimation of eigen-frequencies of bridges is difficult Actual values and measured ones differ significantly in many cases In particular non-consideration of structural constraints is seen as reason for this, given that they have an immense effect on a bridge's stiffness and damping characteristics This first part of the contribution gives a brief survey on the dynamics of high-speed railway bridges Furthermore results from measurements on filler beam railway decks are presented In the forthcoming second part of the contribution the influence of particular constructional elements on the dynamic behaviour of filler beam bridges is investigated, supported by numerical studies Finally the main outcomes are discussed and proposals for an improved dynamic bridge design are made