Experimental analysis of longitudinal and lateral track‐bridge interaction of the ballasted track in railway bridges

Concerning dynamic assessments of railway bridges with ballasted track, the input parameters applied in the calculation model significantly influence the generated calculation results. In this context, there is still a considerable need for research, especially regarding the dynamic properties of the ballast superstructure. This contribution is dedicated to an experimental investigation of the longitudinal track‐bridge interaction (TBI), using a special large‐scale test facility as a basis. Comparisons are made between the normative specifications of EN 1991‐2 regarding stiffness properties depending on load (loaded or unloaded track) and temperature level and the actual experimentally determined behaviour. Hereby, considerable deviations between normative assumptions and reality are found. Regarding the damping properties of the longitudinal TBI, different damping mechanisms occur depending on excitation frequency and horizontal displacement amplitude. Furthermore, this contribution presents initial results of a currently ongoing research project, which includes experimental analyses of lateral track resistance on dynamically excited railway bridges. Here, the influence of vertical bridge vibrations on lateral track stiffness is investigated.