Acceleration-dependent lateral track resistance for the condition assessment of railway bridges with ballasted track

Lateral track resistance is essential for assessing rail track stability and the operational safety of railway lines. This contribution addresses the experimental investigation of lateral track resistance on railway bridges subjected to dynamic loads. The experiments are carried out using a large-scale test facility, replicating a representative section of a railway bridge at a scale of 1:1, thus enabling a targeted and isolated observation of the ballast superstructure's behaviour. The investigations aim to identify the influence of vertical vibrations on lateral track resistance, both for unloaded and vertically loaded track. Based on the experiments, load-dependent acceleration limits are identified, above which a significant reduction in lateral track resistance occurs. Furthermore, experimental lateral load-displacement curves depending on the vertical load and acceleration level are generated for determining lateral track stiffness. The results comprise the identified limit values for vertical accelerations and the acceleration-dependent lateral track resistances, which can be applied for condition assessment of railway bridges in the context of dynamic assessment.