Mesure en continu de la raideur dynamique d'une voie ferrée

摘要

For rail line infrastructure, good track support is one of the most important parameters for long-term stability of track geometry. Weak modulus and nonuniform support can cause poor track geometry to develop under traffic loading, which in turn will accelerate track component degradation. Thus track stiffness or modulus has been regarded, for a long time, as a structural indicator of the relevant track. Its assessment remains difficult and its value depends on the method used. In this context, a study was conducted to develop an automated technique for vertical track support measurement. This technique seeks to achieve a continuous measurement of the track stiffness under defined axle loads. The proposed method can accurately locate the track sections with large variations in stiffness. Tests performed using hydrodynamic jack loading and a road Portancemetre (bearing meter) on the traditional railway track showed that the track stiffness depends heavily on load and excitation frequency parameters. It is also shown that the technique used allows us to study the track structure behavior, while taking into account the response of the subgrade. Finally, the results were used to develop a new tool for continuous measurement of track strength.