Vibration Mitigation by Innovative Low Stiffness Rail Fastening Systems for Ballasted Track

Abstract

The collaborative work presented in this paper is part of the European project RIVAS, dedicated to the mitigation of ground-borne vibrations from rail traffic. In this paper, focus is made on innovative low stiffness fastening systems designed for ballasted track. These kinds of systems reduce ground-borne vibration by the filtering effect provided by their low stiffness in comparison to the global track stiffness. Numerical simulations performed as a first step confirmed this expected behaviour: ground vibration is strongly attenuated above a cut-off frequency at which resonance occurs. Following these results, two fastening systems designed by Pandrol (member of the RIVAS consortium) were chosen for testing, first in laboratory and then in a commercial track. The laboratory tests mainly consisted in the evaluation of the systems stiffness in realistic conditions (single sleeper in a ballast box), using an appropriate excitation. Combined with acceleration measurements, those tests confirmed the main results expected from simulations but also raised specific issues for the testing of low stiffness fastening systems. In order to be tested in a commercial track in France, some preliminary work was required on these systems; it is also presented in this paper.