Parametric Investigation of a Rail Damper Design Based on a Lab-Scaled Model

Abstract

Background Track noise is one of the main issues in the development of railway networks. It is well known that rail dampers, as a cost-effective, passive means of vibration reduction, do reduce the noise; still, neither the mechanism behind their action nor the influential parameters are well understood. Purpose The main purpose of this work is to investigate the efficiency and influential parameters of a rail damper design based on a lab-scaled model of the rail-damper system and an accurate FE model. Methods Based on experimental and numerical modal analyses and the Modal Assurance Criteria (MAC) analysis, the FE model updating technique was applied to develop a highly accurate FE model of the rail-damper system for the investigated frequency range. In a further step, the developed FE model is used in a parametric analysis to assess various damper parameters with respect to the efficiency of damping rail vibrations and, therewith, radiated noise. Results The investigation performed based on FE simulations demonstrates how different material and geometric parameters of the damper influence the mobility decay rate of rail vertical vibrations. The investigated parameters are the thickness of still and rubber layers, stiffness and damping loss factor of rubber layers, and pre-force in the bolts that press the layers together. Conclusions It is shown that the FE model updating technique was capable of producing a highly accurate FE model despite the challenging properties of the real structure and that a combination of the lab-scaled model and the FE model represents a cost-effective approach.

The simplest amplitude-period formula for non-conservative oscillators

“…As a result, it delivers eigenfrequencies and eigenmodes of complex structures, which are needed to characterize the structural dynamics. Comparison between experimental and numerical modal analysis based on the Finite Element Method (FEM) is used on regular basis to check the quality of FE models and perform FE model updating (Tigh Kuchak et al, 2019;Kuchak et al, 2021). Furthermore, all real structures are non-conservative systems as damping is an inevitable part of their dynamic behavior that gives rise to energy dissipation.…”

Investigation of “Open” Superstructure Tramway Tracks in Budapest

“…Another essential component of the safe and acceptable coexistence of infrastructure and people is to make the noise generated by urban rail as bearable as possible. Although rail dampers are cost-effective and reduce noise, nevertheless, the parameters influencing their effects are not well known [35,50,51].…”

Investigation of the Glued Insulated Rail Joints Applied to CWR Tracks

“…In relation to the above-mentioned technologies and technical solutions, we can mention some special ones such as application of noise and vibration damping layers and elements [2][3][4][5][6]; ensuring lower stress in the railway permanent ways' that result and ensure lower elastic and plastic deformation in the track as well as in the layer structure [7][8]; techniques which provide special work processes, e.g. tamping of wide sleepers or side tamping that does not disturb the dense, compacted sub-ballast layer [9][10]; new and newer technologies ensuring decreased dynamic effects that can result in subsidiary failures (maybe cracking, fracturing, breaking) in the tracks' elements [11]; minimizing the wear of track elements (mainly the rails') [12] and lowering the ballast breakage [13][14][15][16].…”