Dynamische Charakterisierung von Schienenbefestigungskomponenten aus polymeren Werkstoffen im Eisenbahnoberbau

Research output: ThesisMaster's Thesis

Abstract

Since more than 30 years elastomers are used in different types in the railway superstructure. To check the varied requirements of stiffness, damping behavior and surface friction of the rail pads, the EN 13146 was developed a few years ago, which contains all information on the characterization of rail pads. Based on this information, a standard test setup for determining the static and low-frequency stiffness of rail pads in disassembled condition was adapted for the test field as well as for a servo-hydraulic testing machine manufactured by MTS Systems GmbH. To implement the experiment Semperit Technische Produkte GmbH provided different elastomer pads of different stiffnesses. To determine this stiffness, the force - deformation curves of the individual pads were evaluated and the stiffness was computed as a dynamic module between two defined force limits. From this feasible values the static and dynamic, low-frequency stiffness were determined. The reproducibility of the results was checked and confirmed with variations <5 % of the individual pads to each other. Furthermore, in the context of this thesis a test bench for testing the rail pads in the fully assembled state was developed, to simulate driving through curves. On the one hand it should be flexible enough to provide the different angles and the interchangeability of certain elements. On the other hand, a high stiffness of the test bench was required to carry loads of up to 120 kN. The transverse forces on the hydropulser had to be intercepted, which succeeded with the help of a crossbeam. To obtain the flexibility a portable adapter piece was developed, which could compensate the movements of the rail pad and subsequently the rail. For the determination of the slipping resistance of the rail in longitudinal direction the sleeper including liner and rail fastening system was tilted by 90 ° to the side and fixed to supports made of wood. The force in pressure mode was increased until the rail slipped through the fastening system. The obtained values agreed generally very well with those of an alternative testing institute. In determining the static stiffness of the fastening system the sleeper together with the fastening system has to be turned back again, and a spacer to compensate the pretilt was inserted. The evaluation showed that attention must be paid to the placement of the displacement transducers in when conducting the test. To carry out the fatigue test, the entire system was tilted to 33 ° and loaded dynamically. The evaluation of the first experiment showed, that the crossbeam mounted on the test bench was not suitable and had to be replaced by a crossbeam mounted on the frame of the test field. The second experiment showed that the measured displacements were significantly higher and approximately in the same range as the measured values of an alternative testing institute and that the introduced forces have an impact on the secant modulus and the dynamic modulus. This influence also appeared in the rail pad directly, which revealed a high wear after the second attempt.

Details

Translated title of the contributionDynamic chararcterization of polymeric rail fastening elements used in railway superstructure
Original languageGerman
QualificationDipl.-Ing.
Supervisors/Advisors
  • Schrittesser, Bernd, Supervisor (external), External person
  • Pinter, Gerald, Supervisor (internal)
Award date4 Apr 2014
Publication statusPublished - 2014