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Oulun elastisten vaihteiden seurantamittaukset

Research output: Book/ReportCommissioned reportProfessional

Details

Original languageFinnish
Place of PublicationHelsinki
PublisherVäylävirasto
Number of pages87
Volume18
ISBN (Electronic)978-952-317-738-3
Publication statusPublished - 10 Dec 2019
Publication typeD4 Published development or research report or study

Publication series

NameVäyläviraston tutkimuksia
PublisherVäylävirasto
Volume19
ISSN (Electronic)2490-0982

Abstract

This report concentrates on the basic structure and behavior of two new elastic
1:15.5-turnouts, which were installed in Oulu in June 2016. The main goal of this work is to measure that behavior as comprehensively as possible and compare that to the behavior of the conventional turnout structure in the short but also in long time span.

Chapter 2 goes through all the new features of these elastic turnouts and
explains the purpose of these changes compare to conventional structure,
which is still mainly use in Finland. The changes has been made especially on the
fastenings, bearers, point machines and locking systems. Many of these
solutions have already been tested in Kouvola, where two elastic 1:9-turnout
were installed in 2014. So partly, this project also concentrates to compare the
behavior between the elastic long turnouts and the elastic short turnouts.

Chapter 3 introduces the monitoring system, which focuses mainly on
measuring the vertical movements of these test turnouts. In principle, the new
elastic components have the largest affect just on the vertical deflection and
settlement of track so these things were measured on many single points but
also with a continuous method.

The results in chapter 4 shows that the elastic components are mainly working
as expected. With the help of new elastic rail pads, the loads are shared in bigger area, which decreases the dynamic impact loads in rails, bearers and ballast. The reversible deflection remained quite stable during the two-year monitoring period. In addition, the settlement of track developed rather slowly and was practically zero during the last months of measurement. Therefore, the rate of settlement was actually slower than in line track, which is quite remarkable.

During the project also some difficulties arose in the turnout structure like
intense rail side wear in the diverging track and cant problems of the concave
long bearers. Still, neither of these problems were directly caused by the elastic
structure, because these same issues were also noticed in the conventional
turnouts. The new elastic structure can increase the rail side wear in some
circumstances, but it is definitely not the main reason for that.

Result also revealed that the new spring device with the two-spring mechanism
works out well in the tip of the switch area. However, in the heel of the switch
area, that structure does not work and conventional mechanism with one fixed
rod should be used.

Field of science, Statistics Finland