Better understanding of stability of turnouts in CWR track by in field measurement and numerical study

Continuous Welded Rail (CWR) has been acknowledged as the greatest technical achievement in railway technology since the second half of last century. However, by eliminating rail joints and gaps between rail sections, the ambient temperature change during the year from severe cold winter to hot summer, high thermal stress exist and change within the welded rails. In some circumstances, if the CWR structure is combined with poor track maintenance, it may cause problems such as track buckling, broken rails, or derailment. As part of ARTC's North-South Corridor Strategy and Hunter Valley (one of the major heavy haul revenue railway line in Australia, axle load is 30t) Strategy new concrete-bearer tangential turnouts have been installed to connect the new passing loops and strengthen the mainlines during the last 4 years. These concrete bearer turnouts include fixed crossing and moving point tangential turnouts, and the manufacturers include Vossloh Cogifer, PRE, Martinus Rail and VAE. Same as the old turnouts, almost all the turnouts on the main line are welded within the adjacent CWR tracks, which has significantly integrated the track structure and decreased the maintenance cost. However, regarding the turnouts which are welded into CWR track, usually they are usually under very high thermal stress which is transferred by the CWR in the longitudinal direction. In this scenario, both the stability and functionality of turnouts may be problematic.