Monitoring structural deterioration of railway turnout systems via dynamic wheel/rail interaction

‘Big data’ obtained from wayside detection systems and sensors installed on board a train show that actual loading history for a railway track is rather dynamic and transient. The dynamic loadings due to train and track interactions redistribute from the rails to the rail pad, from the rail pad to the railway sleeper, and from the railway sleeper to the underlying ground. Dynamic content redistributed onto each layer of track is also filtered by energy dissipation characteristic of materials and structures. As a critical infrastructure, railway turnout is a structural grillage system used to divert a train to other directions or other tracks. The wheel–rail contact over the crossing transfer zone often causes detrimental impact loads that rapidly deteriorate the turnout and its components. The dynamic responses of wheel–rail interaction depend largely on the non-smooth trajectory or wearing condition of crossing geometry. In reality, a railway line spreads over a large distance and monitoring such rail infrastructure is one of the challenges in rail industry. This paper presents a methodology and application to evaluate and monitor the structural deterioration of railway turnout systems in an Australian urban rail network. The method has integrated numerical train/track simulations, axle box acceleration and ride quality data obtained from the calibrated track inspection vehicle “AK Car”.