The Effects of Critical Velocity on Railway Track at High-Speed

Investigating the Effects of Critical Velocity on the Behaviour of Railway Track at High-Speed

A SECED event with Prof Peter Woodward of Heriot-Watt University in Edinburgh

Professor Peter Woodward will be talking about the development of critical velocity effects for high speed trains over poor soils. The talk will look at the Ledsgard site in Sweden and will show how the critical velocity effect developed with train speed and what the effect was on the track response. The site is analysed using the dynamic fully coupled 3-dimensional non-linear time domain finite element program DART3D and comparisons to the measured response made. The formation of ground Mach Cones as the train speed increases is clearly shown through displaced contour plots of the track response; this is compared to video evidence of ground wave propagation at the site. The development of lateral ground vibration is also discussed through plots of the vertical peak ground velocity. Observations about the peak strains within the soil are presented in relation to the
development of non-linear effects and guidance on the analysis methodology given. The research work is put into context for the development of high-speed lines across the world and the implications for ground reinforcement to allow line speed increases discussed.

Download meeting information: SECED Flyer 291014