Use of Conventional Site Investigation Parameters to Calculate Critical Velocity of Trains from Rayleigh Waves

This paper presents a practice-ready approach to calculating railway track critical velocity from Rayleigh waves and ground-borne vibrations with conventional site investigation parameters. Types of ground waves are discussed; equations define the wave velocities mathematically. Relationships between the terms in the equations defining Rayleigh wave velocity and hence track critical velocity are established. The reader can undertake these calculations from a standard low-cost site investigation. The design train critical velocity may be restricted to 0.7 x Rayleigh wave velocity. However, the track critical velocity is in the region of 1.1 to 1.3 x Rayleigh wave velocity.