Line speeds in Chipping Sodbury & Alderton Tunnels - Aerodynamic limits (TM-AERO-62)

Aerodynamically, tunnel line speeds are fixed according to a criterion based on pressure amplitude affecting train passengers and staff working in tunnels. For Chipping Sodbury and Alderton Tunnels a limiting pressure change of 3 kPa within any 3 second period is considered appropriate. For some years the line speeds...