Fatigue tests on rails with work hardened and drilled bolt holes after 2 years service in the severn and dove holes tunnels (E-431)

1. In 1957 it was agreed with the Chief Civil Engineer of the Western and London Midland Regions that service experiments should be made with rails having work hardened bolt holes in tunnels where conditions are extremely arduous. 2. It was agreed to lay work hardened rails alternately with...