An analysis of railway system gauge proving using trains equipped with polystyrene blocks

Abstract

In order to test that clearances between trains and the infrastructure are adequate, it has been a common practice on some railway administrations to perform a proving run on new or refurbished railway systems, using trains equipped with a series of frangible polystyrene blocks attached to it. If, at the end of testing, the blocks either remain intact, or have only minor damage from identifiable strikes, this provides confidence that the system is safe for running. Modern techniques of measurement and simulation are now widely used in gauging. Due to extensive validation, the results of such simulation provide sufficient evidence of safety that this alone may be used, without the need for proving runs. Computer simulation provides analysis of a far greater range of scenarios, such as loading, wear, and failure modes that cannot be tested in physical proving. By analysing the gauging system through simulation, this paper seeks to understand the results of ‘polystyrene block gauging’, and in particular whether it provides adequate evidence of safe clearances, and whether it has a place in the gauging of the modern railway.