An investigation into the behaviour of pneumatic tyres used on road/rail vehicles when operating on rails

This paper builds on earlier work [1] and describes a full-scale programme of tyre tests using a purpose-built tyre test rig. The tyre being studied here is a specialized tyre intended only for use with Road-Rail Vehicles (RRVs). As the name suggests these vehicles can operate on both the road and railway tracks. When operating on railway tracks, they can be used for a number of purposes. One of these is to carry out shunting operations moving heavily loaded waggons around a railway yard. In the earlier publication [1] for this work the design, manufacture and commissioning tests for a bespoke tyre test rig that could operate to test pneumatic tyres on rails was described. That rig is summarized again here along with the description of the tyre tests that consider variations in load, variations in speed and testing in wet and dry conditions. An initial study is also described where thermal imaging has been carried out to look at the temperatures generated in the tyre when operating on a rail head. For all of the tests the focus was on the generation of longitudinal tractive forces as a function of slip, this being the most important characteristic of an RRV tyre when considering the pulling power of an RRV shunting engine. The results of this study provide new insights into the friction acting between an RRV tyre and railway track and form the basis for an ongoing study to develop a new predictive tyre model to be used in simulations that can support the design of an RRV.