The number of railway ballast particles in contact with a sleeper may be relatively small. The discrete and non-uniform nature of these contacts may cause breakage and wear. This article explores the use of pressure paper to record the loading history of sleeper to ballast particle contacts over 3 million loading cycles in full size tests. The results demonstrate that the actual contact area may be less than 1% of the total, and that the number of individual contacts is in the hundreds. Under sleeper pads, a finer ballast grading, a shallower shoulder slope and changes to the sleeper material are found to increase the number and area of contacts.
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