Track Structure Design by Mathematical Models

For the design and evaluation of track structures, previous mathematical models are inadequate because they are too simplified. Recently developed finite element models are too cumbersome for the purpose of generating charts for track design and evaluation. This paper demonstrates the use of two mathematical track structure models in combination in the development of design charts. The charts should enable the optimal selection of track components in track design and the evaluation of the structural performance of existing track components in a given loading environment. The criterion for acceptable track design is the strength of the track structure on a fatigue basis. The Miner's rule is used. The charts are based on some chosen wheel-rail load magnitudes but can be used for any load magnitudes by direct proportion. For vertical wheel-rail loading, the loading configuration is based on 100-ton (90,720-kg) cars. For lateral wheel-rail loading, a single load is used.