Asphalt roadbeds are widely used for ballasted tracks to prevent permeation of rainwater into subgrade and to reduce the growth of track irregularities. In the conventional design method of asphalt roadbeds, thicknesses of asphalt roadbeds have been specified by the resilient settlement at the surface of asphalt roadbed. According to a new performance-based design method as described in this paper, the effect of the number of passing trains is considered as well. The effects of the number of passing trains are prescribed by the fatigue criteria of asphalt mixture layer. By introducing the new design method, more rational deigns of asphalt roadbed considering traffic volumes become possible.

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