Electrical material data for railway track transmission line parameter studies

Identification of the equivalent distributed transmission line parameters of rail track by electromagnetic field methodology requires the numerical values of the electrical material properties of the track components. The authors describe modelling to determine the electrical conductivity, permeability and permittivity of the rails, sleepers, ballast and ground as functions of frequency, current and the environmentally influenced moisture content. Appropriate verification procedures are described based on published reference data and practical measurements. The paper concludes by presenting reference track component material data for use in numerical models.