Development of an Improved Vehicular Loading Characterization Associated with the Gage Strength of Track
American Railway Engineering Association
This report describes the development and application of a simplified technique for presenting vehicular loading information in a consistent and uniform manner. The load data, both lateral (L) and vertical (V), is used to develop a "loading severity", value (5), with which the level of loading can be equated with the associated level of damage to the track, as defined by a given rail head deflection. Specifically, it addresses the gage retaining strength of the track structure, in general, and the tie-fastener-rail system, in particular. This is done by means of a linear relationship S=L–μV where μ is the effective friction coefficient between the rail and the tie. Data were taken from five sets of fie1d and laboratory tests of track gage widening, used to validate this relationship and to determine the effective friction coefficient for conventional track. The linear relationship between lateral (L) and vertical (V) loads indicates that the equation shown above is a good approximation to the equivalent levels of loading. Examination of the test data and analysis of the effective friction for the numerous individual tests in the five series shows a normal effective friction distribution, with a mean value of 0.4 and a standard deviation of 0.1.
Vehicular loading information
Manos, Scott, Choros, & Zarembski, “Development of an Improved Vehicular Loading Characterization Associated with the Gage Strength of Track”, Bulletin of the American Railway Engineering Association, Bulletin 686, Volume 83, January - February 1982.