Validation of Track Geometry Input to the Vibration Test Unit (VTU) and Endurance Capability of the VTU

摘要

This report describes a series of tests conducted at the Transportation Test Center, Pueblo, Colorado, to validate two forms of track geometry inputs to the Vibration Test Unit (VTU) in the Rail Dynamics Laboratory, capable of reproducing actual revenue track conditions. The first form consisted of reformatted Plasser geometry input produced by converting the Plasser mid-chord offset data into a Space Curve format with a special software. The second track geometry input was developed based on the Locomotive Track Hazard Detector (LTHD) concept, and was produced by processing the time histories of special axle-mounted accelerometers into a space curve format. After the identification of a suitable form of input to the VTU which closely duplicated actual track conditions, a series of endurance cycle test runs was performed to demonstrate the capability of the VTU to operate for sustained periods of time using the track geometry as the input excitation.