Testing of slab track under heavy axle loads

In July 2003, two types of slat) tracks, were installed on the high tonnage loop at the Facility for Accelerated Service Testing, Pueblo, Colorado. Direct fixation slab track (DFST) and independent dual block track (IDBT) were installed into a 5 degrees curve. The total slab track test section is 500 ft long, consisting of 250 ft of IDBT and 250 ft of DFST. The transition from each slab to the adjacent ballasted track is in a spiral to tangent track. For 3 years, more than 170 million gross tons of heavy axle load (HAL) traffic was accumulated and the slab track test section was capable of supporting HAL train operations, while maintaining track geometry conditions for a Class 9 track. This paper summarizes part of the test results and the main conclusions of the slab track test, which is described more completely in a report published by the Portland Cement Association.