Technical Reports

The Effects of Accelerated Ballast Consolidation

  • 01
  • Mar
  • 1977
AUTHOR: E.G. Cunney, J.T. May, H.N. Jones
SUBJECT: Track, Track/Train Interactions
KEYWORDS: Railroad Track; Ballast; Compaction; Track Maintenance; Stability; Buckling; Lateral Resistance
ABSTRACT: The effects of accelerated ballast consolidation were tested on mainline tracks of the Boston and Maine, the Chessie, the Missouri Pacific, the Penn Central and the Saint Louis and Southwestern, and at three sites on the Southern. Tests were made before and after traffic, after surfacing and related track work had been completed, both with and without machine consolidation of the ballast in the cribs and shoulders. The resistance of individual ties and panels of track to lateral forces track settlement under traffic, and other indicators of track stability were measured. The average lateral resistance before traffic in sections of track with consolidated ballast was found to be equivalent to that reached after more than 400,000 tons (360,000 metric tons) of traffic on track with unconsolidated ballast. Settlement was found to be less in consolidated ballast, especially at joints. The differences diminished under traffic but were still evident after many thousands of tons of traffic. Some of the test results were not conclusive because of wide variations in local conditions and other factors. However, the results indicate that accelerated consolidation of ballast will be a valuable addition to track surfacing work in areas where continuous welded rail has a high probability of buckling under temperature stress after the ballast has been disturbed.