High speed railway trains place great demands upon track foundations; heavy shock loads that are intensified by even the slightest irregularity in the rails. Conventional support for railroad trackage throughout the world is coarsely crushed, dense rock and this is the material used by the Japanese National Railways for some 12,000 miles of operating lines. Unfortunately, even this heavy ballast loses its effectiveness when laid over subsoils that are quickly turned to mud by rain or subterranian water. The pounding of passing trains pumps this mud up through the space between the ballast and it is washed away, undermining the foundation for that section of track. In 1973, after intial laboratory work, three groups of experiments were begun at selected sites on tests to strengthen subgrade by chemical treatment, tests of plastic and elastomeric sheets material placed between the subgrade and ballast, accelerated physical testing of the sheet material with a vibrator. It was concluded that a physical moisture barrier was required. For this purpose, plastic sheeting apperared to be less serviceable than elastomer selected, on the basis of accelerated testing plus in situ performance was Neoprene.

  • Corporate Authors:

    Du Pont de Nemoups (EI) and Company, Incorporated

    Wilmington, DE  United States  19898
  • Publication Date: 1965-8

Media Info

  • Features: Photos;
  • Pagination: p. 964
  • Serial:
    • Elastomers Notebook
    • Issue Number: 125
    • Publisher: Du Pont de Nemoups (EI) and Company, Incorporated

Subject/Index Terms

Filing Info

  • Accession Number: 00264252
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jan 9 1975 12:00AM