PRESENT STATE OF TESTING OF FLEXIBLE UNDERLAYS FOR BALLAST BEDS

The DB is at present testing flexible ballast-bed underlays of varying degrees of rigidity with and without protective layer on railway structures with respect to their behaviour and their effect on the elasticity of the whole permanent way and with respect to their sound-deadening effect. Theoretical studies and actual practice have shown that as far as the permanent way is concerned the use of mats on structures is not necessary under present conditions of operation. In special cases, however, the lifting of mats to deaden noise on steel bridges can be necessary. No decision has yet been made on the use of mats for bridges and tunnels on new railway lines because the relevant studies have not yet been concluded, but provision has been made for them if neccessary. If mats are to be used, they will probably be laid loose on the surface without protective layer. The mats must meet the requirements of the technical conditions of supply and have an elasticity corresponding to a ballast number of C approximately 0.15N/cu mm. It is possible that, as a result of noise measurements, the required mat elasticity will have to be altered slightly.

  • Corporate Authors:

    Hestra Verlag

    Holzhofallee 33, Postfach 4244
    6100 Darmstadt 1,   Germany 
  • Authors:
    • KAESS, G
    • Stretz, R
  • Publication Date: 1979-9

Language

  • German

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00308434
  • Record Type: Publication
  • Source Agency: British Railways
  • Files: TRIS
  • Created Date: Feb 27 1980 12:00AM