ADJUSTMENT BETWEEN CONSTRUCTION AND MANAGEMENT MEASURES TO STRENGTHEN BRIDGES

AVVEIING MELLON BYGNINGS-OG DRIFTSTILTAK FOR FORSTERKNING AV BRUER

Prior to 1971, loading standards on bridges were different in the scandinavian countries, although there were broad similarities. At present, about 30% of bridges are designed for axle loads less than 80 kn, and are over 40 years old. Many older bridges have gradually become too weak and too narrow for modern traffic. They can be either upgraded, strengthened or replaced. Upgrading is possible since older bridges usually had larger factors of safety. Strengthening of only secondary members is often sufficient, since older loading regulations specified large udl's but low axle loads. Main members are therefore usually quite strong. Stone arches can be grouted, steel girder bridges given more or larger girders, steel trusses can have stronger diagonals and main members. Timber decks can be strengthened or replaced by concrete slabs. Concrete decks can be provided with edge beams. Stone arch bridges can be widened by casting cantilever slabs on each side. Concrete slabs can be extended, the existing edge being strengthened by a beam. Truss bridges can be widened by constructing footpaths outside the main members. The cost of strengthening A bridge should not exceed 50% of the cost of a new bridge. /TRRL/

  • Corporate Authors:

    Nordiska Vaegtekniska Foerbundet, Sweden

    Fack
    Stockholm,   Sweden 
  • Authors:
    • TAMBS-LYCHE, P
  • Publication Date: 1977

Language

  • Norwegian

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00184391
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Jan 13 1979 12:00AM