This article describes the strengthening of the Forth Road Bridge in Scotland. Due to steadily rising traffic, the bridge, originally designed to carry 2900t live load, must be upgraded to carry 8500t. When strengthened, it will also satisfy the European Union's new 40t axle loading. Bridge loads will be transferred from the cables to new steel columns built inside the four main towers; only these towers need strengthening. 60% of the total 9000t dead load on each tower leg will be transferred onto the internal column; 2000t will be offloaded at road deck level, and another 4000t at the tower top. Each 150m-high internal column consists of 45 box sections bolted together. Although its preparation was complex, installation of the new columns, slid past guide plates with only 15mm tolerance, was remarkably trouble-free. The work has been done with the help of jacks. Traffic lane closures on the bridge are forbidden, except at night. Access to the tower is along narrow, weight-restricted cycle lanes, and external climbing platforms provide the main way up the tower legs.

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    LONDON,   United Kingdom  EC1R 4QX
  • Authors:
    • Hayward, D
  • Publication Date: 1996-7-25


  • English

Media Info

  • Pagination: p. 20-1
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00729335
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Dec 12 1996 12:00AM