BRIDGE WITHIN A BRIDGE

The strengthening of Carmarthen Bridge and its approach viaducts which carry the main A40 and A48 roads over the River TRywi, is described. Inspections and load assessments showed that the acceptable carrying capacity had fallen to 18 units of hb loading. It was decided that in order to strengthen one lane of the bridge structure to a capacity of 45 units of hb loading a virtually new bridge had to be built inside the existing one. A series of reinforced concrete arch ribs were cast, independent to the existing arches, but using the same piers. The author describes how grout bags were used on the viaducts with steel frames, external steel stands, and steel beam strengthening. The development and use of grout bags, used to fill varying depths of gap between steel frames and deck soffits, is described. Sand/cement or cement grout was pumped into nylon reinforced bags of 710 mm or 480 mm circumference. (TRRL)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00105317
• Corporate Authors:

  Cement and Concrete Association

  Wexham Spring
  Slough SL3 6PL, Buckinghamshire,   England 
• Authors:
  • HARRIS, P A
• Publication Date: 1980-1

Media Info

• Features: Figures; Photos;
• Pagination: p. 12-14
• Serial:
  • CONCRETE
  • Volume: 14
  • Issue Number: 1
  • Publisher: THE CONCRETE SOCIETY
  • ISSN: 0010-5317

Subject/Index Terms

• TRT Terms: Arches; Bearing capacity; Bridges; Cast in place concrete; Grout; Reinforced concrete; Reinforced concrete bridges; Repairing; Strength of materials
• Uncontrolled Terms: Repairs
• Geographic Terms: United Kingdom
• ITRD Terms: 3085: Bearing capacity; 3455: Bridge; 4781: Cast in situ concrete; 4729: Grout; 4794: Reinforced concrete; 3635: Repair; 5544: Strength (mater); 8119: United Kingdom
• Subject Areas: Bridges and other structures; Construction; Highways; Maintenance and Preservation; I61: Equipment and Maintenance Methods;

Filing Info

• Accession Number: 00312306
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Oct 27 1980 12:00AM