This article deals with Tinsley viaduct, the original design of which was based on a series of simply supported prestressed concrete spans with a massive steel girder running down its spine. However, it was never built as such and a continuous 12,000 t steel double-decked viaduct was constructed. A design check revealed the need for strengthening the columns, the diaphragms in both longitude boxes and the supports. Straightforward stiffening of the viaducts boxes with new plates was found to be difficult, and to relieve loads by elastic sharing would mean that the necessary additional plates would have been impractically thick. Temporary propping of spans was considered until thinner plates were introduced, but this was found to be too expensive. Details are given of the design of the "coat-hanger" scheme, where new cross boxes were to span between the main longitudinal box beams on each side of each main cross box. The article concludes by explaining that reinforcement of the diaphragms above the column support would reduce their flexibility, and compression stresses in the lower bars were found to be unacceptably high. The "coathanger" scheme was abandoned at the end of 1973. /TRRL/

Media Info

  • Features: Figures;
  • Pagination: p. 23
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00127906
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Dec 29 1975 12:00AM