VIADUCT OVER THE RIVER MARDLE

A description is given of the design of the 200M long four- span viaduct on the z38 road which has a 1 in 14 1/2 super-elevation and is constructed of steel box girders and steel cross girders at 3M intervals supporting a concrete bridge deck on concrete piers. The author describes problems with foundations due to the unexpectedly difficult ground conditions; during excavations for the foundations it was discovered that what appeared to be solid limestone was in fact large boulders in a clay matrix. The solution to these problems was eased by using a steel superstructure. The column bases were extended and founded on volcanic tuffs or lavas at a greater depth than originally planned. The piers and east abutment were redesigned, the ingress of water was prevented by a series of 300M deep holes cement grouted at 2M centres. It is estimated that the erection of the steel superstructure offset the delays due to extra foundation work, and its comparatively light weight proved to be a major advantage in reducing the cost of the foundation design. A concrete structure of similar spans would have required better ground conditions for falsework. /TRRL/

  • Corporate Authors:

    Department of the Environment

    Room 1640 Lunar House, 40 Wellesley Road
    Croydon CR9 2EL,   England 
  • Authors:
    • Symons, G R
  • Publication Date: 1976-3

Media Info

  • Features: Figures; Photos;
  • Pagination: p. 36-37
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00138882
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Jan 16 1977 12:00AM