SOME CONSIDERATIONS IN WIDENING AND REHABILITATION OF BRIDGES

Bridge rehabilitation, whether required for repairs, strengthening, or widening, requires an insight into unique structural problems. These problems are compounded if modifications must be accomplished while maintaining traffic and if modifications alter the structural characteristics of the existing structure. This paper deals with solutions employed on two widening and rehabilitation projects. Widening the Hackensack River Bridge on the New Jersey Turnpike required integrating the superstructure with the existing superstructure. Techniques of jacking the widening main members against the existing system, inducing compatible cambers and ensuring proper load distribution, are described. This paper describes foundation additions to main river piers which were integrated by temporarily leaving a gap between the foundations. This permitted elastic shortening of new piles under pier dead load, and prevented overloading the existing piles. A classic example of fatigue failure is illustrated. Welding of fills caused a geometrical notch at the toe of welds, producing a crack through the main members of brackets and floorbeams. Widening the I-83 bridge over the Susquehanna River in Harrisburg required an inspection which revealed rivet failures at bracket tie plates. These failures appear to correlate with findings by researchers at Lehigh University (1). Unfastening the bracket tie plates from the main girders is discussed as well as other design considerations resulting from unfastening tie plates near the girder supports. /Author/

Media Info

  • Media Type: Print
  • Features: Figures; Photos; References; Tables;
  • Pagination: pp 56-63
  • Monograph Title: Bridge Engineering. Volume 1
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00183747
  • Record Type: Publication
  • ISBN: 0309026962
  • Files: TRIS, TRB
  • Created Date: Dec 3 1978 12:00AM