REPLACEMENT OR REPAIR OF OLD TRUSS BRIDGES (ABRIDGEMENT)

The results are reported of tests on 6 steel truss bridges (late 19th century) and the effects that strengthening of the deck had on the floor systm. The results of laboratory tests on stringer beams when they are stiffened with nailers and planking are also presented. The results yield a distribution factor that is less conservative than that of AASHTO. The 6 bridges were instrumented with SR-4 strain gauges. The test truck (gravel loaded 2D truck) was placed on each bridge at various positions and induced strains on the various members were recorded. The ratings for the bridges were obtained after computing the probable induced dead and live load stresses and the allowable stresses. The ratings of 3 of the 6 bridges are governed by the strength of the stringers. In most instances the low ratings were due to the fact that no lateral bracing of the compression flange is assumed. This was rectified by the attachment of wooden nailing strips as lateral bracing. Laboratory tests were conducted to evaluate their effectiveness. Models used in the studies are described, and the bridges ratings for the 6 bridges are presented.

Media Info

  • Media Type: Print
  • Features: Tables;
  • Pagination: pp 63-65
  • Monograph Title: Bridge design, testing, and evaluation
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00157816
  • Record Type: Publication
  • ISBN: 0309025826
  • Files: TRIS, TRB
  • Created Date: Sep 28 1977 12:00AM