Fibrous Bridge Deck Concrete Overlay: Parameters of Investigation and Preliminary Experimental Results

This study investigates the potential benefits that synthetic fibrous additives (non-metallic) can add to the performance of bridge deck concrete overlays. Minimizing the shrinkage cracking and providing toughness and post-cracking residual strength are the principal ambitious improvement. Seven macro and micro types of synthetic fibers were selected and incorporated into the mix designs of three overlay types; latex-modified concrete (LMC), microsilica concrete (MSC), and fly ash concrete (FAC). The total fiber content was limited to 3 lb/yd3 (1.78 kg/m3) due to constructibility concerns. One macro fiber type or a combination of one macro and one micro fiber types were used resulting in a total of thirteen fibrous overlay mixes that include nine LMC, two MSC, and two FAC. Preliminary test results showed that the fibers noticeably increase the strength properties and reduce the drying shrinkage. At 3 lb/yd3 (1.78 kg/m3), the fibrous mixes are constructible expect for one macro fiber type. For similar total fiber content, the workability and finishability were enhanced when combining macro and micro fibers instead of single macro fiber. The fibrous MSC and FAC overlay mixes experienced higher compressive and flexural strengths and lower drying shrinkage than fibrous LMC mixes with similar fiber combination. However, all of the fibrous LMC overlay mixes met the required compressive and flexural strengths criteria. Workability of the fibrous LMC overlay mixes was better than the fibrous MSC and FAC. The experimental testing program is in progress to evaluate each mix’s compressive and flexural strengths, shrinkage, bond strength, permeability, toughness and residual strength, and permeability.

Language

  • English

Media Info

  • Media Type: DVD
  • Features: Figures; Photos; References; Tables;
  • Pagination: 15p
  • Monograph Title: TRB 89th Annual Meeting Compendium of Papers DVD

Subject/Index Terms

Filing Info

  • Accession Number: 01158064
  • Record Type: Publication
  • Report/Paper Numbers: 10-2233
  • Files: TRIS, TRB
  • Created Date: Jan 25 2010 11:02AM