Exploring the Combined Use of Distributed Fiber and Deformed Bar Reinforcement to Resist Shear Forces

Macro-synthetic fibers are often added to concrete mixtures as secondary reinforcement, designed to control shrinkage and temperature cracks and improve the durability of bridge superstructures. The addition of fibers to concrete improves the tensile behavior of the material, which leads to more durable concrete elements with increased ductility and better crack control. In addition to these desirable effects, the tensile strength of the fibers also contributes to the strength of the member, however this benefit is not included in current bridge design specifications. The lack of provisions regarding the use of macro-synthetic fibers as supplemental reinforcement is of detriment to the bridge construction industry because the use of fibers in PBEs and cast-in-place connections would result in a reduction of bar reinforcement and congestion, lighter members, smaller crack sizes, better distribution of localized stresses, and improved confinement and performance of member ends. Experimental data on the simultaneous use of deformed bars and distributed macro-synthetic fiber reinforcement to provide shear strength is limited, but the existing evidence suggests that the addition of fibers to beams containing deformed bar shear reinforcement improves the strength of the beams and can shift failure from brittle to ductile modes. While this limited test data suggests potential benefits of using fibers as supplemental reinforcement, the interactions and synergies between distributed fiber and deformed bar reinforcement in resisting shear is not well understood. To realize the full benefits of macro-synthetic polyolefin fiber-reinforced concrete (PFRC), additional experimental data and rational design guidelines are needed to predict the shear strength of members containing both macro-synthetic fibers and deformed bar reinforcement.


  • English


  • Status: Active
  • Funding: $70000
  • Contract Numbers:


  • Sponsor Organizations:

    Accelerated Bridge Construction University Transportation Center (ABC-UTC)

    Florida International University
    10555 W. Flagler Street
    Miami, FL  United States  33174

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Performing Organizations:

    University of Washington, Seattle

    Civil and Environmental Engineering Department
    201 More Hall, Box 352700
    Seattle, WA  United States  98195-2700
  • Principal Investigators:

    Thonstad, Travis

  • Start Date: 20220601
  • Expected Completion Date: 0
  • Actual Completion Date: 0
  • USDOT Program: University Transportation Centers

Subject/Index Terms

Filing Info

  • Accession Number: 01889304
  • Record Type: Research project
  • Source Agency: Accelerated Bridge Construction University Transportation Center (ABC-UTC)
  • Contract Numbers: 69A3551747121
  • Files: UTC, RIP
  • Created Date: Jul 30 2023 9:09PM