Title: Practical Application and Performance of PPC Beams Reinforced With Braided FRP Bars

Author(s): T. Okamoto, S. Matsubara, M. Tanigaki, and K. Hasuo

Publication: Symposium Paper

Volume: 138

Issue:

Appears on pages(s): 875-894

Keywords: beams (supports); failure; fiber reinforced plastics; fibers; fire resistance; flexural strength; prestressed concrete; rupture; reinforcing steels; tensile strength; Structural Research

DOI: 10.14359/4141

Date: 9/1/1993

Abstract:
The authors had the opportunity to apply partially prestressed concrete (PPC) members reinforced and prestressed with braided aramid fiber bars to an actual structure. The PPC members were used as beams for an upper foundation of a seismic base-isolated story. The PPC beams were precast, pretensioned, prestressed concrete members reinforced with braided aramid fiber bars manufactured by braiding aramid fibers and epoxy resin impregnation. Braided aramid fibers were used as main reinforcement, prestressing tendons, and transverse reinforcement of the PPC beams. Design, fabrication, and construction of the beams are reported. Full-scale flexural tests were also conducted to insure the safety margins of the beams. Two specimens were prepared using aramid fiber bars and carbon fiber bars, with cross sections similar to the actual beams. The flexural capacity of the beam at rupture of tendons shows good agreement with the calculated capacity, which uses the average tensile strength of the bars. Full-scale fire-resistance tests were also conducted on two specimens with the same cross sections as the specimens for the flexural tests, although the design did not require fire resistance of the beams because of their use in the foundation. From the test results, the beams were considered to resist fire for about 2 hr.