The Post-Fire Strength of Deformed Steel Bars for Prestressed Concrete and its Evaluation Method |
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Shigeaki BABA, Shintaro MICHIKOSHI and Yutaka KOBAYASHI |
Post-fire tensile tests were performed on thermo-mechanically treated steel bars for prestressed concrete to be used in ultra-high-strength concrete buildings. Heating conditions were based on cross-sectional finite difference analyses of a typical RC column, to be exposed to 30- to 180-minute long ISO-834 fires. The hardness of the test samples was measured not only by the JIS-based hardness measurement method but also by using an ultrasonic hardness tester. The agreement of the hardnesses obtained from the methods is quite good, and the ultrasonic hardness tester provides enough information to assess the post-fire structural viability of the PC bars. |
keywords: |
deformed steel bars for prestressed concrete, fire, repair, high-strength concrete, ultrasonic hardness testing, non-destructive testing |