| 研究実績の概要 |
From the perspective of practical application of PCM overlaying method, long-term performance of composite specimens was evaluated under severe environmental conditions. The quantitative measurement of interfacial shear and tensile strength of the composite specimen with and without silica fume was done considering environmental conditions; elevated temperature, moisture and freeze-thaw cycle. After preparation of the composite specimen, sufficient curing and corresponding exposure conditions, tests (splitting tensile and shear test) was performed with autograph to evaluate interfacial bond strength between concrete and PCM under particular condition. In addition, four-point bending tests of strengthened RC beam with and without silica fume as repaired material was conducted to resemble material level test with the aim to use silica fume in practical PCM strengthening technique. Three type of strengthening material: reinforcement, CFRP grid and CFRP strand sheet was used as a strengthening bar. Strain gauges was attached to the strengthening and the main reinforcement to get strain distribution. The performance of PCM strengthened RC beams using particular strengthening bars with or without silica fume were compared under different heads, viz. failure modes, load deflection relationship, ultimate load, debonding load and, strain value and strain distribution of the strengthening bar along the beam. The ultimate load of strengthened beams considering perfect bond between substrate concrete-overlay material were also calculated and compared with the experiment results.
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