Journal of the Architectural Institute of Korea Structure & Construction (대한건축학회논문집:구조계)

Architectural Institute of Korea (대한건축학회)
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Flexural Performance of RC Beams Strengthened with NSM-GFRP Exposed to High Temperature

GFRP 표면매립공법으로 보강된 RC보의 고온노출 후 휨 성능

  • Received : 2017.11.06
  • Accepted : 2018.03.23
  • Published : 2018.04.30
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Abstract

This study evaluated the fire resisting capacity and post-fire serviceability of the concrete beams retrofitted by near surface mounted method(NSM) using GFRP plates. Main parameters in the test are grout materials and fire exposure. For the test, two types of grout materials between concrete substrate and GFRP plate were used; flame resisting epoxy and filling mortar. Four RC beam specimens were made and two of them were exposed to fire according to real scale fire curve proposed KS F 2257. After the fire exposure test, flexural test were performed to investigate the flexural performance of concrete beams including strength and deformation. From the test results, it was found that the beam retrofitted by NSM-GFRP presented higher flexural strength than that of the beam without retrofit, which indicates NSM-GFRP retrofit technologies is effective to maintain flexural strength even after fire exposure. In addition, the specimens grouted by epoxy showed good performance in strength but bad performance in ductility.

Keywords

Acknowledgement

Supported by : 한국연구재단, 국토교통부

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