Journal of the Korean Society for Advanced Composite Structures (복합신소재구조학회 논문집)

Korean Society for Advanced Composite Structures (한국복합신소재구조학회)
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Flexural Failure Design Criteria for Retrofitted RC Slabs using FRP-UHPC Hybrid System

FRP-UHPC 복합 보강기법으로 보강된 RC 슬라브의 휨 파괴를 위한 설계 조건

  • Kim, Jung Joong (Department of Civil and Environmental Engineering, Sejong University) ;
  • Noh, Hyuk-Chun (Department of Civil and Environmental Engineering, Sejong University) ;
  • Reda Taha, Mahmoud M. (Department of Civil Engineering, University of New Mexico)
  • Received : 2012.03.21
  • Accepted : 2012.05.15
  • Published : 2012.06.30
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Abstract

This study proposes flexural failure design criteria of continuous slabs enhanced by a hybrid system of fiber reinforced polymer (FRP) and ultra high performance concrete (UHPC). The proposed hybrid retrofit system is designed to be placed at the top surface of the slabs for flexural strengthening of the sections in both positive and negative moment zones. The enhancing mechanisms of the proposed system for both positive and negative moment regions are presented. The neutral axis of the enhanced sections in positive moment zone at flexural failure is enforced to be in UHPC overlay for preventing the compression in FRP. From this condition, a relationship between design parameters of FRP and UHPC is established. Although the capacity of the proposed retrofit system to enhance flexural strength and ductility is confirmed through experiments of one-way RC slabs having two continuous spans, the retrofitted slabs failed in shear. To prevent this shear failure, a design criteria of flexural failure is proposed.

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References

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