Model for fiber Cross-Sectional Analysis of FRP Concrete Members Based on the Constitutive Law in Multi-Axial Stress States

다축응력상태의 구성관계에 기초한 FRP 콘크리트 부재의 층분할 단면해석모델

  • 조창근 (경북대학교 방재연구소) ;
  • 김영상 (안동대학교 토목환경공학과) ;
  • 배수호 (안동대학교 토목환경공학과) ;
  • 김환석 (안동대학교 토목환경공학과)
  • Published : 2002.12.01


Among the methods for enhancement of load-carrying capacity on flexural concrete member, recently, a concept is being investigated which replaces the steel in a conventional reinforced concrete member with a fiber reinforced polymer(FRP) shell. This study focuses on modeling of the structural behavior of concrete surrounded with FRP shells in flexural bending members. A numerical model of fiber cross-sectional analysis is proposed to predict the stress and deformation state of the FRP shell and concrete. The stress-strain relationship of concrete confined by a FRP shell is formulated to be based on the constitutive law of concrete in multi-axial compressive stress state, in assuming that the compression response is dependent on the radial expansion of the concrete. To describe the FRP shell behavior, equivalent orthotropic properties of in-plane behavior from classical lamination theory are used. The present model is validated to compare with the experiments of 4-point bending tests of FRP shell concrete beam, and has well predicted the moment-curvature relationships of the members, axial and hoop strains in the section, and the enhancement of confinement effect in concrete surrounded by FRP shell.


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