Confinement Effect of Reinforced Concrete Members Using a Parabola-Rectangular Compressive Stress-Strain Relationship

포물선-직선 압축응력-변형률 관계를 이용한 철근콘크리트 부재의 횡구속 효과

  • Choi, Seung Won (Dept. of Civil and Construction, Chosun College of Science & Technology) ;
  • Kim, Woo (Dept. of Civil Engineering, Chonnam University)
  • 최승원 (조선이공대학교 토목건설과) ;
  • 김우 (전남대학교 토목공학과)
  • Received : 2014.05.29
  • Accepted : 2014.12.12
  • Published : 2015.02.28


In general, RC columns are reinforced by spiral or tied steel and a strength of confined concrete is more increased than this of unconfined concrete. And strength and ductility of column are increased by a confinement effect. A confinement effect is affected by concrete strength, spacing, volume and strength of confinement steel. Many researchers suggested various confinement models which reflected these parameters by many experimental results. In this study, a load-strain relationship is evaluated by a confinement model in EC2, and it is compared with Mander model, Saatchioglu-Razvi model and Cusson et al. model. As results, it is appeared that a confinement model in EC2 is able to apply all kinds of concrete strength and a consistency in sectional analysis can be secured using material models in EC2. In parameter studies using material models in EC2, a confinement effect is more affected by a confinement steel than a concrete strength.


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