KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Ductility Improvement of Square RC Columns by Using Continuous Spiral Stirrup

연속 횡방향철근 개발을 통한 사각기둥의 연성화

  • 조경훈 (충북대학교 토목공학부) ;
  • 이태희 (연세대학교 건설환경공학과) ;
  • 이정빈 (연세대학교 건설환경공학과) ;
  • 김성보 (충북대학교 토목공학부) ;
  • 김장호 (연세대학교 건설환경공학과)
  • Received : 2022.07.26
  • Accepted : 2022.11.26
  • Published : 2023.04.01
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Abstract

Recently, concerns about natural disasters such as earthquakes, tsunamis and typhoons have increased. As the magnitude and frequency of earthquakes increase, research is needed to prevent structures from collapsing due to earthquake loads. Research is needed to increase the ductility of columns to prevent the collapse of structures. In this study, the ductility improvement of square columns achieved by applying spiral stirrups to square columns. Square columns reinforced with spiral stirrups are more resistant to repetitive loads such as seismic loads than columns reinforced with tie stirrups. Also, the spiral stirrups can apply better confinement to the concrete. In this study, an uniaxial compression test was conducted to evaluate the performance of columns reinforced with spiral stirrups. The results showed that the columns reinforced with spiral stirrups in both the circular and square columns showed higher compressive strength than the columns reinforced with the tie stirrups. In addition, the columns reinforced with spiral stirrups for both the square and circle columns, showed a tendency to endure the load even after the initial cracking and rebar yielding.

최근 지진, 쓰나미, 태풍 등의 자연재해에 관한 우려가 점점 커지고 있다. 지진의 규모와 빈도가 커짐에 따라 구조물이 지진하중에 의하여 붕괴되는 것을 막기 위한 연구가 필요한 실정이다. 구조물의 붕괴를 막기 위하여 기둥의 연성화를 높이는 연구가 필요하다. 본 연구에서는 사각기둥에 연속 횡방향철근을 적용하여 사각기둥의 연성화 향상을 연구하려고 한다. 연속 횡방향철근으로 보강한 사각기둥은 띠철근으로 보강한 기둥보다 지진하중과 같은 반복하중에 강하다. 또한 연속 횡방향철근은 콘크리트에 더 나은 구속력을 적용할 수 있다. 본 연구에서 연속 횡방향철근으로 보강된 기둥의 성능 평가를 위해 1축 압축 실험을 진행하였다. 그 결과 원형기둥과 사각기둥 모두에서 연속 횡방향철근으로 보강한 기둥이 띠철근으로 보강한 기둥보다 더 높은 압축강도가 나타났다. 또한, 사각기둥과 원형기둥 모두 나선철근으로 보강된 기둥에서는 초기 균열 및 항복 후에도 하중을 버티는 경향을 보였다.

Keywords

Acknowledgement

본 연구는 2022년도국문 국토교통부/국토교통과학기술진흥원 의 지원으로 수행되었음(과제번호 RS-2021-KA163381). This work is supported by the Korea Agency for Infrastructure Technology Advancement (KAIA) grant funded by the Ministry of Land, Infrastructure and Transport (Grant 22CFRP-C163381-02).

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