Seismic Capacity Evaluation of Rectangular RC Columns Strengthened with Steel Bars

Dongmin Lee; Seong-Cheol Lee; Dong-Ho Shin; Chang Kook Oh

doi:10.7734/COSEIK.2023.36.5.283

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2023 Vol.36, Issue 5 Next Page

Research Paper

Seismic Capacity Evaluation of Rectangular RC Columns Strengthened with Steel Bars 강봉으로 보강된 RC 사각기둥의 내진 성능 평가

31 October 2023. pp. 283-293

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Abstract

With the steady increase in the annual number of earthquakes in South Korea, the need to apply seismic reinforcement on public facilities has recently increased. To reinforce seismic capacity, spaced full-column-height steel bars are attached to column faces. In this study, nonlinear finite element analysis was conducted to analyze the effect of external reinforcement steel bars on the seismic capacity of RC columns with a square or rectangular cross-section. For verification, the analysis results were compared with test results. Results showed that the finite element analysis reasonably predicted the actual structural behavior of RC columns with steel bars. In addition, both the analysis and the test results showed that the failure mode was converted from brittle failure to ductile fracture, owing to the external reinforcement steel bars. Both loading capacity and ductility were increased as well. Therefore, the external reinforcement steel bar can effectively enhance the seismic capacity of existing RC columns. This study is expected to contribute to relevant research areas such as the development of design methods.

Keywords

external reinforcement

seismic

ductility

confinement effect

nonlinear analysis

최근 국내에서 연간 지진 발생 횟수가 꾸준히 증가함에 따라 공공시설물에 대한 내진 보강의 필요성이 더욱 대두되고 있다. 이 연구에서는 사각 단면을 가진 철근콘크리트 기둥에서 강봉보강의 유무에 따른 내진 성능 개선 효과를 분석하기 위해 비선형 유한요소해석을 수행하였으며, 검증을 위해 구조실험결과와 비교하였다. 분석 결과, 이 연구에서 수행한 유한요소해석이 실제 강봉보강공법을 적용한 철근콘크리트 기둥의 구조 거동을 합리적으로 잘 묘사하는 것으로 나타났다. 또한, 해석 및 실험 모두 강봉보강공법 적용으로 인해 파괴모드가 취성파괴에서 연성파괴로 전환되었으며, 강도와 연성도 모두 증가하는 것으로 나타났다. 따라서, 강봉보강공법 적용을 통해 기존 철근콘크리트 기둥의 내진 성능을 효과적으로 증진시킬 수 있는 것으로 판단된다. 이 연구의 주요 결과는 향후 설계 방안 마련 등 관련 연구에 유용할 것으로 기대된다.

키워드

외부보강

내진

연성도

구속효과

비선형 해석

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Information

Publisher :Computational Structural Engineering Institute of Korea
Publisher(Ko) :한국전산구조공학회
Journal Title :Journal of the Computational Structural Engineering Institute of Korea
Journal Title(Ko) :한국전산구조공학회 논문집
Volume : 36
No :5
Pages :283-293
Received Date : 2023-06-08
Revised Date : 2023-08-21
Accepted Date : 2023-09-04
DOI :https://doi.org/10.7734/COSEIK.2023.36.5.283

Journal of the Computational Structural Engineering Institute of Korea ISSN:1229-3059(Print) 2287-2302(Online) 한국전산구조공학회 논문집

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