Journal of the Korea institute for structural maintenance and inspection (한국구조물진단유지관리공학회 논문집)

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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Flexural Reinforcement of Timber Beams Using Carbon Fiber Plates

탄소섬유판을 사용한 목재 보의 휨보강

  • 최진철 (한밭대학교 건축공학과) ;
  • 김승훈 (한밭대학교 건축공학과) ;
  • 이용택 (한밭대학교 건축공학과)
  • Received : 2022.11.24
  • Accepted : 2022.12.07
  • Published : 2022.12.31
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Abstract

This paper summarizes the development and evaluation of the reinforcement details of CFRP plates to improve the bending performance of wooden beams. In this study, the reinforcing technology using high-strength bolts for the end of beam were developed as reinforcement details for reinforcing wooden beams with CFRP plates by EBM method. In order to evaluate the bending performance, a bending test was conducted for the specimens with details of reinforcement such as the EBM method and the NSM method. From the experimental results, the EBM specimens without end restraints had both the CFRP plate attachment failure and the splitting failure of the wood. In the load-displacement curve, the non-reinforced specimens exhibited linear elastic behavior and then brittle fracture after the maximum load. The maximum load of the specimens reinforced by the EBM method increased by 31.5~63.0% compared to the non-reinforced specimens, and the maximum load according to the end restraints of the high-strength bolts increased by 24.0%. Based on the reinforcement amount of the same CFRP plate, EBM reinforcement was 2.67 times larger in maximum load increase rate than NSM reinforcement.

본 논문은 목재 보의 휨성능을 향상시키기 위한 CFRP 판의 보강상세 개발과 보강성능평가를 정리한 것이다. 본 연구에서 EBM 공법에 의한 CFRP 판으로 목재 보를 보강하는 상세로서 고력볼트에 의한 단부구속보강상세를 개발하였다. 이에 대한 휨성능을 평가하기 위하여 단부 구속이 없는 EBM 공법과 NSM 공법 등의 보강 상세와 함께 휨실험을 실시하였다. 실험결과로부터, 단부구속되지 않은 CFRP 판 보강실험체는 CFRP 판의 부착파괴와 목재의 쪼갬파괴가 동시에 일어났으며, 고력볼트로 단부구속된 CFRP 판 보강실험체는 목재의 쪼개짐에 의해 최종파괴되었다. 하중-변위곡선에서 무보강 실험체들은 선형탄성거동을 하다가 최대하중 이후 취성파괴되는 거동을 나타내었으며, EBM 공법으로 보강된 실험체들은 탄성변형후 휨강성 기울기가 감소되며 최대하중에 도달하는 거동을 나타내었다. EBM 공법으로 보강된 실험체들의 최대하중은 무보강 실험체들에 비하여 31.5~63.0% 증가하였으며, 고력볼트의 단부구속에 따른 최대하중은 24.0% 증가효과를 나타내었다. 동일한 CFRP 판의 보강량을 기준으로 EBM 보강이 NSM 보강에 비하여 최대하중 증가율에서 2.67배 크게 나타났다.

Keywords

Acknowledgement

본 연구는 2020년 한밭대학교 교내학술연구비의 지원을 받아 수행되었습니다(과제명: FRP를 사용한 목구조의 보강기술개발, 과제번호: 202003650001).

References

  1. Ho, S. W., Yoon, S. J., and Kim, K. S. (2016), Experimental study on structural behavior of wood frame joints strengthened with glass fiber sheet and carbon steel, Journal of the Architecutral Institute of Korea Structure & Construction, 18(2), 139-146.
  2. Kim, J. S., Cho, C. H., Shin, Y. S., and Cho, Y. H. (2010), Flexural strengthening characteristic of sleeper member traditional wooden architecture, Journal of the Korea Institute for Structural Maintance and Inspection, 14(2), 145-152.
  3. Korea Construction Standards Center. (2016), Korean Design Standard KDS 41 33 00, Seoul, Korea.
  4. Lee, Y. T., Park, J. H., Hong, S. G., and Kim, S. H. (2015), A study of bond of structural timber and carbon fiber reinforced polymer plate, Materials Science (MEDZIAGOTYRA), 21(4), 563-567.
  5. Park, K. S., Lee, S. S., and Kwak, M. K. (2020), Evaluation on flexural performance of steel plate reinforced GLT beams, Journal of Korean Association for Spatial Structures, 20(2), 39-49. https://doi.org/10.9712/KASS.2020.20.2.39
  6. Seo, S. Y., and Kim, M. S. (2013), Bond strength of near surface-mounted FRP plate in concrete corresponding to space and bond length, Journal of the Korea Concrete Institute, 25(1), 37-43. https://doi.org/10.4334/JKCI.2013.25.1.037
  7. Walline, D. R. (2016), Bond Analysis Between Fibre Reinforced Polymer (FRP) Rods and Timber Beams, B.A.Sc., University of British Columbia, Kelowna.
  8. Yoon, S. J., Ho, S. W., and Kim, K. S. (2016), An experimental study about flexural behavior of timber beam with near surface mounted CFRP Bar, Journal of the Architecutral Institute of Korea Structure & Construction, 18(2), 131-138.