Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
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Longitudinal Elongation of Slender Reinforced Concrete Beams Subjected to Cyclic Loading

주기하중을 받는 세장한 철근콘크리트 보의 길이방향 인장변형

  • Published : 2008.12.31
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Abstract

Longitudinal elongation develops in reinforced concrete beams that exhibit flexural yielding during cyclic loading. The longitudinal elongation can decrease the shear strength and deformation capacity of the beams. In the present study, nonlinear truss model analysis was performed to study the elongation mechanism of reinforced concrete beams. The results showed that residual tensile plastic strain of the longitudinal reinforcing bar in the plastic hinge is the primary factor causing the member elongation, and that the shear-force transfer mechanism of diagonal concrete struts has a substantial effect on the magnitude of the elongation. Based on the analysis results, a simplified method for evaluating member elongation was developed. The proposed method was applied to test specimens with various design parameters and loading conditions.

휨항복 이후 주기하중을 받는 철근콘크리트 부재에서는 길이방향의 인장변형이 발생된다. 이러한 길이방향 인장변형은 철근콘크리트 보의 강도 및 변형능력을 저하시킬 수 있다. 본 연구에서는 비선형 트러스 모델 해석을 통하여 철근콘크리트 보에 발생되는 길이방향 인장변형의 메커니즘을 분석하였다. 그 결과, 길이방향 인장변형은 소성힌지에서의 길이방향 철근에 발생되는 잔류 인장 소성변형으로 인하여 발생되고, 대각 콘크리트 스트럿의 전단력 전달 메커니즘이 길이방향 인장변형의 크기에 중요한 영향을 미치는 것으로 나타났다. 이러한 분석결과를 토대로 주기거동 동안 철근콘크리트 보에 누적되는 길이방향 인장변형을 평가할 수 있는 간단한 평가식을 제안하였다, 제안된 방법은 다양한 설계변수 및 재하이력을 갖는 보 실험체에 적용되었다.

Keywords

References

  1. Paulay, T., 'Seismic Design of Concrete Structures: The Present Needs of Societies,' Proceedings of 11th World Conference on Earthquake Engineering, Paper No. 2001, Acapulco, Mexico, 1996
  2. Kim, J., Stanton, J., and MacRae, G., 'Effect of Beam Growth on Reinforced Concrete Frames,' Journal of Structural Engineering, ASCE, Vol. 130, No. 9, 2004, pp. 1333-1342 https://doi.org/10.1061/(ASCE)0733-9445(2004)130:9(1333)
  3. Kabeyasawa, T., Sanada, Y., and Maeda, M., 'Effect of Beam Axial Deformation on Column Shear in Reinforced Concrete Frames,' Proceedings of 12 th World Conference on Earthquake Engineering, Paper No. 1017, Auckland, New Zealand, 2000
  4. Lee, J. and Watanabe, F., 'Shear Deterioration of Reinforced Concrete Beams Subjected to Reversed Cyclic Loading,' ACI Structural Journal, Vol. 100, No. 4, 2003, pp. 480-489
  5. Brown, R. H. and Jirsa, J. O., 'Shear Transfer of Reinforced Concrete Beams under Reversed Loading,' ACI Special Publication 42-16, 1971, pp. 347-357
  6. T. Paulay, M. J. N. Priestley, Seismic Design of Reinforced Concrete and Masonry Buildings, John Wiley and Sons, Inc, 1992
  7. Fenwick, R. and Davidson, B., 'Elongation in Ductile Seismic Resistant Reinforced Concrete Frames,' Proceedings of Tom Paulay Symposium, Farmington Hills, Michigan, American Concrete Institute., SP 157-7, 1995, pp. 143-170
  8. Park, H. and Eom, T, 'Truss Model for Nonlinear Analysis of Reinforced Concrete Members Subject to Cyclic Loading', Journal of Structural Engineering, ASCE, Vol. 138, No. 10, 2007, pp. 1351-1363
  9. Muguruma, H., Watanabe, F., et al., 'Study on Shear Design of RC Beams Subjected to Combined Bending and Shear: Part1 and Part2,' Summaries of Technical Papers of Annual Meeting of Architectural Institute of Japan, 1988, pp. 183-186 (In Japanese)
  10. Park, H. and Eom, T., 'A Simplified Method for Estimating the Amount of Energy Dissipated by Flexure-Dominated Reinforced Concrete Members for Moderate Cyclic Deformations,' Earthquake Spectra, Vol. 22 No. 2, 2006, pp. 459-490 https://doi.org/10.1193/1.2197547
  11. Priestley, M. J. N., 'Performance Based Seismic Design,' Proceedings of the 12 th World Conference on Earthquake Engineering, Auckland, New Zealand, 2000
  12. Kinugasa, H. and Nomura, S., 'Failure Mechanism Under Reversed Cyclic Loading after Flexural Yielding,' Concrete Research and Technology, Japanese Concrete Institute, Vol. 5, No. 2, 1994, pp. 21-32. (In Japanese) https://doi.org/10.3151/crt1990.5.2_21

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