Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
권호 표지
DOI QR코드

DOI QR Code

Shear Strength Model for Slab-Column Connections

슬래브-기둥 접합부에 대한 전단강도모델

  • Received : 2010.03.25
  • Accepted : 2010.05.03
  • Published : 2010.08.31
Download PDF
⟨ Previous Next ⟩

Abstract

On the basis of the strain-based shear strength model developed in the previous study, a strength model was developed to predict the direct punching shear capacity and unbalanced moment-carrying capacity of interior and exterior slab-column connections. Since the connections are severely damaged by flexural cracking, punching shear was assumed to be resisted mainly by the compression zone of the slab critical section. Considering the interaction with the compressive normal stress developed by the flexural moment, the shear strength of the compression zone was derived on the basis of the material failure criteria of concrete subjected to multiple stresses. As a result, shear capacity of the critical section was defined according to the degree of flexural damage. Since the exterior slab-column connections have unsymmertical critical sections, the unbalanced moment-carrying capacity was defined according to the direction of unbalanced moment. The proposed strength model was applied to existing test specimens. The results showed that the proposed method predicted the strengths of the test specimens better than current design methods.

선행연구에서 제안된 변형률기반 전단강도모델에 근거하여, 슬래브-기둥 내부 및 외부접합부의 직접뚫림전단강도와 불균형휨모멘트강도를 정확하게 평가할 수 있는 강도모델을 개발하였다. 슬래브-기둥 접합부는 뚫림전단파괴에 앞서서 휨균열에 의해서 손상을 받으므로, 이 연구에서는 위험단면의 압축대에서 대부분의 전단저항이 발휘된다고 가정하였다. 슬래브 휨모멘트에 의해서 유발되는 압축수직응력이 콘크리트 압축대의 전단강도에 미치는 영향을 고려하기 위하여, 다축응력 상태에 대한 콘크리트 재료파괴기준을 이용하였다. 그 결과 위험단면의 전단성능이 휨손상의 정도에 따라서 정의되었다. 외부접합부는 비대칭적인 위험단면을 가지고 있으므로 하중재하방향을 고려하여 휨모멘트강도를 정의하였다. 실험 결과와 비교 결과, 제안된 강도모델은 현행 설계기준 보다 실험체의 강도를 더 정확하게 추정하는 것으로 밝혀졌다.

Keywords

Acknowledgement

Supported by : 한국연구재단

References

  1. MacGregor, J. G. and Wight, J. K., Reinforced Concrete: Mechanics and Design, Prentice Hall, NJ, 2005, 1132 pp.
  2. Sherif, A. G., “Behavior of Reinforced Concrete Flat Slabs,” Ph.D. Thesis, Dept. of Civil Eng., The University of Calgary, Canada, 1996.
  3. Lim, F. K. and Rangan, B. V., “Studies of Concrete Slabs with Stud Shear Reinforcement in Vicinity of Edge and Corner Columns,” ACI Structural Journal, Vol. 92, No. 5, 1995, pp. 515-525.
  4. Pralong, J., Poinconnement Symetrique des Plachers-Dalles, IBK-Bericht Nr., 131, Insitut fur Baustatik und Konstruktion ETH Zurish, 1982.
  5. Kinnunen, S. and Nylander, H., Punching of Concrete Slabs without Shear Reinforcement, Transactions No. 158. Royal Institute of Technology, Stockholm, 1960, 112 pp.
  6. 한국콘크리트학회, 콘크리트구조설계기준 해설, 2007, 523 pp.
  7. American Concrete Institute, “Building Code Requirements for Structural Concrete,” ACI 318-08. USA, 2008, 473 pp.
  8. Moehle, J. P., “Strength of Slab-Column Edge Connections,” ACI Structural Journal, Vol. 85, No. 1, 1988, pp. 89-98.
  9. Luo, Y. H. and Durrani, A. J., Equivalent Beam Model for Flat-Slab Buildings-Part II: Exterior Connections, ACI Structural Journal, Vol. 92, No. 2, 1995, pp. 250-257.
  10. Tian, Y., Jirsa, J. O., and Bayrak, O., “Nonlinear Modeling of Slab-Column Connections under Cyclic Loading,” ACI Structural Journal, Vol. 106, No. 1, 2009, pp. 30-38.
  11. 최경규, 박홍근, “무량판 슬래브-기둥 접합부에 대한 전단강도모델,” 콘크리트학회 논문집, 22권, 3호, 2010, pp. 345-356. https://doi.org/10.4334/JKCI.2010.22.3.345
  12. Kotsovos, M. D. and Pavlovic, M. N., Ultimate Limit-State Design of Concrete Structures: a New Approach, Thomas Telford, London, 1998, 208 pp.
  13. Zararis, P. D. and Papadakis, G. C., Diagonal Shear Failure and Size Effect in RC Beams without Web Reinforcement, Journal of Structural Engineering, ASCE, Vol. 127, No. 7, 2001, pp. 733-742. https://doi.org/10.1061/(ASCE)0733-9445(2001)127:7(733)
  14. Jelic, I., Pavlovic, M. N., and Kotsovos, M. D., “A Study of Dowel Action in Reinforced Concrete Beams,” Magazine of Concrete Research, Vol. 51, No. 2, 1999, pp. 131-141. https://doi.org/10.1680/macr.1999.51.2.131
  15. Tureyen, A. K. and Frosch, R. J., “Concrete Shear Strength: Another Perspective,” ACI Structural Journal, Vol. 100, No. 5, 2003, pp. 609-615.
  16. Park, H., Choi, K., and Wight, J. K., “Strain-Based Shear Strength Model for Slender Beams without Web Reinforcement,” ACI Structural Journal, Vol. 103, No. 6, 2006, pp. 783-793.
  17. Choi, K., Park, H., and Wight, J. K., “Unified Shear Strength Model for Reinforced Concrete Beams- Part I: Development,” ACI Structural Journal, Vol. 104, No. 2, 2007, pp. 142-152.
  18. Choi, K., Reda Taha, M. M., Park, H., and Maji, A. K., “Punching Shear Strength of Interior Concrete Slab-Column Connections Reinforced with Steel Fibers,” Cement and Concrete Composites, Vol. 29, No. 5, 2007, pp. 409-420. https://doi.org/10.1016/j.cemconcomp.2006.12.003
  19. Chen W. F., Plasticity in Reinforced Concrete, New York, McGraw-Hill, 1982, pp. 204-205.
  20. CSA A23.3-M04 Technical Committee, Design of Concrete Structures, Canadian Standards Associations, Toronto, Ontario, 2004, 258 pp.
  21. Kinnunen, S. and Nylander, H., Punching of Concrete Slabs without Shear Reinforcement, Transactions No. 158, Royal Institute of Technology, Stockholm, 1960, 112 pp.
  22. Bazant, Z. P. and Cao, Z., “Size Effect in Punching Shear Failure of Slabs,” ACI Structural Journal, Vol. 84, No. 1, 1987, pp. 44-53.
  23. BS 8110, Structural Use of Concrete, Part1, Code of Practice for Design and Construction, British Standards Institution, London, 1997, 168 pp.
  24. Manterola, M., “Poinconnement de Dalles Sans Armature d’effort Trenchant,” ComiteEuropeen du Beton (Hrsg.), Dalles, Structures Planes, CEB-Bull, Paris, d’Information 1966, 58 pp.
  25. FIP 12, Punching of Structural Concrete Slabs. CEB-FIP Task Group, Lausanne, Switzerland, 2001, 314 pp.
  26. 최경규, 박홍근, “불균형 휨모멘트를 받는 플랫플레이트-기둥 외부접합부의 강도,” 콘크리트학회 논문집, 15권, 3호, 2003, pp. 470-481. https://doi.org/10.4334/JKCI.2003.15.3.470

Cited by

  1. Modification of the ACI 318 Design Method for Slab-Column Connections Subjected to Unbalanced Moment vol.17, pp.10, 2014, https://doi.org/10.1260/1369-4332.17.10.1469
  2. Consideration on punching shear strength of steel-fiber-reinforced concrete slabs vol.7, pp.5, 2015, https://doi.org/10.1177/1687814015584251
  3. Retrofitting of Interior Slab-to-Column Connections for Punching Shear Using Different Techniques vol.33, pp.1, 2019, https://doi.org/10.1061/(ASCE)CF.1943-5509.0001246
  4. Punching shear resistance of strengthened reinforced concrete interior slab–column connections using ultra-high-performance strain-hardening cementitious composite material pp.2048-4011, 2019, https://doi.org/10.1177/1369433218823841