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

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
권호 표지
DOI QR코드

DOI QR Code

Punching Shear Strength of Deck Slabs Made of Ultra High Performance Concrete

UHPC 바닥판 슬래브의 뚫림전단강도

  • Received : 2011.06.02
  • Accepted : 2011.07.11
  • Published : 2011.07.30
Download PDF
⟨ Previous Next ⟩

Abstract

Thinner and lighter structural members can be designed by utilizing the high stiffness and toughness, and high compressive strength of UHPC(ultra high performance concrete), which reaches up to 200MPa. The punching shear capacity of UHPC was investigated in this paper aiming for the application of UHPC to bridge decks. Six square slabs were fabricated and punching shear test was performed under fixed boundary condition. Different thicknesses of test slabs, which were 40mm and 70mm, were selected. The shape ratio of loading plates were ranged between 1.0~2.5. 40mm thickness slabs showed longer softening region after the peak load and, on the other hand, 70mm thickness slabs revealed a more brittle shear failure. Experimental results were analyzed using various existing punching shear predicting equations. Ductal$^{(R)}$ equation and JSCE equation better predicted for 40mm slabs, and Harajli et al. equation and ACI-Ductal$^{(R)}$ equation better suited for 70mm slabs. Nevertheless generally they didn't well predict the test results. A new punching shear equation which was derived based on the actual failure mechanism was proposed. The proposed equation appeared to better predict the punching shear strength of UHPC than other available equations.

강섬유보강 초고성능 콘크리트(UHPC)는 압축강도가 200MPa에 이르고, 강성 및 인성이 크기 때문에 이를 이용하면 구조 부재를 얇고 가볍게 설계하는 것이 가능하다. 본 논문은 UHPC를 교량의 바닥판 슬래브에 적용하기 위해서 뚫림전단(punching shear)에 대한 저항능력을 평가한 것이다. 6개의 정사각형 슬래브를 제작하여 4변 완전고정 상태에서 뚫림전단 실험을 수행하였다. 슬래브의 두께는 40mm와 70mm였고, 재하판의 형상비는 1.0~2.5 범위였다. 40mm 실험체는 최대하중 이후에 연성적인 변형률 연화구간이 길고, 70mm 실험체는 상대적으로 더 취성적인 뚫림파괴를 보였다. 기존의 여러 뚫림전단강도 평가식을 이용하여 실험결과를 분석하였는데, 두께가 작은 40mm 실험체에서는 Ductal$^{(R)}$ 및 JSCE의 식이, 그리고 70mm 실험체에서는 Harajli et al. 및 ACI-Ductal$^{(R)}$의 제안식이 상대적으로 실험에 근접한 값을 예측하였다. 그러나 전반적으로 실험결과를 잘 예측하지 못하였으므로 실제 파괴메커니즘에 근거한 새로운 식을 제안하였다. 새로 제안한 식은 실험결과를 비교적 잘 예측하는 것으로 나타났다.

Keywords

References

  1. 강수태, 홍기남, 한상훈, 김성욱, "섬유혼입률이 강섬유보강 초고강도 콘크리트의 인장연화거동에 미치는 영향", 콘크리트학회 논문집, 제21권, 제1호, 2009, pp.13-22.
  2. 건설교통부, 도로교 설계기준, 대한토목학회, 2005.
  3. 양인환, 조창빈, 김병석, "강섬유 보강 초고성능 콘크리트 프리스트레스트 거더의 휨거동 실험 연구", 콘크리트학회 논문집, 제22권, 제6호, 2010, pp.777-786.
  4. 차수원, 김기현, 김성욱, 박정준, 배성근, "초고성능 콘크리트의 수화발열 및 역학적 특성 모델", 콘크리트학회 논문집, 제22권, 제3호, 2010, pp.389-397.
  5. 최경규, 박홍근, 김혜민, "슬래브-기둥 접합부에 대한 전단강도모델", 한국콘크리트학회 논문집, 제22권, 제4호, 2010, pp.585-593.
  6. ACI 318-02, Building Code Requirements for Structural Concrete and Commentary, ACI Committee 318, 2002, pp.443.
  7. ACI 318M-08, Building Code Requirements for Structural Concrete and Commentary, ACI Committee 318, 2008, pp.430.
  8. Alexander, S. D. B. and Simmonds, S. H., "Punching shear tests of concrete slab-column joints containing fiber reinforcement", ACI Structural Journal, Vol. 89, No. 4, 1992, pp.425-432.
  9. Choi, K. K., Reda Taha, M. M., Park, H.-G. and Maji, A. K., "Punching shear strength of interior concrete slab-column connections reinforced with steel fibers", Cement & Concrete Composites, Vol. 29, Issue 5, 2007, pp.409-420. https://doi.org/10.1016/j.cemconcomp.2006.12.003
  10. Fuchs, W., Eligenhausen, R. and Breen, J. E., "Concrete capacity design (CCD) approach for fastening to concrete", ACI Structural Journal, Vol. 92, No. 1, 1995, pp.73-94.
  11. Gowripalan, N. and Gilber, R. I., Design Guidelines for Ductal Prestressed Concrete Beams, Reference Artical, The University of NSW, May 2000.
  12. Graddy, J. C., Kim, J. James, H. Whitt, N., Burns, H. and Klingner, R. E., "Punching-shear behavior of bridge decks under fatigue loading", ACI Structural Journal, Vol. 99, No. 3, May-June 2002, pp.257-266.
  13. Harajli, M. H., Maalouf, D. and Khatib, H., "Effect of fibers on the punching shear strength of slab-column connections", Cement & Concrete Composites, Vol. 17, Issue 2, 1995, pp.161-170. https://doi.org/10.1016/0958-9465(94)00031-S
  14. Harris, D. K. and Roberts-Wollmann, C. L., "Characterization of the punching shear capacity of thin ultra-high performance concrete slabs", Virginia Transportation Research Council, Charlottesville, Virginia, 2005.
  15. JSCE, Recommendations for Design and Construction of High Performance Fiber Reinforced Cement Composites with Multiple Fine Cracks(HPFRCC), Concrete Engineering Series 82, March 2008, Japan Society of Civil Engineeers.
  16. Kupfer, H. B., Hildorf, H. K. and Rusch, H., "Behavior of concrete under biaxial stresses", ACI J., Vol. 66, No. 8, 1969, pp.656-666.
  17. Naaman, A. E., Likhitruangsilp, V. and Parra- Omntesinos, G. J., "Punching shear response of high-performance fiber-reinforced cementitious composite slabs", ACI Structural Journal, Vol. 104, No. 2, 2007, pp.170-179.
  18. Narayanan, R., Darwish, I. Y. S., "Punching shear tests on steel fibre reinforced micro-concrete slabs", Magazine of Concrete Research, Vol. 39, No. 138, 1987, pp.42-50. https://doi.org/10.1680/macr.1987.39.138.42
  19. Park, H., Ulm, F-J. and Chuang, E., Model-Based Optimization of Ultra High Performance Concrete Highway Bridge Girders, CEE Report R03-01, Massachusetts Institute of Technology, Cambridge, MA, 2003.
  20. Shaaban, A. M. and Gesund, H., "Punching shear strength of steel fibers reinforced concrete flat plates", ACI Structural Journal, Vol. 91, No. 3, 1994. pp.406-414.
  21. Tan, K.-W. and Paramasivam, P., "Punching shear strength of steel siber reinforced concrete slabs", Journal of Civil Engineering Materials, Vol. 6, No. 2, 1994, pp.240-253. https://doi.org/10.1061/(ASCE)0899-1561(1994)6:2(240)
  22. Vondran, G. L., "Applications of steel fiber reinforced concrete", Concrete International: Design & Construction, Vol. 13, No. 11, 1991, pp.44-49.

Cited by

  1. Estimation of Punching Shear Strength for Ultra High Performance Concrete Thin Slab vol.15, pp.2, 2015, https://doi.org/10.9712/KASS.2015.15.2.095
  2. Tensile Stress-Crack Opening Relationship of Ultra High Performance Cementitious Composites(UHPCC) Used for Bridge Decks vol.17, pp.1, 2013, https://doi.org/10.11112/jksmi.2013.17.1.046
  3. Experimental study of concrete decks restrained by steel strap vol.167, pp.10, 2014, https://doi.org/10.1680/stbu.12.00051
  4. Structural Behavior of Steel Fiber-Reinforced Concrete Beams with High-Strength Rebar Subjected to Bending vol.20, pp.3, 2016, https://doi.org/10.11112/jksmi.2016.20.3.093
  5. Structural Design of Ultra High-Strength Concrete Non-Uniform Truss Using Strut-Tie Approach vol.18, pp.2, 2018, https://doi.org/10.9712/KASS.2018.18.2.69
  6. Steel Strap으로 횡구속된 무철근 바닥판의 정적 및 피로거동 특성 연구 vol.16, pp.5, 2011, https://doi.org/10.11112/jksmi.2012.16.5.137
  7. 100, 120 MPa급 고강도 콘크리트 적용 바닥판 적정두께 결정을 위한 실험적 연구 vol.33, pp.4, 2011, https://doi.org/10.14346/jkosos.2018.33.4.38