DOI QR코드

DOI QR Code

Computational optimisation of a concrete model to simulate membrane action in RC slabs

  • Hossain, Khandaker M.A. (Department of Civil Engineering, Ryerson University) ;
  • Olufemi, Olubayo O. (Department of Engineering, University of Aberdeen)
  • Received : 2003.11.13
  • Accepted : 2004.03.26
  • Published : 2004.08.25

Abstract

Slabs in buildings and bridge decks, which are restrained against lateral displacements at the edges, have ultimate strengths far in excess of those predicted by analytical methods based on yield line theory. The increase in strength has been attributed to membrane action, which is due to the in-plane forces developed at the supports. The benefits of compressive membrane action are usually not taken into account in currently available design methods developed based on plastic flow theories assuming concrete to be a rigid-plastic material. By extending the existing knowledge of compressive membrane action, it is possible to design slabs in building and bridge structures economically with less than normal reinforcement. Recent research on building and bridge structures reflects the importance of membrane action in design. This paper describes the finite element modelling of membrane action in reinforced concrete slabs through optimisation of a simple concrete model. Through a series of parametric studies using the simple concrete model in the finite element simulation of eight fully clamped concrete slabs with significant membrane action, a set of fixed numerical model parameter values is identified and computational conditions established, which would guarantee reliable strength prediction of arbitrary slabs. The reliability of the identified values to simulate membrane action (for prediction purposes) is further verified by the direct simulation of 42 other slabs, which gave an average value of 0.9698 for the ratio of experimental to predicted strengths and a standard deviation of 0.117. A 'deflection factor' is also established for the slabs, relating the predicted peak deflection to experimental values, which, (for the same level of fixity at the supports), can be used for accurate displacement determination. The proposed optimised concrete model and finite element procedure can be used as a tool to simulate membrane action in slabs in building and bridge structures having variable support and loading conditions including fire. Other practical applications of the developed finite element procedure and design process are also discussed.

Keywords

References

  1. Alan Hon, A., Geoff Taplin, G. and Riadh Al-Mahaidi, R. (2001), "Compressive membrane action in reinforced concrete one-way slabs", The Eighth East Asia-Pacific Conference on Structural Engineering and Construction, 5-7 December, Nanyang Technological University, Singapore, Paper No.1276, 8.
  2. Braestrup, M. W. (1980), "Dome effects in RC slabs: rigid plastic analysis", J. Struct. Div. ASCE, 106(ST6), 1237-1253.
  3. Cedolin, L. and Deipoli, S. (1977), "Finite element studies of shear-critical R/C beams", J. Eng. Mech. Div., ASCE, 103(EM3), 395-410.
  4. Das, S. K. (2001), "Compressive membrane action in circular reinforced concrete slabs", Masters dissertation, Dept. Engineering, University of Cambridge, UK.
  5. Eyre, J. R. (1997), "Direct assessment of safe strengths of RC slabs under membrane action", J. Struct. Eng., 123(10), 1331-1338. https://doi.org/10.1061/(ASCE)0733-9445(1997)123:10(1331)
  6. Huang, Z., Burgess, I. W. and Plank, R. J. (2003a), "Modeling membrane action of concrete slabs in composite buildings in fire. I: theoretical development", J. Struct. Eng., 129(8), August, 1093-1102. https://doi.org/10.1061/(ASCE)0733-9445(2003)129:8(1093)
  7. Huang, Z., Burgess, I. W. and Plank, R. J. (2003b), "Modeling membrane action of concrete slabs in composite buildings in fire. II: validations", J. Struct. Eng., 129(8), August, 1103-1112. https://doi.org/10.1061/(ASCE)0733-9445(2003)129:8(1103)
  8. Hung, T. Y., Nawy, E. G. (1971), "Limit strength and serviceability factors in uniformly loaded, iso-tropically reinforced two way slabs", ACI, Detroit, ACI SP-30, 301-324.
  9. Johansen, K. W. (1962), Yield Line Theory, Cement and Concrete Association, London.
  10. Keenan, W. A. (1969), "Strength and behaviour of restrained reinforced concrete slabs under static and dynamic loadings", Technical Report R621, U.S. Naval Civil Engineering Laboratory, Port Hueneme, California, April, 133.
  11. Kirkpatrick, J., et al. (1984), "Strength evaluation of M-beam bridge deck slabs", The Structural Engineer, 62B (3), Sept., 60-68.
  12. Kupfer, K. H., Hilsdorf, K. H. and Rush, H. (1969), "Behaviour of concrete under biaxial stresses", Proceedings, ACI, 66(8), 656-666.
  13. Leet, K. M. and Bernal, D. (1996), Reinforced Concrete Design, 3rd Edition, Mcgraw-Hill, New York.
  14. Moy, S. S. J. and Mayfield, B. (1972), "Load-deflection characteristics of rectangular reinforced concrete slabs", Mag. Conc. Res., 24(81).
  15. Niblock, R. A. (1986), "Compressive membrane action and the ultimate capacity of uniformly loaded reinforced concrete slabs", Ph. D. thesis, The Queen's University of Belfast, UK.
  16. Ockleston, A. E. (1955), "Load tests on a three storey reinforced concrete building in johannesburg", The Struct. Eng., 33, 304-322.
  17. Owen, D. R. J. and Figueiras, J. A. (1983), "Anisotropic elasto-plastic finite element analysis of thick and thin plates and shells", Int. J. Num. Meth. Eng., 19, 541-566. https://doi.org/10.1002/nme.1620190407
  18. Owen, D. R. J. and Figueiras, J. A. (1984), "Ultimate load analysis of reinforced concrete plates and shells including geometric nonlinear effects", Finite Element Software for Plates and Shells, by E. Hinton and D.R.J. Owen, Pineridge Press, London.
  19. Owen, D. R. J. and Hinton, E. (1980), Finite Elements in Plasticity- Theory and Practice, Pineridge Press, Swansea, UK.
  20. Park, R. (1964a), "The ultimate strength and long-term behaviour of uniformly loaded, two-way concrete slabs with partial lateral restraint at all edges", Mag. Conc. Res., 16(48), 139-152. https://doi.org/10.1680/macr.1964.16.48.139
  21. Park, R. (1964b), "Ultimate strength of rectangular concrete slabs under short-term uniform loading with edges restrained against lateral movement", Proc. the Institution of Civil Engineers, 28, 125-150. https://doi.org/10.1680/iicep.1964.10109
  22. Park, R. (1965), "The lateral stiffness and strength required to ensure membrane action at the ultimate load of a reinforced concrete slab-and-beam floor", Mag. Conc. Res., 17(50) 29-38.
  23. Peel-Cross, R. J., Gilbert, S. G., Rankin, G. I. B. and Long, A. E. (1998), "Arching action in composite metal deck concrete slabs", Proc. Third Cardington Conference, Whole Building Research: the Latest Developments, BRE, 26-27 November. pp. 30-36.
  24. Powell, D. S. (1956), "Ultimate strength of concrete panels subjected to uniformly distributed loads", Cambridge University Thesis, England.
  25. Rankin, G. I. B., et al. (1991), "Compressive membrane action strength enhancement in uniformly loaded laterally restrained slabs", The Structural Engineer, 69(16), 287-295.
  26. Rankin, G. I. B., Taylor, S. E. and Cleland, D. J. (1999), "A guide to compressive membrane action in bridge deck slabs", Design Guide for the Concrete Bridge Development Group, British Cement Association, December.
  27. Salami, A. T. (1994), "Equation for predicting the strength of fully clamped two-way reinforced concrete slabs", Proc. Inst. Civ. Engr. Structs. & Bldgs, 104, 101-107. https://doi.org/10.1680/istbu.1994.25684
  28. Salim, W. and Sebastian, W. M. (2003), "Punching shear failure in reinforced concrete slabs with compressive membrane action", ACI Struct. J., 100(4), 471-479.
  29. Skates, A. S. (1986), "Development of a design method for restrained concrete slab systems subject to concentrated and uniform loading", Ph. D. Thesis, The Queen's University of Belfast, UK.
  30. Taylor, S. E., Rankin, G. I. B. and Cleland, D. J. (1998a), "Compressive membrane action in high strength concrete bridge deck slabs", Proce. 2nd International Symposium on Concrete under Severe Conditions, Environment and Loading, CONSEC '98, Tromso, Norway, Norwegian Concrete Association, 21-24 June, 3, 1704-1713.
  31. Taylor, S. E. (2000), "Compressive membrane action in high strength concrete bridge deck slabs", Ph. D. thesis, Queen's University of Belfast, Jan.
  32. Taylor, S. E., Rankin, G. I. B. and Cleland, D. J. (1998b), "High strength concrete bridge slabs with in-plane restraint", Proce. British Cement Association Annual Conference, Southampton, England, July.
  33. Whitney, C. S. (1937), "Design of reinforced concrete members under flexure or combined flexure and direct compression", J. American Conc. Inst., 33, 483-498, March-April.
  34. Wood, R. H. (1961), Plastic and Elastic Design of Slabs and Plates, Thames and Hudson, London, 344.