Improving Punching Shear in Flat Slab by Replacing Punching Shear Reinforcement by Ultrahigh Performance Concrete

Document Type : Original Article

Authors

Civil Engineering Department, College of Engineering, Babylon University, Iraq

Abstract

Extensive studies have focussed on the issue of the failure of punching shear in flat slabs and ways to strengthen it internally, externally and the importance of this structure (flat slab), and the danger of punching shear failure in the areas of connection of the column - slab. Therefore, this study was based on strengthening the bearing capacity of the flat slab to failure of punching shear with high-performance concrete (UHPC); because it is expensive, so it is not feasible to use it for the whole slab. Therefore, the aim of the study was to replace reinforcement punching shear with UHPC and to determine its optimal use in the shear area. Six samples of flat slabs reinforced with maximum flexural steel loaded with a column  in the middle, four forms of UHPC casting instead of shear reinforcement and at two different depths were used. The results showed an  improvement in the punching shear strength of the sample cast with UHPC instead of punching shear reinforcement (ACI 318-19) and with all thickness of the slab, it to arrived twice compared to reference sample (NSC) with reinfored flexural steel only. This is the perfect application for the UHPC. It was also noted that casting UHPC with half the thickness of the slab does not give good results compared to those casting with all thicknesses, despite doubling the distance of the UHPC from all faces of the column; but it changes the failure pattern and keeps it away from the danger areas near the unwanted columns.

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  1. Dovich, L.M., "Lateral response of nonseismically detailed reinforced concrete flat slab structures", University of Michigan, (1994),
  2. Ramana, N.V., Gnaneswar, K., Sashidhar, C. and Kumar, T.N., "Behavior of high performance concrete two way slabs in punching shear", International Journal of Science and Advanced Technology, Vol. 2, No. 3, (2012), 122-126, doi.
  3. Moe, J., "Shearing strength of reinforced concrete slabs and footings under concentrated loads, Portland Cement Association, Research and Development Laboratories, (1961).
  4. Broms, C.E., "Shear reinforcement for deflection ductility of flat plates", ACI Structural Journal, Vol. 87, No. 6, (1990), 696-705, doi.
  5. Bloem, D.L. and Delevante, O.L., "Building code requirements for reinforced concrete", ACI Journal, Vol. 1, No., (1970), 77, doi.
  6. Andersson, J.L., "Punching of concrete slabs with shear reinforcement: Kungliga tekniska högskolans handlingar", (1963).
  7. Corley, W.G. and Hawkins, N.M., "Shearhead reinforcement for slabs", in Journal Proceedings. Vol. 65, (1968), 811-824.
  8. Dilger, W.H. and Ghali, A., "Shear reinforcement for concrete slabs", Journal of the Structural Division, Vol. 107, No. 12, (1981), 2403-2420, doi.
  9. Mokhtar, A.-S., Ghali, A. and Dilger, W., "Stud shear reinforcement for flat concrete plates", in Journal Proceedings. Vol. 82, No. Issue, (1985), 676-683.
  10. El-Salakawy, E.F., Polak, M.A. and Soudki, K.A., "New shear strengthening technique for concrete slab-column connections", Structural Journal, Vol. 100, No. 3, (2003), 297-304.
  11. Adetifa, B. and Polak, M.A., "Retrofit of slab column interior connections using shear bolts", ACI Structural Journal, Vol. 102, No. 2, (2005), 268.
  12. Hassanzadeh, G. and Sundquist, H., "Strengthening of bridge slabs on columns", Nordic Concrete Research-Publications-, Vol. 21, No., (1998), 23-34, doi.
  13. Ebead, U. and Marzouk, H., "Fiber-reinforced polymer strengthening of two-way slabs", Structural Journal, Vol. 101, No. 5, (2004), 650-659.
  14. Harajli, M. and Soudki, K., "Shear strengthening of interior slab–column connections using carbon fiber-reinforced polymer sheets", Journal of Composites for Construction, Vol. 7, No. 2, (2003), 145-153.
  15. Johnson, G.P. and Robertson, I.N., "Retrofit of slab-column connections using cfrp", in 13th world conference on earthquake engineering, Vancouver, BC, Canada, paper. (2004).
  16. Beiram, A. and Al-Mutairee, H., "Effect of using waste rubber as partial replacement of coarse aggregate on torsional strength of square reinforced concrete beam", International Journal of Engineering, Transactions B: Applications, Vol. 35, No. 2, (2022), 397-405, doi: 10.5829/ije.2022.35.02b.16.
  17. Esfahani, M.R., Kianoush, M.R. and Moradi, A., "Punching shear strength of interior slab–column connections strengthened with carbon fiber reinforced polymer sheets", Engineering Structures, Vol. 31, No. 7, (2009), 1535-1542, https://doi.org/10.1016/j.engstruct.2009.02.021
  18. Harajli, M., Soudki, K. and Kudsi, T., "Strengthening of interior slab–column connections using a combination of frp sheets and steel bolts", Journal of Composites for Construction, Vol. 10, No. 5, (2006), 399-409, https://doi.org/10.1061/(ASCE)1090-0268(2006)10:5(399)
  19. Sissakis, K. and Sheikh, S.A., "Strengthening concrete slabs for punching shear with carbon fiber-reinforced polymer laminates", ACI Structural Journal, Vol. 104, No. 1, (2007), 49.
  20. Erdogan, H., Zohrevand, P. and Mirmiran, A., "Effectiveness of externally applied cfrp stirrups for rehabilitation of slab-column connections", Journal of Composites for Construction, Vol. 17, No. 6, (2013), 04013008, doi: 10.1061/(ASCE)CC.1943-5614.0000389.
  21. Muteb, H.H. and Hasan, D.M., "Ultra-high-performance concrete using local materials and production methods", in IOP Conference Series: Materials Science and Engineering, IOP Publishing. Vol. 870, (2020), 012100.
  22. Hashim, A. and Ali, A., "Structural behavior of reinforced concrete horizontally curved box beam with opening", International Journal of Engineering,Transactions A: Basics, Vol. 35, No. 4, (2022), 774-783, doi: 10.5829/ije.2022.35.04a.17.
  23. Honarvar, E., Sritharan, S., Matthews Rouse, J. and Aaleti, S., "Bridge decks with precast uhpc waffle panels: A field evaluation and design optimization", Journal of Bridge Engineering, Vol. 21, No. 1, (2016), 04015030, https://doi.org/10.1061/(ASCE)BE.1943-5592.0000775
  24. Haber, Z.B. and Graybeal, B.A., "Lap-spliced rebar connections with uhpc closures", Journal of Bridge Engineering, Vol. 23, No. 6, (2018), 04018028, https://doi.org/10.1061/(ASCE)BE.1943-5592.0001239
  25. Afefy, H.M. and El-Tony, E.-T.M., "Punching shear resistance of strengthened reinforced concrete interior slab–column connections using ultra-high-performance strain-hardening cementitious composite material", Advances in Structural Engineering, Vol. 22, No. 8, (2019), 1799-1816, https://doi.org/10.1177/1369433218823841
  26. Lampropoulos, A.P., Duncan, J.N. And Tsioulou, O.T., "Punching shear resistance of uhpfrc", in 20th Congress of IABSE, New York City 2019: The Evolving Metropolis–Report, International Association for Bridge and Structural Engineering (IABSE Vol. 114, (2019), 867-872.
  27. Harris, D.K., "Characterization of punching shear capacity of thin uhpc plates", Virginia Tech, (2004),
  28. Joh, C., Hwang, H. and Kim, B., "Punching shear and flexural strengths of ultra high performance concrete slabs", High Performance Structures and Materials IV, Vol. 97, (2008), 97-106.
  29. Graddy, J.C., Kim, J., Whitt, J.H., Burns, N.H. and Klingner, R.E., "Punching-shear behavior of bridge decks under fatigue loading", Structural Journal, Vol. 99, No. 3, (2002), 257-266, doi.
  30. Park, H., "Model-based optimization of ultra high performance concrete highway bridge girders", Massachusetts Institute of Technology, (2003),
  31. Moreillon, L., "Shear strength of structural elements in high performance fibre reinforced concrete (HPFRC)", Université Paris-Est, (2013),
  32. Aaleti, S., Petersen, B. and Sritharan, S., Design guide for precast uhpc waffle deck panel system, including connections. 2013, United States. Federal Highway Administration.
  33. Zohrevand, P., Yang, X., Jiao, X. and Mirmiran, A., "Punching shear enhancement of flat slabs with partial use of ultrahigh-performance concrete", Journal of Materials in Civil Engineering, Vol. 27, No. 9, (2015), 04014255, https://doi.org/10.1061/(ASCE)MT.1943-5533.0001219
  34. Specification, I.S., "No. 5/1984, portland cement", Central Organization for Standardization & Quality Control (COSQC), Baghdad, Iraq, (1984).
  35. specification No, I., "Natural sources for gravel that is used in concrete and construction", (1984).
  36. ASTM, "C1240-04 standard specification for the use of silica fume as a mineral admixture in hydraulic cement concrete, mortar and grout", in American Society for Testing and Materials.
  37. ASTM, "C494-05, standard specification for chemical admixtures for concrete", in American Society for Testing and Materials.
  38. ASTM, D., "6751-15a standard specification for biodiesel fuel blend stock (b100) for distillate fuels", in American Society for Testing and Materials. (2015).
  39. Committee, A., "Building code requirements for structural concrete (aci 318-08) and commentary, American Concrete Institute. (2008).
  40. Shwalia, A.S.I., Al-Salim, N.H.A. and Al-Baghdadi, H.M., "Enhancement punching shear in flat slab using mortar infiltrated fiber concrete", Civil Engineering Journal, Vol. 6, No. 8, (2020), 1457-1469, doi: 10.28991/cej-2020-03091560.
  41. ACI, "Prc-239-18: Ultra-high performance concrete", (2018).
  42. Kadhim, M.M., Saleh, A.R., Cunningham, L.S. and Semendary, A.A., "Numerical investigation of non-shear-reinforced uhpc hybrid flat slabs subject to punching shear", Engineering Structures, Vol. 241, (2021), 112444, https://doi.org/10.1016/j.engstruct.2021.112444
  43. de Sousa, A.M., Lantsoght, E.O., Genikomsou, A.S., Krahl, P.A. and Mounir, K., "Behavior and punching capacity of flat slabs with the rational use of uhpfrc: Nlfea and analytical predictions", Engineering Structures, Vol. 244, (2021), 112774, https://doi.org/10.1016/j.engstruct.2021.112774