DOI QR코드

DOI QR Code

Behaviour of steel-fibre-reinforced concrete beams under high-rate loading

  • Behinaein, Pegah (Institute of Infrastructure and Environment, School of the Built Environment, Heriot-Watt University) ;
  • Cotsovos, Demetrios M. (Institute of Infrastructure and Environment, School of the Built Environment, Heriot-Watt University) ;
  • Abbas, Ali A. (School of Architecture, Computing and Engineering, University of East London)
  • 투고 : 2018.05.16
  • 심사 : 2018.09.11
  • 발행 : 2018.09.25

초록

The present study focuses on examining the structural behaviour of steel-fibre-reinforced concrete (SFRC) beams under high rates of loading largely associated with impact problems. Fibres are added to the concrete mix to enhance ductility and energy absorption, which is important for impact-resistant design. A simple, yet practical non-linear finite-element analysis (NLFEA) model was used in the present study. Experimental static and impact tests were also carried out on beams spanning 1.3 meter with weights dropped from heights of 1.5 m and 2.5 m, respectively. The numerical model realistically describes the fully-brittle tensile behaviour of plain concrete as well as the contribution of steel fibres to the post-cracking response (the latter was allowed for by conveniently adjusting the constitutive relations for plain concrete, mainly in uniaxial tension). Suitable material relations (describing compression, tension and shear) were selected for SFRC and incorporated into ABAQUS software Brittle Cracking concrete model. A more complex model (i.e., the Damaged Plasticity concrete model in ABAQUS) was also considered and it was found that the seemingly simple (but fundamental) Brittle Cracking model yielded reliable results. Published data obtained from drop-weight experimental tests on RC and SFRC beams indicates that there is an increase in the maximum load recorded (compared to the corresponding static one) and a reduction in the portion of the beam span reacting to the impact load. However, there is considerable scatter and the specimens were often tested to complete destruction and thus yielding post-failure characteristics of little design value and making it difficult to pinpoint the actual load-carrying capacity and identify the associated true ultimate limit state (ULS). To address this, dynamic NLFEA was employed and the impact load applied was reduced gradually and applied in pulses to pinpoint the actual failure point. Different case studies were considered covering impact loading responses at both the material and structural levels as well as comparisons between RC and SFRC specimens. Steel fibres were found to increase the load-carrying capacity and deformability by offering better control over the cracking process concrete undergoes and allowing the impact energy to be absorbed more effectively compared to conventional RC members. This is useful for impact-resistant design of SFRC beams.

키워드

참고문헌

  1. ABAQUS (2018), Version 6.12-3 Documentation, http://www.3ds.com/products-services/simulia/products/abaqus
  2. Abbas, A.A., Pullen, A.D. and Cotsovos, D.M. (2010), "Structural response of RC wide beams under low-rate and impact loading", Mag. Concrete Res., 62, 723-740. https://doi.org/10.1680/macr.2010.62.10.723
  3. Abbas, A.A., Syed Mohsin, S.M. and Cotsovos, D.M. (2016), "A simplified finite element model for assessing steel fibre reinforced concrete structural performance", Comput. Struct., 173, 31-49. https://doi.org/10.1016/j.compstruc.2016.05.017
  4. Abbas, A.A., Syed Mohsin, S.M., Cotsovos, D.M. and Ruiz-Teran, A.M. (2014), "Seismic response of steel fibre reinforced concrete beam-column joints", Eng. Struct., 59, 261-283. https://doi.org/10.1016/j.engstruct.2013.10.046
  5. Abbas, A.A., Syed Mohsin, S.M., Cotsovos, D.M. and Ruiz-Teran, A.M. (2014), "Shear behaviour of SFRC simply-supported beams", ICE Proc. Struct. Build., 167(SB9), 544-558. https://doi.org/10.1680/stbu.12.00068
  6. Abbas, A.A., Syed Mohsin, S.M., Cotsovos, D.M. and Ruiz-Teran, A.M. (2014), "Nonlinear analysis of statically-indeterminate SFRC columns", Struct. Concrete, 15(1), 94-105. https://doi.org/10.1002/suco.201300004
  7. Abbas, A.A., Syed Mohsin, S.M., Cotsovos, D.M. and Ruiz-Teran, A.M. (2014), "Statically-indeterminate SFRC columns under cyclic loads", Adv. Struct. Eng., 17(10), 1403-1417. https://doi.org/10.1260/1369-4332.17.10.1403
  8. Behinaein, P., Cotsovos, D.M. and Abbas, A.A. (2016), "FE modelling of SFRC beams under impact loads", ECCOMAS Congress 2016 VII European Congress on Computational Methods in Applied Sciences and Engineering, Eds. M. Papadrakakis, V. Papadopoulos, G. Stefanou, and V. Plevris, Crete Island, Greece, June.
  9. British Standard Institution (2013), Eurocode 8: Design of Structures for Earthquake Resistance-Part 1: General Rules, seismic actions and rules for buildings. BS EN 1998-1:2004+A1:2013 Incorporating corrigenda July 2009, January 2011 and March 2013.
  10. British Standard Institution (2014), Eurocode 2: Design of Concrete Structures-Part 1-1: General Rules and Rules for Buildings, BS EN 1992-1-1:2004+A1:2014, Incorporating corrigenda January 2008, November 2010 and January 2014.
  11. Cotsovos, D.M. (2010), "A simplified approach for assessing the load-carrying capacity of reinforced concrete beams under concentrated load applied at high rates", Int. J. Impact Eng., 37(8), 907-917. https://doi.org/10.1016/j.ijimpeng.2010.01.005
  12. Cotsovos, D.M. and Pavlovic, M.N. (2012), "Modelling of RC Beams under Impact Loading", ICE Proc. Struct. Build., 165, 2, 77-94. https://doi.org/10.1680/stbu.2012.165.2.77
  13. Cotsovos, D.M., Stathopoulos, N.D. and Zeris, C. (2008), "Fundamental behaviour of RC beams subjected to high rates of concentrated loading", ASCE J. Struct. Eng., 134, 1839-1851. https://doi.org/10.1061/(ASCE)0733-9445(2008)134:12(1839)
  14. Destree, X. (2001), "Steel fibre reinforcement for suspended slabs", Concrete, 35(8), 58-59.
  15. Hughes, G. and Spiers, D.M. (1982), "An investigation on the beam impact problem", Cement Concrete Association, Technical Report 546.
  16. Kishi, N., Khasraghy, S.G. and Kon-No, H. (2011), "Numerical simulation of reinforced concrete beams under consecutive impact loading", ACI Struct. J., 108(4), 444-452.
  17. Kotsovos, M.D. (2015), Finite-Element Modelling of Structural Concrete: Short-Term Static and Dynamic Loading Conditions, Boca Raton, CRC Press.
  18. Kotsovos, M.D. and Pavlovic, M.N. (1995), Structural Concrete, Finite-Element Analysis for Limit-state Design, Thomas Telford, London, UK.
  19. Kotsovos, M.D., Pavlovic, M.N. and Cotsovos, D.M. (2008), "Characteristic features of concrete behaviour: Implications for the development of an engineering finite-element tool", Comput. Concrete, 5(3), 243-260. https://doi.org/10.12989/cac.2008.5.3.243
  20. Lok, T.S. and Xiao, J.R. (1999), "Flexural strength assessment of steel fibre reinforced concrete", J. Mater. Civil Eng., 11(3), 188-196. https://doi.org/10.1061/(ASCE)0899-1561(1999)11:3(188)
  21. May, I.M., Chen, Y., Owen, D.R.J., Feng, Y.T. and Thiele, P.J. (2006), "Reinforced concrete beams under drop-weight impact loads", Comput. Concrete, 3(2-3), 79-90. https://doi.org/10.12989/cac.2006.3.2_3.079
  22. Naaman, A.E. and Gopalaratnam,V.S. (1983), "Impact properties of steel fibre reinforced concrete in bending", Int. J. Cement Compos. Lightw. Concrete, 5(4), 225-233. https://doi.org/10.1016/0262-5075(83)90064-7
  23. Nadine, M.P. (2011), "Healthy doses of steel fibre 'Clear' rebar congestion in concrete coupling beams", ENR: Eng. News-Record, 266(2), 36.
  24. RILEM Technical Committees (2003), "RILEM TC 162-TDF: Test and design methods for steel fibre-reinforced concrete, final recommendation: ${\sigma}-{\varepsilon}$ design method", Mater. Struct., 36, 560-567.
  25. Robins, P., Austin, S. and Jones, P. (2002), "Pull-out behaviour of hooked steel fibres", Mater. Struct., 35(7), 434-442. https://doi.org/10.1007/BF02483148
  26. Romualdi, J.P. and Batson, G.B. (1963), "Mechanics of crack arrest in concrete", J. Eng. Mech., 89(EM3), 147-168.
  27. Saatci, S. and Vecchio, F.J. (2009), "Nonlinear finite element modelling of reinforced concrete structures under impact loads", ACI Struct. J., 106(5), 717-725.
  28. Trottier, J.F. and Banthia, N. (1994), "Toughness characterization of steel-fibre reinforced concrete", J. Mater. Civil Eng., 6(2), 264-289. https://doi.org/10.1061/(ASCE)0899-1561(1994)6:2(264)
  29. Xu, Z., Hao, H. and Li, H.N. (2012), "Dynamic tensile behaviour of fibre reinforced concrete with spiral fibres", Mater. Des., 42, 72-88. https://doi.org/10.1016/j.matdes.2012.05.047
  30. Zhang, X.X., Abd Elazim, A.M., Ruiz, G. and Yu, R.C. (2014), "Fracture behaviour of steel fibre-reinforced concrete at a wide range of loading rates", Int. J. Impact Eng., 71, 89-96. https://doi.org/10.1016/j.ijimpeng.2014.04.009
  31. Zienkiewicz, O.C. and Taylor, R.L. (2013), The Finite Element Method for Solid and Structural Mechanics, 7th Edition, Butterworth-Heinemann, Oxford, UK.
  32. Zisopoulos, P.M., Kotsovos, M.D. and Pavlovic, M.N. (2000), "Deformational behaviour of concrete specimens in uniaxial compression under different boundary conditions", Cement Concrete Res., 30(1), 153-159. https://doi.org/10.1016/S0008-8846(99)00227-6

피인용 문헌

  1. Experimental Investigation of Shear Strength for Steel Fibre Reinforced Concrete Beams vol.15, pp.1, 2018, https://doi.org/10.2174/1874836802115010081