DOI QR코드

DOI QR Code

Evaluation of moment amplification factors for RCMRFs designed based on Iranian national building code

  • Habibi, Alireza (Department of Civil Engineering, Shahed University) ;
  • Izadpanah, Mehdi (Department of Civil Engineering, Kermanshah University of Technology) ;
  • Rohani, Sina (Department of Civil Engineering, University of Kurdistan)
  • 투고 : 2019.08.04
  • 심사 : 2019.10.05
  • 발행 : 2020.01.25

초록

Geometric nonlinearity can significantly affect load-carrying capacity of slender columns. Dependence of structural stability on columns necessitates the consideration of second-order effects in the design process of columns, appropriately. On the whole, the design codes present a simplified procedure for second order analysis of slender columns. In this approximate method, the end moments of columns resulted from linear analysis (first-order) are multiplied by the recommended moment amplification factors of codes to achieve magnified moments of the second-order analysis. In the other approach, the equilibrium equations are directly solved for the deformed configuration of structure, so the resulting moments and deflections contain the influence of slenderness and increase more rapidly than do loads. The aim of this study is to evaluate the accuracy of moment amplification factors of Iranian national building code whose provisions are similar to the ACI requirement. Herein, finite element method is used to achieve magnified end moments of reinforced concrete moment resisting frames, and the outcomes are compared with the moments acquired based on the proposed approximate method by Iranian national building code. The results show that the approximate method of Iranian code for calculating magnified moments has significant errors for both unbraced and braced columns.

키워드

참고문헌

  1. ACI Committee and International Organization for Standardization (2008), Building Code Requirements for Structural Concrete (ACI 318-08) and Commentary, American Concrete Institute.
  2. American Concrete Institute (2014), Building Code Requirements for Structural Concrete (ACI 318-14): Commentary on Building Code Requirements for Structural Concrete (ACI 318R-14), An ACI Report, American Concrete Institute, ACI.
  3. Areiza-Hurtado, M. and Aristizabal-Ochoa, J.D. (2019), "Second-order analysis of a beam-column on elastic foundation partially restrained axially with initial deflections and semirigid connections", Struct., 20, 134-146. https://doi.org/10.1016/j.istruc.2019.03.010.
  4. Barros, H., Silva, V.D. and Ferreira, C. (2010), "Second order effects in slender concrete columns-reformulation of the Eurocode 2 method based on nominal curvature", Eng. Struct., 32(12), 3989-3993. https://doi.org/10.1016/j.engstruct.2010.08.005.
  5. BHRC (2015), Iranian Code of Practice for Seismic Resistant Design of Buildings: Standard No. 2800, 4th Edition, Building and Housing Research Center.
  6. Bonet, J.L., Romero, M.L. and Miguel, P.F. (2011), "Effective flexural stiffness of slender reinforced concrete columns under axial forces and biaxial bending", Eng. Struct., 33(3), 881-893. https://doi.org/10.1016/j.engstruct.2010.12.009.
  7. BSI. Eurocode 4 (2005), Design of Composite Steel and Concrete Structures_Part 1.1: General Rules and Rules for Buildings, BS EN 1994-1-1, London, BSI.
  8. Choi, D.H. and Yoo, H. (2009), "Iterative system buckling analysis, considering a fictitious axial force to determine effective length factors for multi-story frames", Eng. Struct., 31(2), 560-570. https://doi.org/10.1016/j.engstruct.2008.10.008.
  9. de Araujo, J.M. (2017), "Comparative study of the simplified methods of Eurocode 2 for second order analysis of slender reinforced concrete columns", J. Build. Eng., 14, 55-60. https://doi.org/10.1016/j.jobe.2017.10.003.
  10. Du, Z.L., Liu, Y.P. and Chan, S.L. (2017), "A second-order flexibility-based beam-column element with member imperfection", Eng. Struct., 143, 410-426. https://doi.org/10.1016/j.engstruct.2017.04.023.
  11. European Committee for Standardization (2004), Eurocode 2: Design of Concrete Structures - Part 1-1: General Rules and Rules for Buildings, EN 1992-1-1:2004, Brussels, Belgium.
  12. Fong, M., Liu, Y.P. and Chan, S.L. (2010), "Second-order analysis and design of imperfect composite beam-columns", Eng. Struct., 32(6), 1681-1690. https://doi.org/10.1016/j.engstruct.2010.02.016.
  13. Gil-Martin, L.M., Hernandez-Montes, E. and Aschheim, M. (2006), "Optimal design of planar frames based on stability criterion using first-order analysis", Eng. Struct., 28(13), 1780-1786. https://doi.org/10.1016/j.engstruct.2006.03.007.
  14. Habibi, A. and Bidmeshki, S. (2018), "A dual approach to perform geometrically nonlinear analysis of plane truss structures", Steel Compos. Struct., 27(1), 13-25. https://doi.org/10.12989/scs.2018.27.1.013.
  15. Habibi, A. and Bidmeshki, S. (2019), "An optimized approach for tracing pre-and post-buckling equilibrium paths of dpace yrusses", Int. J. Struct. Stab. Dyn., 19(4), 1950040. https://doi.org/10.1142/S0219455419500408.
  16. Hellesland, J. (2009), "Second order approximate analysis of unbraced multistorey frames with single curvature regions", Eng. Struct., 31(8), 1734-1744. https://doi.org/10.1016/j.engstruct.2009.02.015.
  17. Iu, C.K. (2015), "Generalised element load method for first-and second-order element solutions with element load effect", Eng. Struct., 92, 101-111. https://doi.org/10.1016/j.engstruct.2015.03.016.
  18. Izadpanah, M. and Habibi, A.R. (2018), "New spread plasticity model for reinforced concrete structural elements accounting for both gravity and lateral load effects", J. Struct. Eng., 144(5), 04018028. https://doi.org/10.1061/(ASCE)ST.1943-541X.0002016.
  19. Karaca, Z. and Turkeli, E. (2014), "The slenderness effect on wind response of industrial reinforced concrete chimneys", Wind Struct., 18(3), 281-294. http://dx.doi.org/10.12989/was.2014.18.3.281.
  20. Leite, L., Bonet, J.L., Pallares, L., Miguel, P.F. and Fernandez-Prada, M.A. (2013), "Experimental research on high strength concrete slender columns subjected to compression and uniaxial bending with unequal eccentricities at the ends", Eng. Struct., 48, 220-232. https://doi.org/10.1016/j.engstruct.2012.07.039.
  21. Oveisi, A., Nestorovic, T. and Nguyen, N.L. (2017), "Semi-analytical modeling and vibration control of a geometrically nonlinear plate", Int. J. Struct. Stab. Dyn., 17(4), 1771003. https://doi.org/10.1142/S0219455417710031.
  22. Rohani, S. (2016), "Evaluation of moment amplification factors for reinforced concrete moment resisting frames designed based on Iranian national building code", University of Kurdistan, Iran.
  23. The Ninth Issue of the National Building Regulations (2013), "Design and implementation of reinforced concrete buildings", Office of National Building Regulations.
  24. Thombare, C.N., Sangle, K.K. and Mohitkar, V.M. (2016), "Nonlinear buckling analysis of 2-D cold-formed steel simple cross-aisle storage rack frames", J. Build. Eng., 7, 12-22. https://doi.org/10.1016/j.jobe.2016.05.004.
  25. Vetr, M.G., Ghamari, A. and Bouwkamp, J. (2017), "Investigating the nonlinear behavior of Eccentrically Braced Frame with vertical shear links (V-EBF)", J. Build. Eng., 10, 47-59. https://doi.org/10.1016/j.jobe.2017.02.002.
  26. Wan, C.Y. and Zha, X.X. (2016), "Nonlinear analysis and design of concrete-filled dual steel tubular columns under axial loading", Steel Compos. Struct., 20(3), 571-597. https://doi.org/10.12989/scs.2016.20.3.571.
  27. Zubydan, A.H. (2010), "A simplified model for inelastic second order analysis of planar frames", Eng. Struct., 32(10), 3258-3268. https://doi.org/10.1016/j.engstruct.2010.06.015.

피인용 문헌

  1. A new procedure for post-buckling analysis of plane trusses using genetic algorithm vol.40, pp.6, 2020, https://doi.org/10.12989/scs.2021.40.6.817