Earthquakes and Structures

  • 제1권2호
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  • Pages.163-175
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  • 2010
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  • 2092-7614(pISSN)
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  • 2092-7622(eISSN)
테크노프레스 (Techno-Press)
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DOI QR코드

DOI QR Code

Modal rigidity center: it's use for assessing elastic torsion in asymmetric buildings

  • Georgoussis, George K. (Department of Civil and Construction Engineering, School of Pedagogical and Technological Education (ASPETE))
  • 투고 : 2009.12.11
  • 심사 : 2010.03.24
  • 발행 : 2010.06.25
⟨ 이전 논문 다음 논문 ⟩

초록

The vertical axis through the modal center of rigidity (m-CR) is used for interpreting the code torsional provisions in the design of eccentric multi-story building structures. The concept of m-CR has been demonstrated by the author in an earlier paper and the particular feature of this point is that when the vertical line of the centers of mass at the floor levels is passing through m-CR, minimum base torsion is developed. For this reason the aforesaid axis is used as reference axis for implementing the code provisions required by the equivalent static analysis. The study examines uniform mixed-bent-type multistory buildings with simple eccentricity, ranging from torsionally stiff to torsionally flexible systems. Using the results of a dynamic response spectrum analysis as a basis for comparisons, it is shown that the results of the code static design are on the safe side in torsionally stiff buildings, but unable to predict the required strength of bents on the stiff side of systems with a predominantly torsional response. Suggestions are made for improving the code provisions in such cases.

키워드

참고문헌

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  4. Design Principles for Minimum Torsional Response of Wall-Frame Concrete Structures 2017, https://doi.org/10.1080/13632469.2017.1360222
  5. Preliminary Structural Design of Wall-Frame Systems for Optimum Torsional Response vol.11, pp.1, 2017, https://doi.org/10.1007/s40069-016-0183-2
  6. The use of Modal Rigidity Center for Assessing Code Provisions in Asymmetric Buildings vol.14, 2011, https://doi.org/10.1016/j.proeng.2011.07.158
  7. Centres of rigidity in multi-storey asymmetric diaphragm systems for general lateral static loading vol.150, 2017, https://doi.org/10.1016/j.engstruct.2017.06.072
  8. Minimizing the torsional response of inelastic multistory buildings with simple eccentricity vol.42, pp.11, 2015, https://doi.org/10.1139/cjce-2015-0091
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  11. Seismic Behavior of Horizontally Irregular Structures: Current Wisdom and Challenges Ahead vol.68, pp.6, 2016, https://doi.org/10.1115/1.4034725
  12. Locating optimum torsion axis in asymmetric buildings subjected to seismic excitation vol.171, pp.9, 2018, https://doi.org/10.1680/jstbu.17.00068
  13. Accounting for Torsional Response in Direct Displacement-based Design of Plan-asymmetric Reinforced Concrete Frame Buildings vol.23, pp.3, 2019, https://doi.org/10.1007/s12205-019-1739-x
  14. Dynamic eccentricities and the “capable near collapse centre of stiffness” of reinforced concrete single-storey buildings in pushover analysis vol.166, pp.None, 2010, https://doi.org/10.1016/j.engstruct.2018.03.056
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  16. The effect of accidental eccentricities on the inelastic torsional response of buildings vol.75, pp.2, 2010, https://doi.org/10.12989/sem.2020.75.2.145
  17. Mitigating mass eccentricity effects on the rotational response of setbacks structures: An analytical solution for linear systems vol.28, pp.None, 2010, https://doi.org/10.1016/j.istruc.2020.09.062
  18. Conditions of structural irregularity. Relationships with observed earthquake damage in Mexico City in 2017 vol.143, pp.None, 2010, https://doi.org/10.1016/j.soildyn.2021.106630