Browse > Article
http://dx.doi.org/10.5000/EESK.2010.14.6.067

Verification of the Torsional Amplification Factor for the Seismic Design of Torsionally Imbalanced Buildings  

Lee, Kwang-Ho (인하대학교 건축학부)
Jeong, Seoung-Hoon (인하대학교 건축학부)
Publication Information
Journal of the Earthquake Engineering Society of Korea / v.14, no.6, 2010 , pp. 67-74 More about this Journal
Abstract
Because of the difference between the actual and computed eccentricity of buildings, symmetrical buildings will be affected by torsion. In provisions, accidental eccentricity is intended to cover the effect of several factors, such as unfavorable distributions of dead- and live-load masses and the rotational component of ground motion about a vertical axis. The torsional amplification factor is introduced to reduce the vulnerability of torsionally imbalanced buildings. The effect of the torsional amplification factor is observed for a symmetric rectangular building with various aspect ratios, where the seismic-force-resisting elements are positioned at a variable distance from the geometrical center in each direction. For verifying the torsional amplification factor in provisions, nonlinear reinforced concrete models with various eccentricities and aspect ratios are used in rock. The difference between the maximum displacements of the flexible edge obtained between using nonlinear static and time-history analysis is very small but the difference between the maximum torsional angles is large.
Keywords
Torsional imbalanced buildings; Torsional amplification factor; Accidental eccentricity; Earthquake response;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Federal Emergency Management Agency, NEHRP recommended provisions : Design examples, Report FEMA 451, Washington D.C., 3-22, 2006.
2 Chandler, A. M., and Hutchinson, G. L., "Evaluation of code torsional provisions by a time history approach," Earthquake Engineering and Structural Dynamics, Vol. 15, No. 4, 491-516, 1987.   DOI
3 Stefano, M. D., and Rutenberg, A., "A comparison of the present SEAOC/UBC torsional provisions with the old ones," Engineering Structures, Vol. 19, No. 8, 655-664, 1997.   DOI   ScienceOn
4 Structural Engineers Association of California, Recommended lateral force requirements and commentary, San Francisco, 13; 112; 121, 1999.
5 Federal Emergency Management Agency, NEHRP recommended Seismic provisions for new buildings and other structures, Report FEMA P-750, Washington D.C., 130, 2009.
6 ASCE/SEI 7-05, Minimum Design Loads for Buildings and Other Structures, American Society of Civil Engineers, 214; 130, 2006.
7 Federal Emergency Management Agency, NEHRP guidelines for the seismic rehabilitation of buildings, Report FEMA 273, Washington D.C., 3-2, 1997.
8 Federal Emergency Management Agency, Prestandard and commentary for the seismic rehabilitation of buildings, Report FEMA 356, Washington D.C., 3-3, 2000.
9 Federal Emergency Management Agency, NEHRP recommended provisions for seismic regulations for new buildings and other structures, Report FEMA 302, Washington D.C., 66, 1997.
10 Federal Emergency Management Agency, NEHRP recommended provisions for seismic regulations for new buildings and other structures, Report FEMA 368, Washington D.C., 76, 2000.
11 Federal Emergency Management Agency, NEHRP recommended provisions for seismic regulations for new buildings and other structures, Report FEMA 450, Washington D.C., 90, 2003.
12 Elnashai AS, Papanikolaou, V. and Lee, D.H., ZEUS-NL User Manual, University of Illinois at Urbana-Champaign /Mid-America Earthquake Center, 2002.
13 Duan, X. N., and Chandler, A. M., "Torsional coupling effects in the inelastic seismic response of structures in Europe," Proceedings of 9th european conference earthquake engineering, Moscow, I, 162-171, 1990.
14 Tso, W. K., and Ying, H., "Additional seismic inelastic deformation caused by structural asymmetry," Earthquake Engineering and Structural Dynamics, Vol. 19, No. 2, 243-258, 1990.   DOI
15 Chandler, A. M., and Duan, X. N., "Evaluation of factors influencing the inelastic seismic performance of torsionally asymmetric buildings," Earthquake Engineering and Structural Dynamics, Vol. 20, No. 8, 87-95, 1991.   DOI
16 De la Llera, J. C., and Chopra, A. K., Accidental and natural torsion in earthquake response and design of buildings, Report No. UCB/EERC-94/07, Earthquake engineering research center, University of California at Berkeley, 21; 63, 1994.
17 De la Llera, J. C., and Chopra, A. K., "Accidental torsion in buildings due to stiffness uncertainty," Earthquake Engineering and Structural Dynamics, Vol. 23, No. 2, 117-136, 1994.   DOI   ScienceOn
18 De la Llera, J. C., and Chopra, A. K., "Accidental torsion in buildings due to base rotational excitation," Earthquake Engineering and Structural Dynamics, Vol. 23, No. 9, 1003-1021, 1994.   DOI   ScienceOn
19 Tso, W. K., and Dempsey, K. M., "Seismic torsion provision for dynamic eccentricity," Earthquake Engineering and Structural Dynamics, Vol. 8, No. 3, 275-289, 1980.   DOI   ScienceOn
20 Rosenblueth, E., and Elorduy, J., "Response of linear systems to certain transient disturbances," Proceeding of fourth world conference on earthquake engineering, Santiago, Chile, A1-185-A1-196, 1969.
21 Dempsey, K. M., and Tso, W. K., "An alternative path to seismic torsional provision," Soil Dynamics and Earthquake Engineering, Vol. 1, No. 1, 3-10, 1982.
22 Federal Emergency Management Agency, NEHRP recommended provisions for seismic regulations for new buildings and other structures : Part 2 Commentary, Report FEMA 303, Washington D.C., 98, 1997.
23 British Standards Institution, Eurocode 8 : Design of Structures for Earthquake Resistance-Park 1: General rules, seismic actions and rules for buildings, EN 1998-1:2004, BSI, London, 54, 2004.
24 대한건축학회, 건축구조설계기준 및 해설, 대한건축학회, 121, 2006.
25 International conference of Building Officials, Uniform Building Code 1697 Edition, Pasadena, p124, 1967.
26 대한건축학회, 건축구조설계기준, 대한건축학회, 106, 2009.
27 Structural Engineers Association of California, Recommended lateral force requirements and commentary, San Francisco, 15; 38; 68-69, 1967.
28 Newmark, N. M., "Torsion in symmetrical buildings," Proceeding of fourth world conference on earthquake engineering, Santiago, Chile, A3-19-A3-32, 1969.
29 Newmark, N. M., and Rosenblueth, E., Fundamental of earthquake engineering, Prentice-Hall, 495, 1971