Dependence of Damping Correction Factors for Response Spectra on Duration and Numbers of Cycles
Publication: Journal of Structural Engineering
Volume 134, Issue 8
Abstract
Many modern applications in earthquake engineering require the use of pseudoacceleration response spectra or relative displacement response spectra calculated for damping ratios other than the commonly assumed 5% of critical. The simplest way to obtain such spectra is to derive ratios of the spectral ordinates at the desired damping ratio to the 5% damped spectrum, which can then be applied as scaling factors. These scaling factors have previously been shown to be mildly dependent upon period as well as strongly dependent upon duration. In this paper, the dependence of the scaling factors with respect to both duration and the number of equivalent load cycles is quantified. Generic equations are derived that may be used to estimate the spectral response over a wide range of damping ratios as a function of significant duration (both and ), and number of cycles . While the dependence upon these predictor variables is clear, the derived relationships cannot be directly incorporated into design codes due to the fact that strong ground-motion duration and number of equivalent cycles are generally not specified as part of seismic design actions.
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Acknowledgments
The writers are indebted to Jon Hancock for providing the code for calculating the spectra, durations, and numbers of cycles employed in this study and to John Alarcón for providing the calculated durations and numbers of cycles.
References
Akkar, S., and Bommer, J. J. (2007). “Prediction of elastic displacement response spectra in Europe and the Middle East.” Earthquake Eng. Struct. Dyn., 36(10), 1275–1301.
Ashour, S. A. (1987). “Elastic seismic response of buildings with supplemental damping.” Univ. of Michigan, Ann Arbor, Mich.
Atkinson, G. M., and Pierre, J. R. (2004). “Ground-motion response spectra in Eastern North America for different critical damping values.” Seismol. Res. Lett., 75(4), 541–545.
Bommer, J. J., Elnashai, A. S., and Weir, A. G. (2000). “Compatible acceleration and displacement spectra for seismic design codes.” Proc., 12th World Conf. on Earthquake Engineering, Auckland, New Zealand, New Zealand Society for Earthquake Engineering, Inc., Wellington, New Zealand, Paper No. 207.
Bommer, J. J., and Martínez-Pereira, A. (1999). “The effective duration of earthquake strong motion.” J. Earthquake Eng., 3(2), 127–172.
Bommer, J. J., and Mendis, R. (2005). “Scaling of spectral displacement ordinates with damping ratios.” Earthquake Eng. Struct. Dyn., 34(2), 145–165.
Bommer, J. J., and Pinho, R. (2006). “Adapting earthquake actions in Eurocode 8 for performance-based seismic design.” Earthquake Eng. Struct. Dyn., 35(1), 39–55.
Bommer, J. J., Stafford, P. J., Alarcón, J. E., and Akkar, S. (2007). “The influence of magnitude range on empirical ground-motion prediction.” Bull. Seismol. Soc. Am., 97(6), 2152–2170.
Building Seismic Safety Council (BSSC). (2004). “NEHRP recommended provisions for seismic regulations for new buildings and other structures.” National Institute of Buildings Sciences, Washington, D.C.
Cameron, W. I., and Green, R. U. (2007). “Damping correction factors for horizontal ground-motion response spectra.” Bull. Seismol. Soc. Am., 97(3), 934–960.
Campbell, K. W., and Bozorgnia, Y. (2003). “Updated near-source ground-motion (attenuation) relations for the horizontal and vertical components of peak ground acceleration and acceleration response spectra.” Bull. Seismol. Soc. Am., 93(1), 314–331.
CEN. (2004). “Eurocode 8, design of structures for earthquake resistance—Part 1: General rules, seismic actions, and rules for buildings.” EN 1998-1:2004, Comité Européen de Normalisation, Brussels, Belgium.
Chopra, A. K. (2007). Dynamics of structures, theory and applications to earthquake engineering, 3rd Ed., Pearson Prentice-Hall, Upper Saddle River, N.J.
Douglas, J. (2003). “Earthquake ground motion estimation using strong-motion records: A review of equations for the estimation of peak ground acceleration and response spectral ordinates.” Earth-Sci. Rev., 61(1–2), 43–104.
Hancock, J., and Bommer, J. J. (2005). “The effective number of cycles of earthquake ground motion.” Earthquake Eng. Struct. Dyn., 34(6), 637–664.
Hancock, J., and Bommer, J. J. (2006). “A state-of-knowledge review of the influence of strong-motion duration on structural damage.” Earthquake Spectra, 22(3), 827–845.
Lin, Y. Y., and Chang, K. C. (2003). “Study on damping reduction factors for buildings under earthquake ground motions.” J. Struct. Eng., 129(2), 206–214.
Lin, Y. Y., and Chang, K. C. (2004). “Effects of site classes on damping reduction factors.” J. Struct. Eng., 130(11), 1667–1675.
Lin, Y. Y., Miranda, E., and Chang, K. C. (2005). “Evaluation of damping reduction factors for estimating elastic response of structures with high damping.” Earthquake Eng. Struct. Dyn., 34(11), 1427–1443.
Malhotra, P. K. (2006). “Smooth spectra of horizontal and vertical ground motions.” Bull. Seismol. Soc. Am., 96(2), 506–518.
Mendis, R., and Bommer, J. J. (2006). “Modification of the Eurocode 8 damping reduction factors for displacement spectra.” Proc., 1st European Conf. on Earthquake Engineering and Seismology, San Francisco, Earthquake Engineering Research Institute (EERI), Oakland, Calif., Paper No. 1203.
NEHRP. (2000). “Recommended provisions for seismic regulations for new buildings.” Federal Emergency Management Agency, Washington, D.C.
Newmark, N. M., and Hall, W. J. (1982). Earthquake spectra and design, Earthquake Engineering Research Institute, Berkeley, Calif.
Nielsen, A. A. (2007). “Least squares adjustment: Linear and nonlinear weighted regression analysis.” Danish National Space Center/Informatics and mathematical modelling, Technical Univ. of Denmark, Lyngby, Denmark, http://www2.imm.dtu.dk/pubdb/p.php?2804 (March 2, 2007 ).
Nigam, N. C., and Jennings, P. C. (1969). “Calculation of response spectra from strong-motion earthquake records.” Bull. Seismol. Soc. Am., 59(2), 909–922.
Power, M., Chiou, B., Abrahamson, N. A., and Roblee, C. (2006). “The ‘Next generation of ground motion attenuation models’ (NGA) project: An overview.” Proc., 8th U.S. National Conf. on Earthquake Engineering, San Francisco, Earthquake Engineering Research Institute (EERI), Oakland, Calif., Paper No. 2022.
Ramirez, O. M., et al. (2000). “Development and evaluation of simplified procedures for analysis and design of buildings with passive energy dissipation systems.” Multidisciplinary Center for Earthquake Engineering Research, Univ. at Buffalo, State University of New York, Buffalo, N.Y.
Wu, J., and Hanson, R. D. (1989). “Study of inelastic spectra with high damping.” J. Struct. Eng., 115(6), 1412–1431.
Youngs, R. R., Abrahamson, N. A., Makdisi, F. I., and Sadigh, K. (1995). “Magnitude-dependent variance of peak ground acceleration.” Bull. Seismol. Soc. Am., 85(4), 1161–1176.
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© 2008 ASCE.
History
Received: Mar 14, 2007
Accepted: Jul 31, 2007
Published online: Aug 1, 2008
Published in print: Aug 2008
Notes
Note. Associate Editor: Rakesh K. Goel
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