The two- and three-dimensional response spectra: Orientation-independent intensity measures more suitable for seismic structural design

Abstract

This paper presents two physics-based, orientation-independent intensity measures that truly captures the three-dimensional motion of an orthogonal array of accelerometers and are more appropriate for seismic structural design. This is achieved by processing all three components of the record simultaneously, rather than simply combining the results of processing each component in isolation. Compared to other commonly accepted orientation-independent intensity measures, it was found that horizontal seismic demand may be systematically underestimated by as much as 29% in the worst-case scenario. In addition, these new measures are much more computationally efficient than the current ones, as they reduce the number of response spectra calculations per seismic record to just 2 or 3, depending on the measure. Thus, the orientation-independent intensity measures introduced here optimize the processing of seismic records and may help to reduce the uncertainty of the estimation of the seismic acceleration for structural design.

Keywords

ground motion / intensity measure / response spectra / signal processing

References

[1] López OA, Hernández JJ, Bonilla R, Fernández A. Response spectra for multicomponent structural analysis. Earthquake Spectra. 2006;22(1):85-113.

[2] Penzien J, Watabe M. Characteristics of 3-dimensional earthquake ground motions. Earthq Eng Struct Dyn. 1975;3:365-373.

[3] Beyer K, Bommer JJ. Relationships between median values and between aleatory variabilities for different definitions of the horizontal component of motion. Bull Seismol Soc Am. 2006;96(4A):1512-1522.

[4] Hong HP, Goda K. Characteristics of horizontal ground motion measures along principal directions. Earthq Eng Eng Vibr. 2010;9(1):9-22.

[5] Dai Z, Li X, Hou C. Orientation-independent measures of ground motion made easy. Bull Seismol Soc Am. 2014;104(3):1268-1275.

[6] Douglas J. 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. 2003;61(1-2):43-104.

[7] Boore DM, Watson-Lamprey J, Abrahamson NA. Orientation-Independent measures of ground motion. Bull Seismol Soc Am. 2006;96(4A):1502-1511.

[8] Boore DM. Orientation-independent, nongeometric-mean measures of seismic intensity from two horizontal components of motion. Bull Seismol Soc Am. 2010;100(4):1830-1835.

[9] Pinzón LA, Pujades LG, Hidalgo-Leiva DA, Díaz S. Directionality models from ground motions of Italy. Ingegneria Sismica. 2018;XXXV(3):43-62.

[10] Poulos A, Miranda E. Proposal of orientation-independent measure of intensity for earthquake-resistant design. Earthquake Spectra. 2022;38(1):235-253.

[11] Huang Y-N. Whittaker AS, Luco N. Maximum spectral demands in the near-fault region. Earthquake Spectra. 2008;24(1):319-341.

[12] Hidalgo-Leiva DA, Pujades LG, Díaz SA, Barbat AH, González-Drigo JR Orientation-independent measures of ground motion for a database of Central America. Proceedings of the 16th World Conference on Earthquake Engineering, Santiago, Chile, Chilean. Association of Seismology and Earthquake Engineering, ACHISINA 2017.

[13] Housner GW Intensity of Ground Motion During Strong Earthquakes. California Institute of Technology;(Unpublished) 1952.

[14] Nigam NC, Jennings PC. Digital Calculation of Response Spectra from Strong-Motion Earthquake Records. California Institute of Technology, Earthquake Engineering Research Laboratory;1968.

[15] BSSC. NEHRP Recommended Seismic Provisions for New Buildings and Other Structures. Building Seismic Safety Council;2009.

[16] Stewart JP, Abrahamson NA, Atkinson GM, et al. Representation of bidirectional ground motions for design spectra in building codes. Earthquake Spectra. 2011;27(3):927-937.

[17] RAII-UNAM. Base de datos de registros acelerográficos de la RAII-UNAM (in Spanish). [Online]. 2018. Accessed August 2023. http://aplicaciones.iingen.unam.mx/AcelerogramasRSM/

[18] PEER. New NGA-West 2 Ground Motion Database. [Online]. 2015. Accessed August 2023. https://peer.berkeley.edu/research/nga-west-2

[19] Campbell KW, Bozorgnia Y. NGA ground motion model for the geometric mean horizontal component of PGA, PGV, PGD and 5%damped linear elastic response spectra for periods ranging from 0.01 to 10 s. Earthquake Spectra. 2008;24(1):139-171.

[20] Watson-Lamprey JA, Boore DM Beyond SaGMRotI: conversion to SaArb, SaSN, and SaMaxRot. Bull Seismol Soc Am. 2007;97(5):1511-1524.

RIGHTS & PERMISSIONS

2024 Tianjlin University and John Wiley & Sons Australia, Ltd.