Seismic Amplification of Peak Ground Acceleration, Velocity, and Displacement by Two-Dimensional Hills

نوع مقاله : مقاله پژوهشی‌

نویسندگان

1 دانشکده زمین شناسی، پردیس علوم، دانشگاه تهران، تهران، ایران

2 گروه مهندسی عمران، دانشگاه صنعتی قم. قم، ایران

3 گروه مهندسی عمران، دانشگاه ارومیه، ارومیه، ایران

چکیده

There are valuable investigations on the amplification effects of the topography on the seismic response in the frequency domain; however, a question is that how one can estimate the amplification of time domain peak ground acceleration (PGA), peak ground velocity (PGV), and peak ground displacement (PGD) over the topographic structures. In this study, the numerical approach has been used for the evaluation of time domain peak ground motion parameters amplification on a two-dimensional Gaussian-shaped hill in a typical rocky medium. Five normalized geometries, as well as the twelve normalized vertical incident motions, have been used. Incident motions are SV wave of Ricker type. Time domain responses of displacements, velocities, and accelerations have been calculated and analyzed in selected points of the hills. Tabulated results illustrate a significant role of geometry on the patterns of the amplification, and that almost the top of the hill amplifies and the hill toe de-amplifies the motion. Meanwhile, the rate of the amplification and de-amplification generally depends on the predominant period of the incident motion. Comparison of the amplification of PGA, PGV, and PGD values with the Fourier amplification curves showed that, in general, there is a well-matched correlation between them; however, the time domain amplifications of PGA, PGV, and PGD values have a gentler variation with the predominant period of the motion. It seems that one can give a reliable estimation of time domain amplification of PGA, PGV, and PGD values by using averaged Fourier amplifications over the suitable range of frequencies around the predominant period of the input motion.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Seismic Amplification of Peak Ground Acceleration, Velocity, and Displacement by Two-Dimensional Hills

نویسندگان [English]

  • Abdollah Sohrabi-Bidar 1
  • Masoud Amel-Sakhi 2
  • Arash Shareghi 3
  • Shahram Maghami 1
1 School of Geology, College of the Sciences, University of Tehran, Tehran, Iran
2 Department of Civil Engineering, Qom University of Technology, Qom, Iran
3 Department of Civil Engineering, University of Urmia, Urmia, Iran
چکیده [English]

There are valuable investigations on the amplification effects of the topography on the seismic response in the frequency domain; however, a question is that how one can estimate the amplification of time domain peak ground acceleration (PGA), peak ground velocity (PGV), and peak ground displacement (PGD) over the topographic structures. In this study, the numerical approach has been used for the evaluation of time domain peak ground motion parameters amplification on a two-dimensional Gaussian-shaped hill in a typical rocky medium. Five normalized geometries, as well as the twelve normalized vertical incident motions, have been used. Incident motions are SV wave of Ricker type. Time domain responses of displacements, velocities, and accelerations have been calculated and analyzed in selected points of the hills. Tabulated results illustrate a significant role of geometry on the patterns of the amplification, and that almost the top of the hill amplifies and the hill toe de-amplifies the motion. Meanwhile, the rate of the amplification and de-amplification generally depends on the predominant period of the incident motion. Comparison of the amplification of PGA, PGV, and PGD values with the Fourier amplification curves showed that, in general, there is a well-matched correlation between them; however, the time domain amplifications of PGA, PGV, and PGD values have a gentler variation with the predominant period of the motion. It seems that one can give a reliable estimation of time domain amplification of PGA, PGV, and PGD values by using averaged Fourier amplifications over the suitable range of frequencies around the predominant period of the input motion.

کلیدواژه‌ها [English]

  • topographic effect
  • peak ground motion parameters
  • amplification
  • two-dimensional hills

مراجع

Ashford, S. A., Sitar, N., Lysmer, J., and Deng, N., 1997, Topographic effects on the seismic response of steep slopes: Bulletin of the Seismological Society of America, 87(3), 701-709.
Athanasopoulos, G., Pelekis, P., and Leonidou, E., 1999, Effects of surface topography on seismic ground response in the Egion (Greece) 15 June 1995 earthquak: Soil Dynamics and Earthquake Engineering, 18(2), 135-149.
Bard, P. Y., 1982, Diffracted waves and displacement field over two‐dimensional elevated topographies: Geophysical Journal of the Royal Astronomical Society, 71(3), 731-760.
Boore, D. M., 1972, A note on the effect of simple topography on seismic SH waves: Bulletin of the Seismological Society of America, 62(1), 275-284.
Boore, D. M., 1973, The effect of simple topography on seismic waves: Implications for the accelerations recorded at Pacoima dam, San Fernando Valley, California: Bulletin of the Seismological Society of America, 63(5), 1603-1609.
Bouchon, M., 1973, Effect of topography on surface motion: Bulletin of the Seismological Society of America, 63(2), 615-632.
Bouckovalas, G. D., and Kouretzis, G., 2001, Stiff soil amplification effects in the 7 September 1999 Athens (Greece) earthquake: Soil Dynamics and Earthquake Engineering, 21(8), 671-687.
Bouckovalas, G. D., and Papadimitriou, A. G., 2005, Numerical evaluation of slope topography effects on seismic ground motion: Soil Dynamics and Earthquake Engineering, 25(7), 547-558.
Building Standard Law of Japan (BSL), 2004, Building Research Institute, Tokyo, Japan.
Celebi, M., 1991, Topographical and geological amplification, case studies and engineering implications: Structural Safety, 10(1), 199-217.
Celebi, M., 1987, Topographical and geological amplifications determined from strong-motion and aftershock records of the 3 March 1985 Chile earthquake: Bulletin of the Seismological Society of America, 77(4), 1147-1167.
ITASCA, 2017, FLAC 3D (Fast Lagrangian Analysis of Continua): Itasca Consulting Group Inc., Minneapolis, Minnesota, USA.
Kamalian, M., Gatmiri, B., and Sohrabi-Bidar, A., 2003, On time-domain two-dimensional site response analysis of topographic structures by BEM: Journal of Seismology and Earthquake Engineering, 5(2), 35-45.
Kamalian, M., Jafari, M., Sohrabi-Bidar, A., Razmkhah, A., and Gatmiri, B., 2006, Time-domain two-dimensional site response analysis of non-homogeneous topographic structures by a hybrid BE/FE method: Soil Dynamics and Earthquake Engineering, 26(8), 753-765.
Kamalian, M., Sohrabi-Bidar, A., Razmkhah, A., Taghavi, A., and Rahmani, I., 2008, Considerations on seismic micro zonation in areas with two-dimensional hills: Journal of Earth System Science, 117(2), 783-796.
Kuhlemeyer, R. L., Lysmer, J., 1973, Finite element method accuracy for wave propagation problems: Journal of the Soil Mechanics and Foundations Division, 99 (Tech Rpt.).
Sánchez-Sesma, F. J., and Campillo, M., 1991, Diffraction of P, SV, and Rayleigh waves by topographic features: A boundary integral formulation: Bulletin of the Seismological Society of America, 81(6), 2234-2253.
Sánchez-Sesma, F. J., and Campillo, M., 1993, Topographic effects for incident P, SV and Rayleigh waves. Tectonophysics, 218(1), 113-125.
Sohrabi-Bidar, A., Kamalian, M., and Jafari, M., 2009a, Seismic waves scattering in three-dimensional homogeneous media using time-domain boundary element method: Journal of the Earth and Space Physics.
Sohrabi-Bidar, A., Kamalian, M., and Jafari, M., 2009b, Time‐domain BEM for three‐dimensional site response analysis of topographic structures: International Journal for Numerical Methods in Engineering, 79(12), 1467-1492.
Sohrabi-Bidar, A., Kamalian, M., and Jafari, M., 2010, Seismic response of 3‐D Gaussian‐shaped valleys to vertically propagating incident waves: Geophysical Journal International, 183(3), 1429-1442.
Solomos, G., Pinto, A., and Dimova, S., 2008, A review of the seismic hazard zonation in national building codes in the context of Eurocode 8, Support to the Implementation, Harmonization and Further Development of the Eurocodes: Italy, JRC European Commission; 3.
Spudich, P., Hellweg, M., and Lee, W., 1996, Directional topographic site response at tarzana observed in aftershocks of the 1994 Northridge, California, earthquake: implications for main-shock motions: Bulletin of the Seismological Society of America, 86(1B), S193-S208.
Trifunac, M. D., and Hudson, D. E., 1971, Analysis of the Pacoima dam accelerogram San-Fernando, California, earthquake of 1971: Bulletin of the Seismological Society of America, 61(5), 1393-1411.
Wang, F., Miyajima, M., Dahal, R., Timilsina, M., Li, T., Fujiu, M., Kuwada, Y., and Zhao, Q., 2016, Effects of topographic and geological features on building damage caused by 2015.4. 25 Mw 7.8 Gorkha earthquake in Nepal, a preliminary investigation report: Geoenvironmental Disasters, 3(1), 1-17.
Wong, H., 1982, Effect of surface topography on the diffraction of P, SV, and Rayleigh waves: Bulletin of the Seismological Society of America, 72(4), 1167-1183.
Zhang, B., Papageorgiou, A. S., and Tassoulas, J. L., 1998, A hybrid numerical technique, combining the finite-element and boundary-element methods, for modeling the 3D response of 2D scatterers: Bulletin of the Seismological Society of America, 88(4), 1036-1050.
مجله ژئوفیزیک ایران
دوره 12، شماره 5
1398
صفحه 68-81

فایل ها

هم رسانی

ارجاع به این مقاله

آمار