Assessment of Seismic Non-linear Behavior of Hill-Type Topographies Subjected to propagating SV Waves

Document Type : Articles

Authors

Department of Civil Engineering, Zanjan Branch, Islamic Azad University, Zanjan, Iran

Abstract

IntroductionGenerally, topographic effects are mostly introduced by hills, canyons, basins, and slopes. Besides, the topographic features produce significant seismic site-effects and can apply a crucial influence on the severity of building damages and its spatial distribution during earthquakes. Some experience observation such as Tarzana hill in the 1994 Northridge earthquake and the Kushiro Meteorological Observatory in the 1993 Kushiro-Oki earthquake, revealed the effective role of surface topographies such as hilland ridges on the seismic damage on the crest and hillsides. Reviewing the technical literature can deduce that the most studies about the effects of topography and the amplification patterns are limited to the linear behavior of the medium.However, theuse of linear models to estimate amplification patterns of waves can lead tomisleading resultsthanthe actual behavior ofthe soil, especially in the soft soils. The non-linear seismic behavior of the hill topographic features unknown in comparison withother types of topographic irregularities, e.g. basins or alluvial valleys. Hence, in this study, the effects of non-linear behavior of the hilltypeof topographies due to propagating SV waves using ABAQUS program in the form of parametric studies are discussed.In this regard, the trapezoidal-shaped hill has been taken into account for parametric study with four shape ratio (SR=0.1, 0.3, 0.5 and 0.7). Besides, in order to evaluate the effect of topography geometry, the semi-sine and semi-elliptical shapes of the hills have been studied. The constitutive model used herein is based on non-linear Kinematic Hardening model with Von-Mises failure criterion.Parametric StudiesIn this research, the finite element method (ABAQUS software) is used to evaluate the hill-typeTopographiesbehavior due to the vertically in-plane propagating incident SV waves. The hill-typeTopographieshas been excited vertically by Ricker-type pulse excitations. In this regard, two center frequencies (fp) of low (i.e. 1.4 Hz) and high (i.e. 4.3 Hz) have been considered to cover all frequency responses with a maximum acceleration equal to 0.3 g. The constitutive model used herein is based on non-linear Kinematic Hardening model, which is suitable for claymaterials. The results are presented as horizontal component amplifications (direct component) or vertical (indirect component).Spectral amplifications have been defined with respect to the free-fieldmotion, based on the maximum Fourier amplitude of the horizontal or vertical component, to the maximum Fourier amplitude of the Free-field motion. In this research, the horizontal and vertical component amplifications are shown, with AHand AVabbreviations, respectively. Moreover, the obtained results provided for the dimensionless distance (X/L) in which X is points from the center of the hill and L is half the width of the hill. All results have been compared in two linear and non-linear soil behaviors.Concluding RemarksThe obtainedresults indicated that considering the non-linear soil behavior can reduce seismic response of topographic effects in comparison with linear behavior. Furthermore, the maximum amplification appears on the crest of the hill in both linearandnon-linear behaviors.The non-linearamplification values reducedabout 15 percent at the lowerfrequencies for the trapezoidal-shaped hill with shape ratio (SR) of 0.7 compared with linear behavior. The seismic response of topographic irregularities tends towards free-field ground motion with far from surrounding hills. Besides, in this research the PGA values versus depth and the impedance ratio between inside of hill and its base materials have been studied. The results of this research can be used in seismic hazard and microzonation studies of various urban areas and to point out this the hills with softer materials than the bed, where soil behavior can be non-linearand usinglinear models, can lead tomisleading resultsthanthe actual behavior ofthe soil.

Keywords

References

  1. Assimaki, D. and Jeong, S. (2013) Ground-motion observations at hotel Montana during the M 7.0 2010 Haiti earthquake: Topography or Soil Amplification? Bulletin of the Seismological Society of America, 103(5).
  2. Bouchon, M. and Barker, J. (1996) Seismic response of a hill: The example of Tarzana, California. Bulletin of the Seismological Society of America, 86(1A), 66–72.
  3. Bouchon, M. (1973) Effect of topography on surface motion. Bulletin of the Seismological Society of America, 63.
  4. Sanchez-Sesma, F.J. (1987) Site effects on strong ground motion. Soil Dyn. Earthquake Eng., 6, 124-132.
  5. Moczo, P., Bystricky, E., Kristek, J., Carcione, J.M., and Bouchon, M. (1997) Hybrid modeling of P-SV seismic motion at inhomogenous viscoelastic topographic structures. Bulletin of the Seismological Society of America, 87, 1305-1323.
  6. Bouckovala, G., Papadimitriou, D., Achilleas, G. (2005) Numerical evaluation of slope topography effects on seismic ground motion. Soil Dynamics and Earthquake Engineering, 25,547-558.
  7. Kamalian, M., Jafari, M., Sohrabi-bidar, A., Razmkhah, A. (2007) Seismic response of 2-D trapezoidal shaped hills to vertically propagating incident waves. Fani Mohandesi Modarres, No. 29 (in Persian).
  8. Kamalian, M. Jafari, M. Sohrabi-bidar, A. Razmkhah, A. (2008) Seismic response of 2-D semi-sine shaped hills to vertically propagating incident waves: Amplification patterns and engineering applications. Earthquake Spectra, 24(2), 405-430.
  9. Razmkhah, A., Kamalian, M., and Alielahi, H. (2008) Seismic behavior of 2D topographic features subjected to vertically propagating incident SV at high frequency. Proc. of the 4th Decennial Geotechnical Earthquake Engineering and Soil Dynamics Conference (GEESD 5), EESD Committee of ASCE’s Geo-Institute.
  10. Psarropoulos, P.N., Tazoh, T., Gazetas, G., Apostolou, M. (2007) Linear and nonlinear valley amplification effects on seismic ground motion. Soil and Foundation, 47(5), 857-871.
  11. Gelagoti, F., Kourkoulis, R., Anastasopoulis, I. Tazoh, T and Gazetas, G. (2010) Seismic wave propagation in a very soft alluvial valley: Sensitivity to ground-motion details and soil nonlinearity, and generation of a parasitic vertical component. Bulletin of the Seismological Society of America, 100(6), 3035-3054.
  12. Gelagoti, F., Kourkoulis, R., Anastasopoulis, and Gazetas, G. (2012) Nonlinear dimensional analysis of trapezoidal valleys subjected to vertically propagating SV wave. Bulletin of the Seismological Society of America, 102(3), 999-1017.
  13. Amelsakhi, M., Sohrabi-Bidar, A., Sharegi, A. (2014) Spectral assessing of topographic effects on seismic behavior of trapezoidal hill. International Journal of Environment, Earth Sciense and Engineering, 8(4).
  14. Armstrong, P.J., and Frederick, C.O. (1966) A mathematical representation of the multiaxial bauschinger effect. CEGB Rep. No. RD/B/N 731.
  15. Lemaitre, J. and Chaboche, J.L. (1990) Mechanics of Solid Materials. Cambridge Univ. Press, Cambridge, UK.
  16. Anastasopoulous, I., Gelagoti, F., Kourkoulis, R., and Gazetas, G., ASCE, M. (2011) Simplified constitutive model for simulation of cyclic response of shallow foundations: Validation against laboratory test. Geotechnical and Geoenvironmental Engineering, 137(12), 1154-1168.
  17. Ziegler, H. (1959) A modification of Prager’s hardening rule. Quart. Appl. Math., 17, 55–65.
  18. Gerolymos, N., Gazetas, G., and Tazoh, T. (2005) Seismic response of yielding pile in non-linear soil. Proc. 1st Greece-Japan Workshop, Seismic Design, Observation, and Retrofit of Foundations, National Technical Univ. of Athens, Athens, Greece, 25–36.
  19. CEN Eurocode 8 (EC8) (2006) Design of Structures for Earthquake Resistance. EN 1998–5. European Committee for Standardization, Brussels.
  20. Kulhawy, F.H. and Mayne, P.W. (1990) Manual on Estimating Soil Properties for Foundation Design. Cornell University, Geotechnical Engineering Group, Hollister Hall Ithaca (EL-6800), New York 14853-3501.
  21. Jin, D.D., Chen, J.X., and Dong, F.F. (2014) Seismic Response of a Real Basin Site Considering Topography Effect and Nonlinear Characteristic of Soil. International Effort in Lifeline Earthquake Engineering.

Files

History

  • Receive Date: 14 June 2017
  • Revise Date: 25 February 2021
  • Accept Date: 26 December 2020

Share

How to cite

Statistics