Advertisement

Pure and Applied Geophysics

, Volume 167, Issue 12, pp 1485–1510 | Cite as

Effects of Impedance Contrast and Soil Thickness on Basin-Transduced Rayleigh Waves and Associated Differential Ground Motion

  • J. P. Narayan
Article

Abstract

This paper presents the effects of impedance contrast (IC) across the basin edge, velocity contrast between the basin and underlying bedrock, Poisson’s ratio and soil thickness on the characteristics of basin-transduced Rayleigh (BTR) waves and associated differential ground motion (DGM). Analysis of simulated results for a two-dimensional (2D) basin revealed complex mode transformation of Rayleigh waves after entering the basin. Excellent correlation of frequencies corresponding to different spectral ratio peaks in ellipticity curves of BTR waves and spectral amplification peaks was obtained. However, such correlation was not observed between values of peaks in ellipticity curves and spectral amplification at the corresponding frequencies. An increase of spectral amplification with IC was obtained. The largest spectral amplification was more than twice the IC in the horizontal component and more than the IC in the vertical component in the case of large and same impedance contrast for P- and S-waves. It was concluded that the frequency corresponding to the largest spectral amplification was greater than the fundamental frequency of soil by around 14% and 44% in the vertical and horizontal components, respectively. Spectral amplification of the vertical component was negligible when soil thickness was less than around 15–20 times the S-wave wavelength in the basin. The largest values of peak ground displacement (PGD) and peak differential ground motion (PDGM) were obtained very near the basin edge, and their values with offset from the edge were strongly dependent on the IC across the basin edge, Poisson’s ratio, velocity contrast between the basin and underlying bedrock (dispersion), damping and soil thickness. The obtained value of PDGM for a span of 50 m in the horizontal and vertical components due to the BTR wave was of the order of 0.75 × 10−3 and 1.32 × 10−3 for unit amplitude (1.0 cm) in the horizontal component of the Rayleigh wave at rock very near the basin edge.

Keywords

Basin-transduced surface wave complex mode transformation spectral amplification of surface waves differential ground motion 2D finite-difference simulation 

Notes

Acknowledgments

The author is grateful to Dr. Ivo Oprsal and Dr. Emmanuel Chaljub for valuable comments and suggestions, which led to great improvements in the original manuscript, and also to the Earthquake Risk Evaluation Centre (EREC), IMD, New Delhi for financial assistance through grant ERC-244-EQD.

References

  1. Bard, P.-Y., and Bouchon, M. (1980a), The seismic response of sediment-filled valleys. Part 1. The case of incident SH waves, Bull. Seism. Soc. Am., 70, 1263–1286.Google Scholar
  2. Bard, P.-Y., and Bouchon, M. (1980b), The seismic response of sediment filled valleys. Part-2. The case of incident P and SV waves, Bull. Seism. Soc. Am., 70, 1921–1941.Google Scholar
  3. Clayton, R.W., and Engquist, B. (1977), Absorbing boundary conditions for acoustic and elastic wave equations, Bull. Seism. Soc. Am., 67, 1529–1540.Google Scholar
  4. Graves, R.W. (1996), Simulating seismic wave propagation in 3-D elastic media using staggered grid finite difference, Bull. Seism. Soc. Am., 86, 1091–1107.Google Scholar
  5. Graves, R.W., Pitarka, A., Somerville, P.G. (1998), Ground motion amplification in the Santa Monica area: effects of shallow basin edge structure, Bull. Seism. Soc. Am., 88, 1224–1242.Google Scholar
  6. Hallier, S., Chaljub, E., Bouchon, M., and Sekiguchi, H. (2008), Revisiting the basin-edge effect at Kobe during the 1995 Hyogo-Ken Nanbu earthquake, Pure and Applied Geophys., 165, 1751–1760.Google Scholar
  7. Hanks, T.C. (1975), Strong ground motion of the San Fernando, California earthquake: ground displacements, Bull. Seism. Soc. Am., 65, 193–225.Google Scholar
  8. IS—456 (2000), Plain and reinforced concrete—code of practice, Bureau of Indian Standards.Google Scholar
  9. IS—800 (1984), Code of practice for general construction in steel, Bureau of Indian Standards.Google Scholar
  10. Israeli, M., and Orszag, S.A. (1981), Approximation of radiation boundary conditions, J. Comp. Phys., 41, 115–135.Google Scholar
  11. Kawase, H. (1993), Effects of surface and subsurface irregularities in ‘Earthquake and ground motions’, part 1, chapter 3, 118–155, Architectural Institute of Japan.Google Scholar
  12. Kawase, H. (2002), Site Effects on Strong Ground Motions in ‘International Handbook of Earthquake and Engineering Seismology, part B, chapter 61, 1013–1030 (ed. Lee et al.).Google Scholar
  13. Kristek, J., Moczo, P., and Archuleta, R.J. (2002), Efficient methods to simulate planar free surface in the 3D 4th order staggered grid finite difference scheme, Stud. Geophys. Geod., 46, 355–381.Google Scholar
  14. Kumar, S., and Narayan, J.P. (2008), Implementation of absorbing boundary conditions in a 4th order accurate SH-wave staggered grid finite difference algorithm with variable grid size, Acta Geophysica, 56, 1090–1108.Google Scholar
  15. Kumar, S. (2008), Finite difference simulation of basin-edge induced and transduced surface waves (unpublished Ph.D. thesis).Google Scholar
  16. Levander, A.R. (1988), Fourth-order finite difference P-SV seismograms, Geophysics, 53, 1425–1436.Google Scholar
  17. Luo, Y., and Schuster, G. (1990) Parsimonious staggered grid finite differencing of the wave equation, Geophy. Res. Lett., 17, 155–158.Google Scholar
  18. Madariaga, R. (1976), Dynamics of an expanding circular fault, Bull. Seism. Soc. Am., 66, 163–182.Google Scholar
  19. Moczo, P., and Bard, P.Y. (1993), Wave-diffraction, amplification and differential motion near strong lateral discontinuities, Bull. Seism. Soc. Am., 83, 85–106.Google Scholar
  20. Moczo, P., Kristek, J., Vavrycuk, V.,Archuleta, R.J., and Halada,L. (2002), 3D heterogeneous staggered-grid finite-difference modelling of seismic motion with volume harmonic and arithmetic averaging of elastic moduli and densities, Bull. Seism. Soc. Am., 92, 3042–3066.Google Scholar
  21. Narayan, J.P. (2001a), Site specific strong ground motion prediction using 2.5-D modelling, Geophysical J. International, 146, 269–281.Google Scholar
  22. Narayan, J.P. (2001b), Site specific ground motion prediction using 3-D modelling, ISET J. Earthquake Technology, 38, 17–29.Google Scholar
  23. Narayan, J.P. (2003), 2.5-D simulation of basin edge effects on the ground motion characteristics, Proceedings of Indian Academy of Sciences (Earth and Planetary Sciences), 112, 463–469.Google Scholar
  24. Narayan, J.P. (2005), Study of basin-edge effects on the ground motion characteristics using 2.5-D modeling, Pure and Applied Geophys, 162, 273–289.Google Scholar
  25. Narayan, J.P., and Ram, A. (2006), Study of effects of underground ridge on the ground motion characteristics, Geophysical Journal International, 165, 180–196.Google Scholar
  26. Narayan, J.P., and Singh, S.P. (2006), Effects of soil layering on the characteristics of basin-edge induced surface waves and differential ground motion, Jr. of Earthquake Engineering 10, 595–616.Google Scholar
  27. Narayan, J.P., and Kumar, S. (2008), A 4th order accurate SH-wave staggered grid finite difference algorithm with variable grid size and VGR-stress imaging technique, Pure and Appl. Geophys., 165, 271–294.Google Scholar
  28. Ohminato, T., and Chouet, B.A. (1997), A free surface boundary condition for including 3-D topography in the finite difference method, Bull. Seism. Soc. Am., 87, 494–515.Google Scholar
  29. Olsen, K.B. (2000), Site amplification in the Los Angeles basin from 3D modelling of ground motion, Bull. seism. Soc. Am., 90, S77–S94.Google Scholar
  30. Oprsal, I., Donat, F., Martin, P. (2005), Deterministic earthquake scenario for the Basel area: simulation strong motions and site effect for Basel, Switzerland, Jr. Geophys. Res., 110, B04305.Google Scholar
  31. Oprsal, I., and Fah, D. (2007) 1D vs 3D strong ground motion hybrid modeling of site, and pronounced topography effects at Augusta Raurica, Switzerland—earthquakes or battles?, Proceedings of 4th International Conference on Earthquake Geotechnical Engineering, June 25–28, Greece, Paper No. 1416, 12 pp. 020-5892-9.Google Scholar
  32. Ozel, O., and Tsutomu, S. (2004), A site effects study of the Adapazari basin, turkey, from strong and weak motion data, Jr. Seismology, 8, 559–572.Google Scholar
  33. Panza, G.F., Schwab, F.A., and Knopoff, L. (1973), Multimode surface waves for selected focal mechanisms I. Dip-slip sources on a vertical fault plane, Geophys. J. R. Astr. Soc., 34, 265–278.Google Scholar
  34. Panza, G.F., Schwab, F.A., and Knopoff, L. (1975), Multimode surface waves for selected focal mechanisms—III. Strike-slip sources, Geophys. J. R. Astr. Soc., 42, 945–955.Google Scholar
  35. Pitarka, A., Irikura, K., Iwata, T., and Sekiguchi, H. (1998), Three-dimensional simulation of the near fault motion for the 1995 Hyogoken Nanbu (Kobe), Japan, earthquake, Bull. Seism. Soc. Am., 88, 428–440.Google Scholar
  36. Pitarka, A. (1999), 3-D elastic finite difference modelling of seismic motion using staggered grids with variable spacing, Bull. Seism. Soc. Am., 89, 54–68.Google Scholar
  37. Romanelli, F., Panza, G.F., and Vaccari F. (2004), Realistic modelling of the effects of asynchronous motion at the base of bridge piers, JSEE, 6, 19–28.Google Scholar
  38. Sato, T., Graves, R.W., and Somerville, P.G. (1999), 3-D finite difference simulation of long-period strong motions in the Tokyo Metropolitan Area during the 1990 Odawa earthquake (MS5.1) and the great 1923 Kanto earthquake (Ms8.2) in Japan, Bull. Seism. Soc. Am., 89, 579–607.Google Scholar
  39. Vidale, J.E., and Helmberger D.V. (1988), Elastic finite difference modelling of the 1971 San Fernando, California, earthquake, Bull. Seism. Soc. Am., 78, 122–141.Google Scholar
  40. Virieux, J. (1986), P-SV wave propagation in heterogeneous media, velocity stress finite-difference method, Geophysics, 51, 889–901.Google Scholar
  41. Zahradnik, J., and Priolo, E. (1995), Heterogeneous formulations of elastodynamic equations and finite-difference schemes, Geophys. Jr. Int., 120, 663–676.Google Scholar
  42. Zahradnik, J., Jech, J., and Moczo, P. (1990a), Approximate absorption correction for complete SH seismograms, Studia Geoph. Geod., 34, 185–196.Google Scholar
  43. Zahradnik, J., Jech, J., and Moczo, P. (1990b), Absorption correction for computation of a seismic ground response, Bull. Seism. Soc. Am., 80, 1382–1387.Google Scholar

Copyright information

© Birkhäuser / Springer Basel AG 2010

Authors and Affiliations

  1. 1.Department of Earthquake EngineeringIndian Institute of Technology RoorkeeRoorkeeIndia

Personalised recommendations