Bulletin of the Seismological Society of America; October 2000; v. 90; no. 5;
p. 1313-1317; DOI: 10.1785/0120000008
© 2000 Seismological Society of America
Effects of Pore-Water Saturation on Seismic Reflection and Transmission from a Boundary of Porous Soils
Jun Yang and
Tadanobu Sato
Disaster Prevention Research Institute
Kyoto
University
Gokasho, Uji, Kyoto 611-0011,
JAPAN
yang{at}catfish.dpri.kyoto-u.ac.jp
Recent analysis of array observations indicated that pore-water saturation
of soils may strongly affect vertical site amplification. A study is therefore
motivated to investigate the saturation effect on seismic reflection from a
boundary of porous soils. The problem described herein corresponds to a
P- or SV-wave incident at the interface between rock
formation and overlying sand. The sand is modeled as a partially
water-saturated porous material while the rock is approximately regarded as
ordinary one-phase solids. Preliminary results show that in either P-
or SV-wave incidence, even a slight decrease of the complete
saturation may lead to a substantial influence on both reflected and
transmitted waves as well as the amplitude ratios between horizontal and
vertical motion at the interface, and this influence is dependent on the angle
of incidence. The underlying suggestion is that we may need to carefully
consider the saturation effect in the interpretation of field observations,
especially in such situations that partial saturation may very probably take
place.
Copyright © 2009 by Seismological Society of America