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Title: Centrifuge tests to assess seismic site response of partially saturated sand layers
Seismic response of unsaturated soil layers may differ from that of saturated or dry soil deposits. A set of centrifuge experiments was conducted to study the influence of partial saturation on seismic response of sand layers under scaled Northridge earthquake motion. Steady state infiltration was implemented to control and provide uniform degrees of saturation profiles in depth. The amplification of peak ground acceleration at the soil surface was inversely proportional to the degree of saturation, especially in low period range. The cumulative intensity amplification of the motion was also higher in unsaturated soils with higher suctions. The lateral deformation and surface settlement of partially saturated sand with higher stiffness were generally lower than that in dry soil. Although neglecting the effect of partial saturation in sand layers might be conservative with respect to seismic deformations, it may result in underestimating the surface design spectra.  more » « less
Award ID(s):
1333810
PAR ID:
10478064
Author(s) / Creator(s):
;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Soil Dynamics and Earthquake Engineering
Volume:
94
Issue:
C
ISSN:
0267-7261
Page Range / eLocation ID:
254 to 265
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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