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The Influence Of Grain-Size Characteristics in Determining
the Liquefaction Potential of a Soil Deposit by the Energy Method
Primary Researchers:
J.
Ludwig Figueroa
Department
of Civil Engineering
Case
Western Reserve University, Cleveland,
OH 44106, USA
E-mail: jlf@po.cwru.edu,
Tel. (216) 368-6247
Adel
S. Saada
Department
of Civil Engineering
Case
Western Reserve University, Cleveland,
OH 44106, USA
E-mail: axs31@po.cwru.edu,Tel.
(216) 368-2427
Slides
from M. Rokoff Seminar November 1998
Abstract:
The significant influence of parameters such as relative
density and effective confining pressure in determining the amount of unit
energy required for liquefaction was previously demonstrated. Similarly,
it was found that the unit energy was nearly independent of the shear strain
amplitude and the loading rate. Grain-size distribution has been traditionally
identified as one of the most important factors affecting the liquefaction
characteristics of sands. Torsional shear liquefaction testing of several
soils with different grain-size characteristics made possible the development
of a simple statistical relationship including relative density, effective
confining pressure and well known grain-size distribution parameters such
as uniformity coefficient and coefficient of curvature, to determine the
amount of unit energy required for liquefaction. Inclusion of the latter
two parameters considers the influence of particle size range as well as
symmetry and shape of the gradation curve on the unit energy level required
for liquefaction. Such statistical regression equation provides a measure
of the resistance of a soil to liquefaction, in terms of energy per unit
volume. This value can then be compared with the unit energy induced by
a credible earthquake as determined by a suitable site response model to
vertically propagating shear waves, to determine the liquefaction potential
of a soil deposit.
CWRU Department of Civil Engineering
Communication
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