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Lateral spreading of liquefied saturated sandy deposits happens during and shortly afterearthquakes. This paper first reviews this phenomenon by means of reviewing and comparingobservations on case histories and experimental works. Based on the results from the review andcomparison, a mechanism for describing lateral spreading will be suggested. The Finn model,adopted in the Computer code FLAC is employed to carry out numerical analyses of lateralspreading of the Wildlife Site, happened during the 1987 Superstition Hills earthquake. First themodel is calibrated by means of numerical analysis of the first centrifuge model test of theVELACS Project. For the Wildlife site, three types of analysis are carried out: a) coupledliquefaction-consolidation analysis using the coefficient of permeability (K1) of the liquefiedlayers, as reported in the literature b) analysis type (a), but with K equal to 0.1K1, and c) a fullyundrained liquefaction analysis. The analyses results, in forms of excess pore water pressures andsurface displacements, indicated that the fully undrained behavior of the liquefied layers betterrepresents the behavior and response of the site during the earthquake.

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This paper presents the results of a series of monotonic and post-cyclic triaxial tests carried out on a clay specimen and three types of clay-sand mixed specimens. The focus of the paper is on the post-cyclic mechanical behavior of the mixed specimens, as compared to their monotonic behavior. Analyses of the tests results show that cyclic loading degrade undrained shear strength and deformation modulus of the specimens during the post-cyclic monotonic loading. The degradation depends on the sand content, the cyclic strain level and to some degrees to the consolidation pressure.

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Mixed clayey soils occur as mixtures of sand (or gravel) and clay in widely varying proportions. Their

engineering behavior has not been comprehensively studied yet. An experimental program, comprising monotonic,

cyclic, and post-cyclic triaxial tests was undertaken on compacted clay-granular material mixtures, having different

proportions of clay and sand or gravel. This paper presents the results of cyclic triaxial tests and explains the behavior

of the mixtures based on number of loading cycles, cyclic strain amplitude, granular material content, grain size, and

effective confining pressure. The results indicate an increase in degree of degradation and cyclic loading-induced pore

water pressure as the number of loading cycles, cyclic strain and granular material content increase. Also the results

show that the grain size has no significant effect on the degree of degradation and cyclic loading-induced pore water

pressure in the specimens. The effect of granular material content on pore water pressure during cyclic loading in

equal-stress-level was also examined. The pore water pressure increases with the increase of granular material

content.

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Evaluating the rate and maximum height of capillary rise is of prime interest in unsaturated soil mechanics. Antecedent solutions

to this problem have dwelled mostly on determining the maximum capillary rise height, overlooking moisture and suction changes

in the capillary region. A comprehensive improved solution for the capillary rise of water in soils is presented. Salient features of

the formulation including consideration of initial soil suction (if any) prior to capillary rise, and determination of water content

variation in the capillary region are elaborately discussed. Results reveal that suction head variation within the capillary region

is non-linear, where the curvature decreases as water rises to higher elevations. The solution is verified and compared with

existing solutions, by means of two sets of experimental data available in the literature. The comparison suggests that the

improved formulation is more accurate and versatile than previous solutions for capillary rise.

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This paper studies thoroughly and deeply the results of about one hundred triaxial compression tests on thirty types of rockfill
materials. The materials are categorized in accordance with their particles shape (angular / rounded) and gradation
characteristics. The main tool of the study is the Hyperbolic Model developed by Duncan and Chang. The focus of the study is
on the variations of deformation modulus of the materials (Ei and Et) with confining stress (&sigma3). Features of the mechanical
behavior of the rockfill materials, as compared with the general behavior of soils, are highlighted through the exponent
parameter (n) of the Hyperbolic Model. It is shown that high confining stresses may have adverse effects on the deformation
modulus of the rockfill materials and make them softer. The particle breakage phenomenon which happens during compression
and shearing is found as the main factor responsible for the above effects and, in general, responsible for controlling the
behavior of the materials. For the rockfill materials of this study, two correlations for estimating the initial elasticity modulus (Ei)
and the internal friction angle (&phi) in terms of particles shape, confining pressure (&sigma3), and coefficient of uniformity (Cu) are
suggested.

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This paper presents results of a thorough study on the phenomenon of rupture propagation of reverse faults from the bedrock

foundation through homogeneous clayey embankments, mainly at the end of construction, with complementary analyses for the

steady state seepage through the embankment. The study is performed by means of numerical analyses with a nonlinear Finite

Element Method, verified beforehand through simulating fault propagations in an existing horizontal soil layer experiment.

Multiple cases considering three slopes & three clayey soils for the embankment and five fault dip angles, activated in several

locations of base of the embankment, are analyzed. The results show that ruptures in the embankment follow optimal paths to

reach the surface and their near-surface directions are predictable with respect to corresponding theories of classical soil

mechanics. Various types of rupture in the embankment are produced on the basis of the rupture types, the embankment base is

divided into three distinguishable zones, which can be used for interpretation of fault ruptures behavior. The effects of materials

and slope of the embankment, fault dip angle, and fault’s point of application in the bedrock-soil interface on the rupture paths

are studied in depth.