Showing papers in "Soils and Foundations in 2007"

TL;DR: In this paper, the behavior of the encased stone column stabilized bed is experimentally investigated and analyzed numerically, and material behaviour is simulated using Soft Soil, Mohr Coulomb and Geogrid models for clay, stone material and encasement respectively and validated with experimental results.

TL;DR: In this paper, a new constitutive model is proposed to describe the mechanical behaviors of soils under different loading conditions, which is able to describe not only the mechanical behavior of soil under monotonic loading, but also the behavior of the soils under cyclic loading with different drained condition.

TL;DR: In this article, a finite element-finite difference method (FE-FD) based on the constitutive model and two-phase field theory is used to simulate the repeated liquefaction-consolidation of sandy ground with different densities, such as the mechanical behavior pre-and during liquefactions, the settlement in post-liquefaction consolidation and the influence of density on the accumulation of excessive pore water pressure (EPWP) in repeated strong motions.

TL;DR: In this article, the authors show that the hypothetical conditions of the Mononobe-Okabe formula do not appropriately express the real behavior of backfill and gravity retaining walls during earthquakes.

TL;DR: In this paper, a reduction coefficient r (P-multiplier) is introduced to quantify the effects of cyclic loads on P-y reaction curves and an empirical law to evaluate pile head displacements at application point is proposed.

TL;DR: In this paper, the vertical bearing capacity of skirted foundations on normally consolidated undrained soil was investigated using numerical and physical modelling, and a design method was proposed to calculate vertical bearing capacities.

TL;DR: In this article, the Atterberg limits of six inorganic soils and their respective mixtures with fine silica sand were investigated and it was observed that the liquid limit and plastic limit values of the mixtures tested, except those with a low clay percentage, are linked to the respective clay size contents by a linear relationship.

TL;DR: In this article, an intensive laboratory study carried out on undisturbed soft Bangkok clay specimens to investigate the effect of temperature on shear strength and yielding behavior especially in states wetter than critical condition is presented.

TL;DR: In this article, a long-term hydraulic conductivity test for 3 years at longest was conducted on a non-prehydrated geosynthetic clay liners (GCLs) permeated with inorganic chemical solutions.

TL;DR: In this paper, a series of centrifuge and 1g model tests were conducted to study active arching in dry granular soil on circular trapdoors and the results showed that the minimum load on the trapdoor became constant at H/D equal to 5 regardless of the initial overburden pressure or height of the soil model.

TL;DR: In this article, a three-dimensional elastoplastic model for predicting the hydraulic and stress-strain-strength behavior of unsaturated soils is presented, where the shape of the failure surface and yield surface in the deviatoric plane of the average skeleton stress space are given by the SMP criterion.

TL;DR: In this article, a theoretical analysis was carried out to predict the loads transferred on the piles according to mobilizing soil arching in pile-supported embankments and the results showed good agreement with those measured in not only the presented test but also the previous test.

TL;DR: In this paper, a lattice-shaped ground improvement by mixing with cement was investigated using numerical analysis, where both elastic and elasto-plastic models were used for expressing the behavior of the improved ground.

TL;DR: In this paper, the K-stiffness method was re-examined using a total of six new case studies-five from Japan and one from the USA-to estimate the magnitude and distribution of reinforcement loads for internal stability design of vertical-faced geosynthetic reinforced soils walls with granular backfills.

TL;DR: In this article, a technique called the cement-mixing and mechanical dehydration method (CMD) was developed to increase the strength of soft clay slurry by using a series of unconfined compression tests and several durability tests.

TL;DR: In this article, a simple elasto-plastic model that simulates the behavior of cement-treated sands under a general three-dimensional stress state was used for these analyses and the analytical results showed that the direct tension tests yield reliable values of the actual tensile strength that will be mobilized under an ideal condition of uniaxial tension.

TL;DR: In this paper, the problem of determining the best profile for a c, φ soil slope with reference to rigid rotational failure mechanisms is tackled, and the upper bound values of collapse load are determined.

TL;DR: The potential for creep deformations is exaggerated and design modulus values are underestimated when based on small sample laboratory tests as discussed by the authors, which can lead to a misleading interpretation of field results.

TL;DR: In this paper, a series of CW and CD triaxial tests were carried out on a statically compacted silt and the results showed that the critical state lines at different matric suctions on the (q-p) plane were parallel with a slope of 1.28 for both the constant water content (CW) and consolidated drained (CD) tests, indicating the unique relationship between deviator stress and mean net stress.

TL;DR: In this article, the effects of soil nonlinearity arising from the increased intensity of base excitation and/or decreased "plasticity" index* of the clayey soil material were analyzed.

TL;DR: In this paper, a well-instrumented field study was carried out on an unsaturated expansive soil slope in China, where two neighboring monitoring areas (both 16 m wide by about 30 m long) were compared and discussed.

TL;DR: In this paper, three series of unsaturated triaxial shear tests were conducted on a compacted expansive clay with an initial degree of saturation of 82%. Two of these series were performed using the axis-translation and osmotic techniques at HKUST.

TL;DR: In this paper, a comprehensive series of triaxial compression tests have been performed on two air-dried poorly graded fine sands (Hostun and Toyoura sands) and on a moist mixture of sand and clay (hostun sand-Kaolin clay).

TL;DR: In this paper, the effects of long-term curing on the strength and deformation characteristics of compacted cement-mixed soil were evaluated and the ageing effects on the compressive strength, qmax, from the present study were compared to those with various types of cementmixed soils and concretes from the literature.

TL;DR: In this article, a chronology of events of the collapse of the Showa Bridge was established based on the testimony from eyewitnesses of the bridge collapse with the objective of pinning down the cause of the collapsed bridge.

TL;DR: In this article, the viscous properties of three types of geogrid polymer were evaluated by sustained loading tests lasting for 30 days at a load level about a half of its nominal rupture strength.

TL;DR: In this paper, the behavior of coal bottom ash sampled in southern Brazil, ranging from very small to very large shear strains, as well as to high isotropic pressures, to determine its complete behavior.

TL;DR: A comparative study of the NGI Direct Simple Shear Test (DSST) and the Mikasa Direct Shear test (DST) is reported in this paper, where samples from Norwegian Drammen clay and Japanese Ariake clay were subjected to both types of test.

TL;DR: In this article, the authors present a comparative study based on the observed orientation of shear band formation, and the intensity of strain localization (by estimating the maximum local strain) within the specimen during its shear deformation process.

TL;DR: In this article, a series of model clay liners subjected to non-uniform settlements with and without a geogrid layer embedded within the top one-third portion of the clay liner was examined.