ABSTRACT: The aim of this paper is to model the rate-dependent behavior of soft soil by means of a microstructural approach. A new microstructural elasto-viscoplastic model was developed, based on the granular mechanics approach and the overstress theory of Perzyna. The deformation of a representative volume of the material is generated by mobilizing particle contacts. Thus, the stress-strain r...

Most of the field problems in geotechnical engineering are in three dimensional state or close to a plane strain condition. Strength and deformation properties of soils in plane strain condition are considerably different from those in an axisymmetric condition. Many researchers have investigated the behaviour of soils under a plane strain condition. However, most of the previous studies have c...

this paper presents a model for prediction of the mechanical behavior of sand-gravel mixtures using generalized plasticity and critical state concepts. proposed model is based on the difference between critical state lines of sand and sand-gravel mixture in e-lnp' plane. a generalized plasticity model is considered as the base model for sandy soil. its state parameter, dilation rate and ha...

Liquefaction phenomenon in saturated loose sandy layers occurs as an undrained response of soil when it is subjected to static or dynamic loads. A fully coupled dynamic numerical program is developed to predict the liquefaction potential of saturated sandy layers. Coupled dynamic field equations of extended Biot’s theory with u-p formulation are used to determine pore fluid and soil skeleton re...

In this paper, application of energy-based excess pore pressure generation model proposed by Park et al. (2008) to develop an improved model for the analysis of liquefaction potential and to predict excess pore pressure (EPP) is examined through experimental and analytical investigations. For more realistic description of the dynamic responses of saturated sand undrained dynamic triaxial tests ...

SYNOPSIS Results of unconsolidated-undrained triaxial tests, field vane shear tests and cone penetration tests have been used to develop correlations between undrained shear strength and cone resistance for a soft to medium alluvial clay in the Lopez Canyon area of San Diego. When comparing uu triaxial results with cone resistance, the average cone factor was 11 with a standard deviation of 1.5...

Cone penetration resistance in sands with fines contents up to 35% is explored through drained cylindrical cavity expansion simulations with a modified MIT-S1 constitutive model. The constitutive model is calibrated to sands with 0%, 10%, 20%, and 35% low-plasticity fines with data from constant volume direct simple shear, drained and undrained triaxial compression, shear wave velocity, and 1D-...

To investigate the strength and deformation characteristics of gravelly sand on Qinghai-Tibet Plateau under different stress paths, a series triaxial shear tests was conducted confining pressures 50–400 kPa in four types path conditions conventional compression (CTC) (drained undrained), (TC), reduced (RTC). We can see from test results that samples show strain hardening contraction CTC (draine...

the present paper is devoted to a new critical state based plasticity model able to predict drained and undrained behaviour of granular material. it incorporates a bounding surface plasticity model describing in multilaminate framework to capitalize on advantages of this mathematical framework. most of the models developed using stress/strain invariants are not capable of identifying the parame...

[1] Pore fluid pressure plays an important role in the frictional strength and stability of tectonic faults. We report on laboratory measurements of porosity changes associated with transient increases in shear velocity during frictional sliding within simulated finegrained quartz fault gouge (d50 = 127 mm). Experiments were conducted in a novel true triaxial pressure vessel using the double-di...