Shear strength of assemblies of ellipsoidal particles

Ng, T. T.

doi:10.1680/geot.2004.54.10.659

Cited by 54 publications

(14 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The pattern of variation in j9 peak with b is similar to those reported in experimental studies of Sutherland & Mesdary (1969) and Haruyama (1981) and also to the DEM simulations of Ng (2004b). Additionally, the DEM true triaxial studies of Thornton (2000), Ng (2004a) and Barreto & O'Sullivan (2012) have been compared against the Lade & Duncan (1973) failure criterion in terms of failure stress state and have demonstrated a reasonable agreement.…”

Section: Dem Simulationssupporting

confidence: 80%

“…Such a response is typical for this type of sample and is termed a type 1 response by Roux & Combe (2010). A similar initial stiff response was noted by Ng (2004a) in his true triaxial DEM simulations using ellipsoidal particles and by Thornton (2000) using spherical particles. The pattern of variation in j9 peak with b is similar to those reported in experimental studies of Sutherland & Mesdary (1969) and Haruyama (1981) and also to the DEM simulations of Ng (2004b).…”

Section: Dem Simulationssupporting

confidence: 61%

See 1 more Smart Citation

Quantifying stress-induced anisotropy using inter-void constrictions

Shire¹,

O’Sullivan²,

Barreto³

et al. 2013

Géotechnique

View full text Add to dashboard Cite

In particulate geomechanics it is common to quantify fabric anisotropy using contact and particle orientations. Measurement of void anisotropy is less common, most likely owing to the difficulties associated with defining individual voids. Here a Delaunay tessellation-based approach is applied to measure anisotropy of the inter-void constriction orientations. This new measure of fabric anisotropy was capable of identifying stress-induced anisotropy in discrete-element modelling true triaxial simulations with spherical particles. A relationship is established between the constriction orientations, the macro-scale principal stress directions and the micro-scale contact normal orientations.

show abstract

Section: Dem Simulationssupporting

confidence: 80%

Section: Dem Simulationssupporting

confidence: 61%

Quantifying stress-induced anisotropy using inter-void constrictions

Shire¹,

O’Sullivan²,

Barreto³

et al. 2013

Géotechnique

View full text Add to dashboard Cite

show abstract

“…These are in addition to the simulation results with spherical particles (AR=1.0) shown in Previous studies [10,30,33] show that the DEM results compare well with the Lade and Duncan [34] failure criterion defined by: , which, again, might be subjected to further verification by additional data.…”

supporting

confidence: 79%

The influence of particle geometry and the intermediate stress ratio on the shear behavior of granular materials

et al. 2017

View full text Add to dashboard Cite

The behavior of granular materials is very complex in nature and depends on particle shape, stress path, fabric, density, particle size distribution, amongst others. This paper presents a study of the effect of particle geometry (aspect ratio) on the mechanical behaviour of granular materials using the Discrete Element Method (DEM). This study discusses 3D DEM simulations of conventional triaxial and true triaxial tests. The numerical experiments employ samples with different particle aspect ratios and a unique particle size distribution (PSD). Test results show that both particle aspect ratio (AR) and intermediate stress ratio (b=(σ2'-σ3')/(σ1'-σ3')) affect the macroand micro-scale responses. At the macro-scale, the shear strength decreases with an increase in both aspect ratio and intermediate stress ratio b values. At the micro-scale level, the fabric evolution is also affected by both AR and b. The results from DEM analyses qualitatively agree with available experimental data. The critical state behaviour and failure states are also discussed. It is observed that the position of the critical state loci in the compression (e-p') space is only slightly affected by aspect ratio (AR) while the critical stress ratio is dependent on both AR and b. It is also demonstrated that the influence of the aspect ratio and the intermediate stress can be captured by micro-scale fabric evolutions that can be well understood within the framework of existing critical state theories. It is also found that for a given stress path, a unique critical state fabric norm is dependent on the particle shape but is independent of critical state void ratio.

show abstract

“…While a DEM model uses relatively simple particle geometries, it is a useful approach to understand better the micro-scale interactions in the triaxial tests. A number of DEM simulations of triaxial tests have been performed by earlier researchers, including Thornton (2000), O'Sullivan et al (2003), Ng (2004), and Tsunekawa & Iwashita (2001). The boundary conditions used in these earlier studies were periodic boundaries, rigid boundaries, hydrostatic boundaries and flexible membrane boundaries respectively.…”

Section: Introductionmentioning

confidence: 99%

An analysis of the triaxial apparatus using a mixed boundary three-dimensional discrete element model

2007

View full text Add to dashboard Cite

The triaxial test is probably the most important fundamental laboratory test for geotechnical engineers. The objective of the study presented here was to gain insight into the micro-scale interactions experienced by particles during a triaxial test using the distinct element method (DEM). To achieve this objective, a novel DEM modelling environment to simulate triaxial tests on ideal granular materials was implemented, as described here. In this test environment, both the stress conditions and boundary conditions in the physical tests can be accurately reproduced. This approach was quantitatively validated by simulating a number of physical triaxial tests on specimens of steel spheres. A comparison between the circumferential periodic boundaries used here and the circumferential rigid boundaries used by other researchers emphasises the significance of maintaining a continuous particle-particle contact network orthogonal to the major principal stress direction.Results of an analysis of the micro-scale response in a triaxial simulation are analysed in detail, including the stresses, the distribution of contact forces, the evolution of fabric, the distribution of local strains, and the particle rotations. Significant non-uniformities in the stresses, strains and contact fabric were observed.

show abstract

Shear strength of assemblies of ellipsoidal particles

Cited by 54 publications

References 12 publications

Quantifying stress-induced anisotropy using inter-void constrictions

Quantifying stress-induced anisotropy using inter-void constrictions

The influence of particle geometry and the intermediate stress ratio on the shear behavior of granular materials

An analysis of the triaxial apparatus using a mixed boundary three-dimensional discrete element model

Contact Info

Product

Resources

About