### Abstract

A mathematical relation is presented for predicting the value of the contact normal plane distribution or the anisotropy parameter "α" (the ratio of the second invariant to the trace of fabric tensor) for granular materials under shearing loads. The changes of the contact normal planes are attributed to the mobilized stress ratio, internal friction angle, fabric principal direction and non-coaxiality between the major principal directions of stress and fabric. A new relationship between "α" and the main factors is derived by focusing on two particles across a potential sliding plane and the peanut-shaped function for the distribution of the contact normals. This formulation is obtained by combining the contact normal distribution function and mobilized stress ratio for sliding planes in a micro-level analysis. The dependence of "α" on the internal mobilized friction angle and the shear to normal stress ratio are the main characteristics of this relationship. The degree of anisotropy is easily obtained by applying this equation. The variation of the inter-particle mobilized friction angle in micro-level and double-shearing is briefly discussed. The variation of "α" with shear strain is similar to the variation of the shear to normal stress ratio with shear strain. The inter-particle mobilized friction angle with shearing approaches the mobilized stress ratio on the spatial mobilized plane. A comparison with experimental tests demonstrates the validity of this formula for the evolution of anisotropy.

Original language | English |
---|---|

Pages (from-to) | 173-184 |

Number of pages | 12 |

Journal | Mechanics of Materials |

Volume | 69 |

DOIs | |

Publication status | Published - 2014 |

### Fingerprint

### Keywords

- Anisotropy
- Fabric
- Granular materials
- Non-coaxiality
- Simple shear test

### ASJC Scopus subject areas

- Instrumentation
- Materials Science(all)
- Mechanics of Materials

### Cite this

**Evolution of fabric under the rotation of the principal stress axes in the simple shear test.** / Taha, Mohd. Raihan; Shaverdi, Homayoun.

Research output: Contribution to journal › Article

*Mechanics of Materials*, vol. 69, pp. 173-184. https://doi.org/10.1016/j.mechmat.2013.10.003

}

TY - JOUR

T1 - Evolution of fabric under the rotation of the principal stress axes in the simple shear test

AU - Taha, Mohd. Raihan

AU - Shaverdi, Homayoun

PY - 2014

Y1 - 2014

N2 - A mathematical relation is presented for predicting the value of the contact normal plane distribution or the anisotropy parameter "α" (the ratio of the second invariant to the trace of fabric tensor) for granular materials under shearing loads. The changes of the contact normal planes are attributed to the mobilized stress ratio, internal friction angle, fabric principal direction and non-coaxiality between the major principal directions of stress and fabric. A new relationship between "α" and the main factors is derived by focusing on two particles across a potential sliding plane and the peanut-shaped function for the distribution of the contact normals. This formulation is obtained by combining the contact normal distribution function and mobilized stress ratio for sliding planes in a micro-level analysis. The dependence of "α" on the internal mobilized friction angle and the shear to normal stress ratio are the main characteristics of this relationship. The degree of anisotropy is easily obtained by applying this equation. The variation of the inter-particle mobilized friction angle in micro-level and double-shearing is briefly discussed. The variation of "α" with shear strain is similar to the variation of the shear to normal stress ratio with shear strain. The inter-particle mobilized friction angle with shearing approaches the mobilized stress ratio on the spatial mobilized plane. A comparison with experimental tests demonstrates the validity of this formula for the evolution of anisotropy.

AB - A mathematical relation is presented for predicting the value of the contact normal plane distribution or the anisotropy parameter "α" (the ratio of the second invariant to the trace of fabric tensor) for granular materials under shearing loads. The changes of the contact normal planes are attributed to the mobilized stress ratio, internal friction angle, fabric principal direction and non-coaxiality between the major principal directions of stress and fabric. A new relationship between "α" and the main factors is derived by focusing on two particles across a potential sliding plane and the peanut-shaped function for the distribution of the contact normals. This formulation is obtained by combining the contact normal distribution function and mobilized stress ratio for sliding planes in a micro-level analysis. The dependence of "α" on the internal mobilized friction angle and the shear to normal stress ratio are the main characteristics of this relationship. The degree of anisotropy is easily obtained by applying this equation. The variation of the inter-particle mobilized friction angle in micro-level and double-shearing is briefly discussed. The variation of "α" with shear strain is similar to the variation of the shear to normal stress ratio with shear strain. The inter-particle mobilized friction angle with shearing approaches the mobilized stress ratio on the spatial mobilized plane. A comparison with experimental tests demonstrates the validity of this formula for the evolution of anisotropy.

KW - Anisotropy

KW - Fabric

KW - Granular materials

KW - Non-coaxiality

KW - Simple shear test

UR - http://www.scopus.com/inward/record.url?scp=84887853705&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84887853705&partnerID=8YFLogxK

U2 - 10.1016/j.mechmat.2013.10.003

DO - 10.1016/j.mechmat.2013.10.003

M3 - Article

VL - 69

SP - 173

EP - 184

JO - Mechanics of Materials

JF - Mechanics of Materials

SN - 0167-6636

ER -