Non-Coaxial Theories of Plasticity for Granular Materials
نویسنده
چکیده
This Keynote Paper is concerned with the fundamental mechanics of granular materials with a particular reference to non-coaxial behaviour. The non-coaxial behaviour refers to the non-coincidence of principal stress directions and corresponding principal plastic strain rate directions during plastic deformation. At present, the majority of soil models used in geotechnical practice are those of a coaxial type and are not able to model the important non-coaxial behaviour. Failure to account for non-coaxial soil behaviour would lead to an unsafe design in geotechnical practice. This paper presents experimental and micromechanical evidence of the non-coaxial behaviour and its constitutive modelling using plasticity theory. In particular the paper proposes a new micromechanical fabric-based plasticity theory for modelling the non-coaxial behaviour of granular materials.
منابع مشابه
Constitutive Model for Multi-laminate Induced Anisotropic Double Hardening Elastic-plasticity of Sand
A constitutive multi-laminate based elastic-plastic model developed to be capable of accounting induced anisotropic behavior of granular material such as sand. The fabric feature or grain orientation characteristic effects through medium are considered in a rational way under any complex stress path, including cyclic loading. The salient feature of the developed model is a non-associative on pl...
متن کاملComparison of two integration schemes for a micropolar plasticity model
Micropolar plasticity provides the capability to carry out post-failure simulations of geo-structures due to microstructural considerations and embedded length scale in its formulation. An essential part of the numerical implementation of a micropolar plasticity model is the integration of the rate constitutive equations. Efficiency and robustness of the implementation hinge on the type of int...
متن کاملElastic/plastic Buckling Analysis of Skew Thin Plates based on Incremental and Deformation Theories of Plasticity using Generalized Differential Quadrature Method
Abstract In this study, generalized differential quadrature analysis of elastic/plastic buckling of skew thin plates is presented. The governing equations are derived for the first time based on the incremental and deformation theories of plasticity and classical plate theory (CPT). The elastic/plastic behavior of plates is described by the Ramberg-Osgood model. The ranges of plate geometries...
متن کاملDetermination of Thermo-physical Properties of Non-Newtonian Fluids Using a Coaxial Cylindrical Cell
In this study the thermal conductivity and the volumetric heat capacity of non-Newtonian fluids are investigated. These fluids find many applications in chemical, medical and food industries. They mostly have viscoelastic behavior and generally differ from Newtonian fluids. Two non-Newtonian fluids, solutions of xanthan and carboxy methyl cellulose in water with various concentrations have bee...
متن کاملA 2D constitutive non-linear model with anisotropy for granular materials
Dense granular materials behave differently from classical fluids or solids and can not be described through the continuum theories developed for those. In fact behavior at macro-scale is strongly related to smaller-scale field variables and kinetic processes. The influence of the micromechanics on the non-coaxiality of stress, strain and anisotropy of soils, is an essential part of a constitut...
متن کامل