A Comprehensive constitutive equation for granular materials

• Autorzy: Gudehus G.
• Języki publikacji: EN

Abstrakty

EN

constitutive equation is proposed for describing changes of states of granular materials, which are sufficiently characterised by the void ratio and the stress tensor. It may be considered as an extension of the Critical State concept. It is based on recently published hypoplastic equations and covers a wide range of densities, pressures and deformations. A factorial decomposition allows a rather easy separation and determination of material parameters. Two factors depend on a relative void ratio so that it remains within lower and upper bounds. The bounding void ratios decrease monotonously from maximal values to zero with increasing pressure. The same reduction of the void ratio is proposed for an isotropic compression starting from a suspension. Thus a granulate hardness is defined, and a stiffness factor can be determined. Four material parameters can be estimated from classification tests and determined from the asymptotic behaviour in element tests. Four further parameters are determined by calibration; they are rather constant for wide groups of materials. Strength and stiffness values can be derived and used for the analysis of deformations, stability, and flow. The viscous behaviour is modelled by a rate dependent factor with one further parameter. Limitations and possible extensions of this comprehensive approach are also outlined.

Słowa kluczowe

EN

constitutive equation of soil; critical state; deformation; granular materials; stability analysis

• Wydawca: Politechnika Gdańska
• Czasopismo: TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
• Rocznik: 2000
• Tom: Vol. 4, No 3
• Strony: 319--342
• Opis fizyczny: Bibliogr. 21 poz., rys

Twórcy

autor

Gudehus G.

• Institute for Soil Mechanics and Rock Mechanics, University of Karlsruhe, Enger-Bunte-Ring, D-76128 Karlsruhe, Germany

Bibliografia

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