Finite element modelling of rate-dependent ratcheting in granular materials

Abstract

International audienceThe present paper introduces a comprehensive model that is capable of describing the behaviour, under cyclic loading, of the granular materials used in railway tracks and road pavement. Its main thrust is the introduction of the ''Chicago'' law in a continuum approach to account for the ratcheting effects. It also emphasizes rate-dependency as a dissipative mechanism that acts independently or jointly with the ratcheting effect as well as the non-associated plasticity. The numerical procedure is based on the return mapping algorithm, where Newton's method is used to calculate the nonlinear consistency parameter of the flow rule and to obtain a consistent tangent modulus. The model was applied to specific numerical examples including multi-axial and cyclic loading conditions

Calculation of Pavement Permanent Deformation Using Perzyna’s Elasto-Viscoplastic Model

“…The numerical resolution of Eqs. [2][3][4][5][6][7][8][9] by means of return mapping algorithm is as follow.…”

“…In Ref. [9], the authors proposed that hardening modulus decreasing with number of load passes, whereas cumulative equivalent plastic strain is used in Refs. [8,10] as a quantity to characterize the deformation state of material instead of either number of load passes or total loading time.…”

The impact of uncertain parameters on ratchetting trends in hypoplasticity

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A General Solution for Implicit Time Stepping Scheme in Rate-dependant Plasticity

“…Numerical examples were analyzed using the traditional linear method and their suggested schemes using von Mises yield criterion and Prager's linear hardening rule. Karrech et al [13] introduced a comprehensive model that was capable to describe the behavior under cyclic loading. Voyiadjis et al [14] developed a thermodynamic consistent, small-strain, non-unified model to capture the irregular rate dependency including strain controlled inelastic responses of polymers at the glassy state.…”