Abstract
A stress-strain model called TESRA (Temporary Effects of Strain Rate and Acceleration), described in a non-linear three-component framework, has been developed to simulate the viscous effects on the stress-strain behaviour observed in an extensive series of drained plane strain compression (PSC) tests on clean sands. A similar model has been developed for the geosynthetic reinforcement also. The TESRA model was implemented into a generalized elasto-plastic isotropic strain-hardening nonlinear Finite Element code. The integration scheme to obtain the viscous and inviscid stress components according to the TESRA model in FEM analysis, which needs some specific considerations including the relevant choice of the suitable rate parameter, is described. The geosynthetic reinforcements were modelled by employing nonlinear elasto-plastic one-dimensional truss elements with three-component TESRA model. The axial force—axial strain—time relations of several types of geosynthetic reinforcements were successfully simulated by the present FE code called - “Geotechnical Nonlinear Analysis (GNA)”. The shear stress—shear (or axial) strain - time relations from two drained PSC tests on geosynthetic reinforced Toyoura sand were successfully simulated by the FE code embedded with the TESRA model. It is shown that the FE code can predict the time-dependent stress-strain behaviour of reinforced sand accurately without spending any significant extra computational time or storage.
