FINITE ELEMENT MODELLING OF SOIL-GEOGRID INTERACTION AND ITS APPLICATION IN THE STUDY OF THE PULLOUT BEHAVIOUR OF GEOGRIDS

A two dimensional finite element (FE) analysis is presented to predict the pullout bahaviour of geogrids embedded in fill materials. The interactions between fill material and geogrid are simulated by using nonlinear springs. The stiffness of the springs can be determined from simple tests in a specially designed shear box. The proposed FE analysis is applied to interpret test results from a large scale pullout test rig. The predicted behaviour of geogrid under pullout load agrees well with the observed data, including the load-displacement properties, the displacement distribution along the longitudinal direction and the mobilization of frictional and bearing resistances.