A Numerical Study on Stress-Strain Responses of Biaxial Geogrids under Tension at Different Directions

Biaxial geogrids are manufactured with ribs oriented in two perpendicular directions to carry loads in these two directions. In real applications, applied loads may not necessarily follow the orientations of these ribs. How the geogrid responds if subjected to a tensile load at different directions is not well understood. In this study, the numerical software — FLAC was adopted to investigate the effect of the loading direction on the stress-strain response of a biaxial geogrid. The geogrid ribs were modeled using beam elements jointed at nodes and subjected to tension in one direction. The numerical results show that the stress-strain responses of the geogrids are different at different loading directions. The tensile strength of the geogrid, when subjected to a load in the direction different from the machine or cross-machine direction, is much lower than that loaded in the machine or cross-machine direction.