Centrifuge modelling of geogrid reinforced soil walls subjected to pseudo-static loading

A study on centrifuge modelling of geogrid reinforced soil walls was carried out through centrifuge tilting table tests. Special attention was focused on the effect of the properties of geogrid and backfill material, and the interaction between geogrid and backfill material on the seismic stability of geogrid reinforced soil walls using different types of model geogrids and backfill materials. As a result, it was found that the seismic stability of geogrid reinforced soil walls is highly influenced by the tensile stiffness of the geogrid and the deformation modulus of the backfill material. The geogrid reinforced soil walls collapsed after clear formation of slip lines in the reinforced area due to failure of the backfill material. The effects of disagreements about similitude in this test series on the behaviour of geogrid reinforced soil walls are discussed with results of centrifuge tilting table tests and stability analyses with the two-wedge method. It was found that the pullout resistance at the displacement corresponding to the failure of geogrid reinforced soil walls should be used in the seismic stability analysis rather than the peak pullout resistance.