Model Tests on Performance of Embankment Reinforced with Geocell Under Static and Cyclic Loading

Abstract

Geocell, a honeycomb geosynthetics, has been widely used in geotechnical engineering to improve the performances of embankments. A useful method, particle image velocimetry (PIV) technique which could track motion of soil grains, was used to determine the displacement field and the slip surface progressively. A series of experimental and analytical investigations on geocell-reinforced embankments were presented. This study focused on revealing the mechanics response and failure process of embankment under static and cyclic loading. The embankments were reinforced with geocells. And the experiments were scheduled to demonstrate the effect of the burial depth of the geocell layer, such as 0.83B, 1.67B and 2.50B (B, width of loading plate). Based on the sand displacement field, the deformation mechanisms of embankments were analyzed. Under the static loading, the steel plate would be forced down into the embankment, which made the large lateral deformation develop and progressively caused the collapse of embankments. Comparing the failure modes of different embankments, it could be found that the slip region area of reinforced embankments was wider than unreinforced embankments. Moreover, the similar phenomenon occurred in stress distribution. Under the cyclic loading condition, the results suggested that geocell-reinforcements provided more lateral confinement and reduced the cumulative plastic settlement. Analyzing the influence of burial depths, it could be concluded that shallower the geocell was embedded, the better stability of the embankment was.