Article

Investigation of factors influencing behavior of single geocell-reinforced bases under static loading

Geotextiles and Geomembranes - GEOTEXT GEOMEMBRANE 01/2010; 28(6):570-578. DOI: 10.1016/j.geotexmem.2010.06.002

ABSTRACT Geocell, one type of geosynthetics manufactured in the form of three-dimensional interconnected cells, can be used as a reinforcement to improve the behavior of base courses by providing lateral confinement to increase their stiffness and strength and reduce surface permanent-deformation. However, the use of geocells for base reinforcement is hindered by the existing gap between applications and theories. This study experimentally investigated the factors influencing the behavior (stiffness and bearing capacity) of single geocell-reinforced bases including shape, type, embedment, height of geocells, and quality of infill materials. Three of the four types of geocells investigated in this study were made of novel polymeric alloys using a new manufacturing technology. Repeatability and potential scale effects on test results were examined. The test results showed that the geocell placed in a circular shape had a higher stiffness and bearing capacity than that placed in an elliptical shape. The performance of the geocell-reinforced base depended on the elastic modulus of the geocell sheet. The unconfined geocell had a lower stiffness but a higher ultimate load capacity than the confined geocell. The benefit of the geocell was minimized when the infill material, quarry waste with apparent cohesion, was used as compared with the Kansas River sand without apparent cohesion. The single geocell-reinforced base had a lower stiffness and bearing capacity than the multiple geocell-reinforced base.

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