Investigation of factors influencing behavior of single geocell-reinforced bases under static loading
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.
Geosynthetics International 02/2012; 19(1):1-10. DOI:10.1680/gein.2012.19.1.1 · 1.17 Impact Factor
Geosynthetics International 04/2013; 20(2):47-61. DOI:10.1680/gein.13.00001 · 1.17 Impact Factor
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ABSTRACT: Footings are frequently subjected to combination of permanently downward loads (weight of the structures) and upward loads (e.g. earthquake, wind tension cables for suspension bridges, marine structures such as floating platforms and tension leg platforms) which may result in pullout forces much greater than the weight of the structure itself. Hence anchors of large uplift capacity are required that is capable of resisting tensile force with the support of surrounding soil in which anchor is embedded. The pullout force may be carried out by the deep footings such as the piles/belled piles. In this paper, a series of laboratory, pilot scale tests were performed to evaluate the uplift performance of belled piles embedded in Geocell-reinforced sand. The effect of Geocell thickness on the uplift resistance of pile is studied. The results show that, with increase in the thickness of Geocell reinforcement over the bell of pile, the pullout resistance of the belled pile significantly increases and its upward displacement decreases as compared with the unreinforced one while the efficiency of the reinforcement decreases by increasing the thickness of Geocell.3rd international conference on new development in soil mechanics and geotechnical engineering, Near East University, Nicosia, North Cyprus; 06/2012