Experimental Study on the Effect of Geocell on the Behavior of the Strip Footing Resting on the Soil Slope

Document Type : Research Paper

Authors

1 MSc student, Faculty of Civil Engineering, Babol Noshirvani University of Technology, Babol, Iran

2 Civil Engineering Faculty, Babol Noshirvani University of Technology

Abstract

Soil slopes may need to be stabilized due to geometrical conditions, material parameters, and applied loads. Geosynthetics-reinforcement is one of the solutions to stabilize soil slopes, especially under surcharge. The use of geocells as a 3D geosynthetics reinforcement has become very widespread. In this study, using small-scale physical model tests, the role of geocells in evaluating the behavior of strip foundations resting on soil slope with an angle 70° has been investigated. The results showed that in order to increase the bearing capacity of the foundation resting on a steep soil slope, a certain number of geocells are needed and if more than three layers are used, the bearing capacity of the foundation increases. The bearing capacity of soil slope reinforced by three and four geocell layers is 3.6 and 4.9 times that of unreinforced ones, respectively. Due to the membrane behavior of geocells, it causes that the load transfers to the subsoil layers, and if number of reinforcing layers is low, the slope will be failed under relatively low-intensity surcharge. The use of geocells increases the stiffness of the soil slope and reduces the rotation of the foundation and the horizontal displacement of the slope crest compared to the unreinforced case. Also, the use of a sufficient number of geocell layers makes the slope able to absorb more energy and withstand more displacements before failure. Increasing the geocell spacing from 75 to 100 mm has reduced the efficiency of the reinforced slope so that the bearing capacity has decreased by about 35% compared to the geocell with smaller spacing. Also, the stiffness of the reinforced slope decreased by increasing the reinforcement spacing. The bearing capacity of a foundation with an embedment depth of 100 mm is 1.3 times the bearing capacity of a foundation located on a reinforced slope.

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Alamshahi, S. and Hataf, N. 2009. “Bearing capacity of strip footings on sand slopes reinforced with geogrid and grid-anchor”. Geotext. Geomembranes, 27(3): 217-226.
ASTM. 2011. “Standard test method for tensile properties of geotextiles by the wide-width strip method”. ASTM International.
Berg, R. R., Christopher, B.R. and Samtani, N.C. 2009. “Design of mechanically stabilized earth walls and reinforced soil slopes”. Federal Highway Administration, Washington, DC, USA.
Borthakur, B., Nambiar, M., Biswas, A. and Kalitha, U. 1988. “Studies on the bearing capacity of strip footing on slopes”. Proceedings of the Indian Geotechnical Conference, Bombay.
Chen, R. and Chiu, Y. 2008. “Model tests of geocell retaining structures”. Geotext. Geomembranes, 26(1): 56-70.
Choudhary, A., Jha, J. and Gill, K. 2010. “Laboratory investigation of bearing capacity behaviour of strip footing on reinforced flyash slope”. Geotext. Geomembranes, 28(4): 393-402.
Dash, S. K., Rajagopal, K. and Krishnaswamy, N. 2007. “Behaviour of geocell-reinforced sand beds under strip loading”. Can. Geotech. J., 44(7): 905-916.
El Sawwaf, M. A. 2007. “Behavior of strip footing on geogrid-reinforced sand over a soft clay slope”. Geotext. Geomembranes, 25(1): 50-60.
Fahliani, H. K., Arvin, M. R., Hataf, N. and Khademhosseini, A. 2021. “Experimental model studies on strip footings resting on geocell-reinforced sand slopes”. Int. J. Geosynth. Ground Eng., 7(2): 1-15.
Huang, C. C., Tatsuoka, F. and Sato, Y. 1994. “Failure mechanisms of reinforced sand slopes loaded with a footing”. Soils Found., 34(2): 27-40.
Javankhoshdel, S. and Bathurst, R. J. 2016. “Influence of cross correlation between soil parameters on probability of failure of simple cohesive and c-ϕ slopes”. Can. Geotech. J., 53(5): 839-853.
Kazemian, T. and Arvin, M. R. 2019. “Three-dimensional stability of locally loaded geocell-reinforced slopes by strength reduction method”. Geomech. Geoeng., 14(3): 185-201.
Mehdipour, I., Ghazavi, M. and Moayed, R. Z. 2013. “Numerical study on stability analysis of geocell reinforced slopes by considering the bending effect”. Geotext. Geomembranes, 37: 23-34.
Mehrjardi, G. T., Ghanbari, A. and Mehdizadeh, H. 2016. “Experimental study on the behaviour of geogrid-reinforced slopes with respect to aggregate size”. Geotext. Geomembranes, 44(6): 862-871.
Selvadurai, A. and Gnanendran, C. 1989. “An experimental study of a footing located on a sloped fill: influence of a soil reinforcement layer”. Can. Geotech. J., 26(3): 467-473.
Viswanadham, B. and König, D. 2004. “Studies on scaling and instrumentation of a geogrid”. Geotext. Geomembranes, 22(5): 307-328.
Yoo, C. 2001. “Laboratory investigation of bearing capacity behavior of strip footing on geogrid-reinforced sand slope”. Geotext. Geomembranes, 19(5): 279-298.