Scale Effects of Footings on Geocell Reinforced Sand Using Large-Scale Tests

A. Shadmand, Mahmoud Ghazavi, Navid Ganjian

Abstract


The scale effect on bearing capacity of shallow footings supported by unreinforced granular soils has been evaluated extensively. However, the subject has not been addressed for shallow footings on geocell-reinforced granular soils. In this study, load-settlement characteristic of large square footings is investigated by performing large-scale loading tests on unreinforced and geocell-reinforced granular soils. The effects of footing width (B), soil relative density of soil (Dr), and reinforcement depth (u) have been investigated. The test results show that the scale effects exist in geocell-reinforced soils, like unreinforced soils, and the behavior of small-scale models of footings cannot be directly related to the behavior of full-scale footings due to the difference between initial conditions of tests and the initial state of mean stresses in the soil beneath the footings having different dimensions. Large footings create higher mean stresses in the soil, resulting in low soil friction angle and initial conditions of the test approach to the critical state lines. The results of tests indicate that model experiments should be conducted on low-density soil for better prediction of the behavior of full-scale footings, otherwise, the predicted behavior of full-scale footings does not seem conservative.


Keywords


Scale Effect; Geocell; Shallow Footing; Large-Scale; Sand.

References


Adams, Michael T., and James G. Collin. “Large Model Spread Footing Load Tests on Geosynthetic Reinforced Soil Foundations.” Journal of Geotechnical and Geoenvironmental Engineering 123, no. 1 (January 1997): 66–72. doi:10.1061/(asce)1090-0241(1997)123:1(66).

Al Khuzaie, H.M. “Verification of Scale Effect of Shallow Foundation in Determination of Bearing Capacity of Sandy Soil.” Al-Rafadain Engineering Journal 19, no. 2 (2011).

ASTM D1196M, (2012). “Test Method for Nonrepetitive Static Plate Load Tests of Soils and Flexible Pavement Components, for Use in Evaluation and Design of Airport and Highway Pavements” (n.d.). doi:10.1520/d1196-93r04.

Briaud, Jean-Louis, and Robert Gibbens. “Behavior of Five Large Spread Footings in Sand.” Journal of Geotechnical and Geoenvironmental Engineering 125, no. 9 (September 1999): 787–796. doi:10.1061/(asce)1090-0241(1999)125:9(787).

Cerato, Amy B., and Alan J. Lutenegger. “Scale Effects of Shallow Foundation Bearing Capacity on Granular Material.” Journal of Geotechnical and Geoenvironmental Engineering 133, no. 10 (October 2007): 1192–1202. doi:10.1061/(asce)1090-0241(2007)133:10(1192).

Dash, S. “Bearing Capacity of Strip Footings Supported on Geocell-Reinforced Sand.” Geotextiles and Geomembranes 19, no. 4 (May 2001): 235–256. doi:10.1016/s0266-1144(01)00006-1.

Dash, Sujit Kumar, K Rajagopal, and N.R Krishnaswamy. “Strip Footing on Geocell Reinforced Sand Beds with Additional Planar Reinforcement.” Geotextiles and Geomembranes 19, no. 8 (December 2001): 529–538. doi:10.1016/s0266-1144(01)00022-x.

Dash, S. “Model Studies on Circular Footing Supported on Geocell Reinforced Sand Underlain by Soft Clay.” Geotextiles and Geomembranes 21, no. 4 (August 2003): 197–219. doi:10.1016/s0266-1144(03)00017-7.

Dash, S. K., K. Rajagopal, and N. R. Krishnaswamy. “Performance of Different Geosynthetic Reinforcement Materials in Sand Foundations.” Geosynthetics International 11, no. 1 (January 2004): 35–42. doi:10.1680/gein.11.1.35.36317.

Dash, Sujit Kumar. “Effect of Geocell Type on Load-Carrying Mechanisms of Geocell-Reinforced Sand Foundations.” International Journal of Geomechanics 12, no. 5 (October 2012): 537–548. doi:10.1061/(asce)gm.1943-5622.0000162.

De Beer, E. E. “The Scale Effect in the Transposition of the Results of Deep-Sounding Tests on the Ultimate Bearing Capacity of Piles and Caisson Foundations.” Géotechnique 13, no. 1 (March 1963): 39–75. doi:10.1680/geot.1963.13.1.39.

DeMerchant, M.R, A.J Valsangkar, and A.B Schriver. “Plate Load Tests on Geogrid-Reinforced Expanded Shale Lightweight Aggregate.” Geotextiles and Geomembranes 20, no. 3 (June 2002): 173–190. doi:10.1016/s0266-1144(02)00006-7.

Fakher, Ali, and Colin J. F. P. Jones. “Discussion: Bearing Capacity of Rectangular Footings on Geogrid-Reinforced Sand.” Journal of Geotechnical Engineering 122, no. 4 (April 1996): 326–327. doi:10.1061/(asce)0733-9410(1996)122:4(326).

Ghazavi, Mahmoud, and Arash Alimardani Lavasan. “Interference Effect of Shallow Foundations Constructed on Sand Reinforced with Geosynthetics.” Geotextiles and Geomembranes 26, no. 5 (October 2008): 404–415. doi:10.1016/j.geotexmem.2008.02.003.

Golder, H.Q, Fellenius, W, Kogler, F, Meischeider, H, Krey, H, and Prandtl, M. “The Ultimate Bearing Pressure of Rectangular Footings.” Journal of the Institution of Civil Engineers 17, no. 2 (December 1941): 161–174. doi:10.1680/ijoti.1941.13728.

Hegde, A., and T.G. Sitharam. “3-Dimensional Numerical Modelling of Geocell Reinforced Sand Beds.” Geotextiles and Geomembranes 43, no. 2 (April 2015): 171–181. doi:10.1016/ j.geotexmem.2014.11.009.

Hegde, A., and T.G. Sitharam. “Experimental and Numerical Studies on Protection of Buried Pipelines and Underground Utilities Using Geocells.” Geotextiles and Geomembranes 43, no. 5 (October 2015): 372–381. doi:10.1016/j.geotexmem.2015.04.010.

Hegde, A., and T.G. Sitharam. “Experiment and 3D-Numerical Studies on Soft Clay Bed Reinforced with Different Types of Cellular Confinement Systems.” Transportation Geotechnics 10 (March 2017): 73–84. doi: 10.1016/j.trgeo.2017.01.001.

Hettler, A., and Gudehus, G. “Influence of the Foundation Width on the Bearing Capacity Factor.” Soils and Foundations 28, no. 4 (1988): 81–92. doi:10.3208/sandf1972.28.4_81.

Kusakabe, O. “Foundations.” Geotechnical Centrifuge Technology (n.d.): 118–167. doi:10.4324/ 9780203210536_chapter_6.

Lavasan, Arash Alimardani, and Mahmoud Ghazavi. “Behavior of Closely Spaced Square and Circular Footings on Reinforced Sand.” Soils and Foundations 52, no. 1 (February 2012): 160–167. doi:10.1016/j.sandf.2012.01.006.

Lavasan, Arash Alimardani, Mahmoud Ghazavi, and Tom Schanz. “Analysis of Interfering Circular Footings on Reinforced Soil by Physical and Numerical Approaches Considering Strain-Dependent Stiffness.” International Journal of Geomechanics 17, no. 11 (November 2017): 04017096. doi:10.1061/(asce)gm.1943-5622.0000992.

Oliaei, Mohammad, and Saeed Kouzegaran. “Efficiency of Cellular Geosynthetics for Foundation Reinforcement.” Geotextiles and Geomembranes 45, no. 2 (April 2017): 11–22. doi:10.1016/ j.geotexmem.2016.11.001.

Shadmand, A., M. Ghazavi, and N. Ganjian. “Load-Settlement Characteristics of Large-Scale Square Footing on Sand Reinforced with Opening Geocell Reinforcement.” Geotextiles and Geomembranes 46, no. 3 (June 2018): 319–326. doi:10.1016/j.geotexmem.2018.01.001.

Shiraishi, S. “Variation in Bearing Capacity Factors of Dense Sand Assessed by Model Loading Tests.” Soils and Foundations 30, no. 1 (1990): 17–26. doi:10.3208/sandf1972.30.17.

Sitharam, T.G., and S Sireesh. “Behavior of Embedded Footings Supported on Geogrid Cell Reinforced Foundation Beds.” Geotechnical Testing Journal 28, no. 5 (2005): 12751. doi:10.1520/gtj12751.

Terzaghi, Karl. “Theoretical Soil Mechanics” (January 1, 1943). doi:10.1002/9780470172766.

Ueno, Katsutoshi, Kinya Miura, and Yoshito Maeda. “Prediction of Ultimate Bearing Capacity of Surface Footings with Regard to Size Effects.” Soils and Foundations 38, no. 3 (1998): 165–178. doi:10.3208/sandf.38.3_165.


Full Text: PDF

DOI: 10.28991/cej-0309110

Refbacks

  • There are currently no refbacks.




Copyright (c) 2018 A. Shadmand, Mahmoud Ghazavi, Navid Ganjian

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
x
Message