Numerical Analyses on Cellular Mattress–Reinforced Fly Ash Beds Overlying Soft Clay
Publication: International Journal of Geomechanics
Volume 17, Issue 4
Abstract
This paper presents the results of large-scale numerical modeling of cellular mattress–reinforced fly ash beds overlying soft clay using a finite-element program. The cellular mattress was a honeycomb structure consisting of interconnected multiple circular cells. The influence of the height, diameter, and tensile stiffness of the cell and the width of the entire mattress on the pressure-settlement response of footing, surface deformation during footing settlement, and mobilization of hoop tension in the cell walls are illustrated. Results from the numerical analyses indicate an improvement in footing capacity of approximately1.4 times greater over fly ash bed by inclusion of a single geotextile separator representing jute geotextile in between the fly ash bed and underlying clay. The cellular mattress–fly ash composite bed produced an approximately sevenfold increment in the footing capacity compared with the unreinforced fly ash bed both in presence of the jute separator. The mattress-reinforced beds produced better footing capacity with an increase in the height and width of the mattress and the tensile stiffness of the cell wall. It is satisfactory to acquire the optimization for the height and width of mattress and the tensile stiffness of the cell wall. For a particular mattress width and height, the footing capacity increased with a reduction in the cell diameter. The cell at the mattress center mobilized maximum hoop tension that was lesser in the cells successively toward the mattress periphery. Also, more hoop tension was mobilized with an increase in the tensile stiffness of cell wall. Small-scale finite-element models were created using the same material models and properties as those used for the large-scale modeling to validate the program with laboratory small-scale model tests comprising the same model conditions. The finite-element results were found to be in good agreement with the experimental results.
Get full access to this article
View all available purchase options and get full access to this article.
References
ASTM. (2007). “Standard test method for unconsolidated-undrained triaxial compression test on cohesive soils.” D2850-03a, West Conshohocken, PA.
ASTM. (2010a). “Standard test methods for specific gravity of soil solids by water pycnometer.” D854, West Conshohocken, PA.
ASTM. (2010b). “Standard test method for measuring mass per unit area of geotextiles.” D5261, West Conshohocken, PA.
ASTM. (2011a). “Standard practice for classification of soil for engineering purpose (Unified Soil Classification System).” D2487, West Conshohocken, PA.
ASTM. (2011b). “Standard test method for consolidated drained triaxial compression test for soils.” D7181, West Conshohocken, PA.
ASTM. (2011c). “Standard test method for tensile properties of geotextiles by the wide-width strip method.” D4595, West Conshohocken, PA.
ASTM. (2011d). “Standard test method for breaking force and elongation of textile fabrics (strip method).” D5035, West Conshohocken, PA.
ASTM. (2012a). “Standard test methods for laboratory compaction characteristics of soil using standard effort (12 400-lbf/ft3 (600 kN-m/m3)).” D698, West Conshohocken, PA.
ASTM. (2012b). “Standard test method for measuring nominal thickness of geosynthetics.” D5199, West Conshohocken, PA.
ASTM. (2012c). “Standard test method for determining apparent opening size of a geotextile.” D4751, West Conshohocken, PA.
Bathurst, R. J., and Karpurapu, R. (1993). “Large-scale triaxial compression testing of geocell-reinforced granular soils.” Geotech. Test. J., 16(3), 296–303.
Bathurst, R. J., and Knight, M. A. (1998). “Analysis of geocell reinforced soil covers over large span conduits.” Comput. Geotech., 22(3/4), 205–219.
Baykal, G., Edinçliler, A., and Saygili, A. (2004). “Highway embankment construction using fly ash in cold regions.” Resour. Conserv. Recycl., 42(3), 209–222.
Bourdeau, P. L. (1989). “Modeling of membrane action in a two-layer reinforced soil system.” Comput. Geotech., 7(1–2), 19–36.
Bush, D. I., Jenner, C. G., and Basset, R. H. (1990). “The design and construction of geocell foundation mattress supporting embankments over soft ground.” Geotext. Geomembr., 9(1), 83–98.
Chummar, A. V. (1972). “Bearing capacity theory from experimental results.” J. Soil Mech. Found. Div., 98(12), 1311–1324.
Cowland, J. W., and Wong, S. C. K. (1993). “Performance of a road embankment on soft clay supported on a geocell mattress foundation.” Geotext. Geomembr., 12(8), 687–705.
Dash, S. K., Krishnaswamy, N. R., and Rajagopal, K. (2001). “Bearing capacity of strip footings supported on geocell-reinforced sand.” Geotext. Geomembr., 19(4), 235–256.
Dash, S. K., Sireesh, S., and Sitharam, T. G. (2003a). “Behaviour of geocell-reinforced sand beds under circular footing.” Ground Improv., 7(3), 111–115.
Dash, S. K., Sireesh, S., and Sitharam, T. G. (2003b). “Model studies on circular footing supported on geocell reinforced sand underlain by soft clay.” Geotext. Geomembr., 21(4), 197–219.
de Garidel, R., and Morel, G. (1986). “New soil strengthening techniques by textile elements for low volume roads.” Proc., 3rd Int. Conf. on Geotextiles, Balkema, Rotterdam, Netherlands, 1027–1032.
Dong, P. (2007). “The application of geocell mattress in Qin-Yin highway.” Transport. World, 14(10), 96–98.
Dutta, S., and Mandal, J. N. (2015). “Model studies on geocell-reinforced fly ash bed overlying soft clay.” J. Mater. Civ. Eng., 04015091.
Emersleben, A., and Meyer, N. (2010). “Verification of the load transfer mechanism of geocell reinforced soil in large scale model tests and different in situ test fields.” Proc., GeoFlorida 2010: Advances in Analysis, Modeling & Design, ASCE, Reston, VA, 1670–1679.
Ghosh, A., and Dey, U. (2009). “Bearing ratio of reinforced fly ash overlying soft soil and deformation modulus of fly ash.” Geotext. Geomembr., 27(4), 313–320.
Ghosh, A., and Subbarao, C. (2006). “Tensile strength bearing ratio and slake durability of class F fly ash stabilized with lime and gypsum.” J. Mater. Civ. Eng., 18–27.
Ghosh, C., and Madhav, M. R. (1994). “Reinforced granular fill-soft soil system: confinement effect.” Geotext. Geomembr., 13(11), 727–741.
Ghosh, R. K., Chadda, L. R., Pant, C. S., and Sharma, R. K. (1973). “Stabilization of alluvial soil with lime and fly ash.” Indian Road Congr., 35(2), 489–511.
Han, J., Yang, X., Leshchinsky, D., and Parsons, R. L. (2008). “Behavior of geocell-reinforced sand under a vertical load.” Transportation Research Record, 2045, 95–101.
Hegde, A., and Sitharam, T. G. (2013). “Experimental and numerical studies on footings supported on geocell reinforced sand and clay beds.” Int. J. Geotech. Eng., 7(4), 346–354.
Hegde, A., and Sitharam, T. G. (2015). “3-dimensional numerical modeling of geocell reinforced sand beds.” Geotext. Geomembr., 43(2), 171–181.
Hegde, A. M., and Sitharam, T. G. (2014). “Effect of infill materials on the performance of geocell reinforced soft clay beds.” Geomech. Geoeng., 10(3), 163–173.
Kim, B., Prezzi, M., and Salgado, R. (2005). “Geotechnical properties of fly and bottom ash mixtures for use in highway embankments.” J. Geotech. Geoenviron. Eng., 914–924.
Leshchinsky, B., and Ling, H. (2013a). “Effects of geocell confinement on strength and deformation behavior of gravel.” J. Geotech. Geoenviron. Eng., 340–352.
Leshchinsky, B., and Ling, H. (2013b). “Numerical modeling of behavior of railway ballasted structure with geocell confinement.” Geotext. Geomembr., 36, 33–43.
Li, M. T. (2000). “An analysis of the stability of roads and bridges in the mined-up region of the Taigu highway and the treating scheme.” J. Chongqing Jiaotong Inst., 19(3), 85–87.
Madhavi Latha, G., Rajagopal, K., and Krishnaswamy, N. R. (2006). “Experimental and theoretical investigations on geocell-supported embankments.” Int. J. Geomech., 30–35.
Madhavi Latha, G., and Somwanshi, A. (2009). “Effect of reinforcement form on the bearing capacity of square footings on sand.” Geotext. Geomembr., 27(6), 409–422.
Mehdipour, I., Ghazavi, M., and Moayed, R. Z. (2013). “Numerical study on stability analysis of geocell reinforced slopes by considering the bending effect.” Geotext. Geomembr, 37, 23–34.
Mhaiskar, S. Y., and Mandal, J. N. (1996). “Investigation on soft clay subgrade strengthening using geocells.” Constr. Build. Mater., 10(4), 281–286.
Moghaddas Tafreshi, S. N., and Dawson, A. R. (2012). “A comparison of static and cyclic loading responses of foundations on geocell-reinforced sand.” Geotext. Geomembr., 32, 55–68.
PLAXIS 3D [Computer software]. Plaxis bv, Delft, Netherlands.
Pokharel, S., et al. (2011). “Accelerated pavement testing of geocell-reinforced unpaved roads over weak subgrade.” Transportation Research Record, 2204, 67–75.
Saride, S., Gowrisetti, S., Sitharam, T. G., and Puppala, A. J. (2009). “Numerical simulations of geocell-reinforced sand and clay.” Ground Improv., 162(4), 185–198.
Saride, S., Vedpathak, S., and Rayabharapu, V. (2014). “Elasto-plastic behavior of jute-geocell reinforced sand subgrade.” Geo-Congress 2014, GSP 234, ASCE, Reston, VA, 2911–2920.
Satyanarayana Reddy, C. N. V., and Rama Moorthy, N. V. (2004). “Geo-technical investigations into flexible pavement design over a clay subgrade.” Proc., Indian Geotechnical Conf., Indian Geotechnical Society, New Delhi, India, 514–517.
Selig, E. T., and McKee, K. E. (1961). “Static and dynamic behaviour of small footings.” J. Soil Mech. Found. Div., 87(SM6), 29–47.
Shukla, S. K., and Chandra, S. A. (1994). “A study of settlement response of a geosynthetic reinforced compressible granular fill-soft soil system.” Geotext. Geomembr., 13(9), 627–639.
Sireesh, S., Sitharam, T. G., and Dash, S. K. (2009). “Bearing capacity of circular footing on geocell-sand mattress overlying clay bed with void.” Geotext. Geomembr., 27(2), 89–98.
Sitharam, T. G., and Sireesh, S. (2005). “Behaviour of embedded footings supported on geocell reinforced foundation beds.” Geotech. Test. J., 28(5), 452–463.
Sitharam, T. G., Sireesh, S., and Dash, S. K. (2005). “Model studies of a circular footing supported on geocell-reinforced clay.” Can. Geotech. J., 42(2), 693–703.
Sitharam, T. G., Sireesh, S., and Dash, S. K. (2007). “Performance of surface footing on geocell-reinforced soft clay beds.” Geotech. Geol. Eng., 25(5), 509–524.
Waterman, D. (2006). “Structural elements in PLAXIS.” PLAXIS Finite Element Code for Soil and Rock Analyses, Plaxis bv, Delft, Netherlands.
Webster, S. L. (1979). “Investigation of beach sand trafficability enhancement using sand-grid confinement and membrane reinforcement concepts.” Rep. GL-79-20(1), U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS.
Weng, B. S., and Luo, Q. (2006). “Geotechnique economical analysis of the geocell reinforcement in exist railroad embankment.” Subgrade Eng., 24(3), 56–58.
Xie, Y. L., Yu, Y. H., and Yang, X. H. (2004). “Application study of treating differential settlement of subgrade with geocell.” China J. Highway Transp., 17(4), 7–10.
Yang, X., Han, J., Parsons, R. L., and Leshchinsky, D. (2010). “Three-dimensional numerical modeling of single geocell-reinforced sand.” Front. Archit. Civ. Eng. China, 4(2), 233–240.
Yang, X. H., Dai, T. D., and Xu, X. Z. (2005). “Geocell application in reinforcing soft subgrade of railway.” J. Traffic Transp. Eng., 5(2), 42–46.
Yin, J. H. (1997a). “Modeling geosynthetic-reinforced granular base over soft soil.” Geosynth. Int. J., 4(2), 168–185.
Yin, J. H. (1997b). “A non-linear model for geosynthetic-reinforced granular fill over soft soil.” Geosynth. Int. J., 4(5), 523–537.
Yoon, Y. W., Heo, S. B., and Kim, K. S. (2008). “Geotechnical performance of waste tires for soil reinforcement from chamber tests.” Geotext. Geomembr., 26(1), 100–107.
Zhang, L., Zhao, M., Zou, X., and Zhao, H. (2009). “Deformation analysis of geocell reinforcement using Winkler model.” Comput. Geotech., 36(6), 977–983.
Zhang, Z. G., and Liu, D. X. (2004). “Settlement calculation of the soft foundation treated by geocell with finite bean method.” Gansu Hydrotech. Hydroelectrics, 40(2), 136–137.
Zhou, H., and Wen, X. (2008). “Model studies on geogrid or geocell-reinforced sand cushion on soft soil.” Geotext. Geomembr., 26(3), 231–238.
Information & Authors
Information
Published In
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Dec 15, 2015
Accepted: Jun 24, 2016
Published online: Sep 1, 2016
Discussion open until: Feb 1, 2017
Published in print: Apr 1, 2017
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.