Geomechanics and Engineering

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Small- and large-scale analysis of bearing capacity and load-settlement behavior of rock-soil slopes reinforced with geogrid-box method

  • Received : 2018.10.30
  • Accepted : 2019.06.07
  • Published : 2019.06.30
⟨ Previous Next ⟩

Abstract

This paper presents an investigation on bearing capacity, load-settlement behavior and safety factor of rock-soil slopes reinforced using geogrid-box method (GBM). To this end, small-scale laboratory studies were carried out to study the load-settlement response of a circular footing resting on unreinforced and reinforced rock-soil slopes. Several parameters including unit weight of rock-soil materials (loose- and dense-packing modes), slope height, location of footing relative to the slope crest, and geogrid tensile strength were studied. A series of finite element analysis were conducted using ABAQUS software to predict the bearing capacity behavior of slopes. Limit equilibrium and finite element analysis were also performed using commercially available software SLIDE and ABAQUS, respectively to calculate the safety factor. It was found that stabilization of rock-soil slopes using GBM significantly improves the bearing capacity and settlement behavior of slopes. It was established that, the displacement contours in the dense-packing mode distribute in a broader and deeper area as compared with the loose-packing mode, which results in higher ultimate bearing load. Moreover, it was found that in the loose-packing mode an increase in the vertical pressure load is accompanied with an increase in the soil settlement, while in the dense-packing mode the load-settlement curves show a pronounced peak. Comparison of bearing capacity ratios for the dense- and loose-packing modes demonstrated that the maximum benefit of GBM is achieved for rock-soil slopes in loose-packing mode. It was also found that by increasing the slope height, both the initial stiffness and the bearing load decreases. The results indicated a significant increase in the ultimate bearing load as the distance of the footing to the slope crest increases. For all the cases, a good agreement between the laboratory and numerical results was observed.

Keywords

References

  1. Abhishek, S., Rajyalakshmi, K. and Madhav, M. (2015), "Bearing capacity of strip footing on reinforced foundation bed over soft ground with granular trench", Ind. Geotech. J., 45(3), 304-317. https://doi.org/10.1007/s40098-014-0138-y.
  2. Alamshahi, S. and Hataf, N. (2009), "Bearing capacity of strip footings on sand slopes reinforced with geogrid and grid-anchor", Geotext. Geomembr., 27(3), 217-226. https://doi.org/10.1016/j.geotexmem.2008.11.011.
  3. Alejano, L., Pons, B., Bastante, F., Alonso, E. and Stockhausen, H. (2007), "Slope geometry design as a means for controlling rockfalls in quarries", Int. J. Rock Mech. Min. Sci., 44(6), 903-921. https://doi.org/10.1016/j.ijrmms.2007.02.001.
  4. Alkasawneh, W., Malkawi, A.I.H., Nusairat, J.H. and Albataineh, N. (2008), "A comparative study of various commercially available programs in slope stability analysis", Comput. Geotech., 35(3), 428-435. https://doi.org/10.1016/j.compgeo.2007.06.009.
  5. Ashtiani, M., Ghalandarzadeh, A. and Towhata, I. (2015), "Centrifuge modeling of shallow embedded foundations subjected to reverse fault rupture", Can. Geotech. J., 53(3), 505-519. https://doi.org/10.1139/cgj-2014-0444.
  6. Ausilio, E., Conte, E. and Dente, G. (2001), "Stability analysis of slopes reinforced with piles", Comput. Geotech., 28(8), 591-611. https://doi.org/10.1016/S0266-352X(01)00013-1.
  7. Berry, D.S. (1935), Stability of Granular Mixtures, University of Michigan, Michigan, U.S.A.
  8. Bishop, A.W. (1955), "The use of the slip circle in the stability analysis of slopes", Geotechnique, 5(1), 7-17. https://doi.org/10.1680/geot.1955.5.1.7
  9. Bouassida, M., Jellali, B. and Lyamin, A. (2014), "Ultimate bearing capacity of a strip footing on ground reinforced by a trench", Int. J. Geomech., 15(3), 06014021. https://doi.org/10.1061/(ASCE)GM.1943-5622.0000418.
  10. Cerato, A.B. and Lutenegger, A.J. (2007), "Scale effects of shallow foundation bearing capacity on granular material", J. Geotech. Geoenviron. Eng., 133(10), 1192-1202. https://doi.org/10.1061/(ASCE)1090-0241(2007)133:10(1192).
  11. Chung, W. and Cascante, G. (2007), "Experimental and numerical study of soil-reinforcement effects on the low-strain stiffness and bearing capacity of shallow foundations", Geotech. Geol. Eng., 25(3), 265-281. https://doi.org/10.1007/s10706-006-9109-0.
  12. Conte, E. and Troncone, A. (2018), "A performance-based method for the design of drainage trenches used to stabilize slopes", Eng. Geol., 239, 158-166. https://doi.org/10.1016/j.enggeo.2018.03.017.
  13. Demir, A., Yildiz, A., Laman, M. and Ornek, M. (2014), "Experimental and numerical analyses of circular footing on geogrid-reinforced granular fill underlain by soft clay", Acta Geotechnica, 9(4), 711-723. https://doi.org/10.1007/s11440-013-0207-x.
  14. El Sawwaf, M. (2010), "Experimental and numerical study of strip footing supported on stabilized sand slope", Geotech. Geol. Eng., 28(4), 311-323. https://doi.org/10.1007/s10706-009-9293-9.
  15. El Sawwaf, M.A. (2007), "Behavior of strip footing on geogrid-reinforced sand over a soft clay slope", Geotext. Geomembranes, 25(1), 50-60. https://doi.org/10.1016/j.geotexmem.2006.06.001.
  16. Fahimifar, A., Abdolmaleki, A. and Soltani, P. (2014), "Stabilization of rock slopes using geogrid boxes", Arab. J. Geosci., 7(2), 609-621. https://doi.org/10.1007/s12517-012-0755-7.
  17. Fahimifar, A. and Soroush, H. (2005), "A theoretical approach for analysis of the interaction between grouted rockbolts and rock masses", Tunn. Undergr. Sp. Technol., 20(4), 333-343. https://doi.org/10.1016/j.tust.2004.12.005.
  18. Fattah, M., Shlash, K. and Mohammed, H. (2014), "Bearing capacity of rectangular footing on sandy soil bounded by a wall", Arab. J. Sci. Eng., 39(11). https://doi.org/10.1007/s13369-014-1353-7.
  19. Feng, S.J., Chen, Z.W., Chen, H.X., Zheng, Q.T. and Liu, R. (2018), "Slope stability of landfills considering leachate recirculation using vertical wells", Eng. Geol., 241, 76-85. https://doi.org/10.1016/j.enggeo.2018.05.013.
  20. Gurocak, Z., Alemdag, S. and Zaman, M.M. (2008), "Rock slope stability and excavatability assessment of rocks at the Kapikaya Dam Site, Turkey", Eng. Geol., 96(1-2), 17-27. https://doi.org/10.1016/j.enggeo.2007.08.005.
  21. Hataf, N. and Sadr, A. (2015), "Experimental, numerical and analytical study on conventional and innovative Grid-Anchor system in the pull-out test", Geomech. Geoeng., 10(3), 182-193. https://doi.org/10.1080/17486025.2014.933893.
  22. Hou, J., Zhang, M.X., Dai, Z.H., Li, J.Z. and Zeng, F.F. (2017), "Bearing capacity of strip foundations in horizontal-vertical reinforced soils", Geotext. Geomembranes, 45(1), 29-34. https://doi.org/10.1016/j.geotexmem.2016.07.001.
  23. Huang, M. and Jia, C.Q. (2003), "Strength reduction FEM in stability analysis of soil Slopes subjected to transient unsaturated seepage", Comput. Geotech., 36(1-2), 93-101. https://doi.org/10.1016/j.compgeo.2008.03.006.
  24. Janbu, N. (1954), Application of Composite Slip Surface for Stability Analysis, Stockholm, Sweden.
  25. Keskin, M.S. and Laman, M. (2014), "Experimental and numerical studies of strip footings on geogrid-reinforced sand slope", Arab. J. Sci. Eng., 39(3), 1607-1619. https://doi.org/10.1007/s13369-013-0795-7.
  26. Kumar, J. and Khatri, V. (2008), "Effect of footing width on bearing capacity factor $N_{\gamma}$ for smooth strip footings", J. Geotech. Geoenviron. Eng., 134(9), 1299-1310. https://doi.org/10.1061/(ASCE)1090-0241(2008)134:9(1299).
  27. Kusakabe, O., Yamaguchi, H. and Morikage, A. (1991), "Experiment and analysis on the scale effect of $N_{\gamma}$ for circular and rectangular footings", Proceedings of the International Conference on Centrifuge, Boulder, Colorado, U.S.A.
  28. Ladd, R. (1978), "Preparing test specimens using undercompaction", Geotech. Test. J., 1(1), 16-23. https://doi.org/10.1520/GTJ10364J.
  29. Mahboubi, A., Aminpour, M. and Noorzad, A. (2008), "Conventional and advanced numerical methods of rock slope stability analysis, A comparison study, Gotvand Dam Right Abutment (Iran) case study", Proceedings of the 12th International Conference of International Association for Computer Methods and Advances in Geomechanics (IACMAG), Goa, India, October.
  30. Meyerhof, G.G. (1963), "Some recent research on the bearing capacity of foundations", Can. Geotech. J., 1(1), 16-26. https://doi.org/10.1139/t63-003.
  31. Moradi, G., Abdolmaleki, A., Soltani, P. and Ahmadvand, M. (2018), "A laboratory and numerical study on the effect of geogrid-box method on bearing capacity of rock-soil slopes", Geomech. Eng., 14(9), 345-354. https://doi.org/10.12989/gae.2018.14.4.345.
  32. Mosallanezhad, M., Hataf, N. and Ghahramani, A. (2008), "Experimental study of bearing capacity of granular soils, reinforced with innovative grid-anchor system", Geotech. Geol. Eng., 26(3), 299-312. https://doi.org/10.1007/s10706-007-9166-z
  33. Naeini, S., Rabe, B.K. and Mahmoodi, E. (2012), "Bearing capacity and settlement of strip footing on geosynthetic reinforced clayey slopes", J. Central South Univ., 19(4), 1116-1124. https://doi.org/10.1007/s11771-012-1117-z.
  34. Nareeman, B.J. (2012), "A study on the scale effect on bearing capacity and settlement of shallow foundations", Int. J. Eng. Technol., 2(3), 480-488.
  35. Prasad, B.D., Hariprasad, C. and Umashankar, B. (2016), "Load-settlement response of square footing on geogrid reinforced layered granular beds", Int. J. Geosynth. Ground Eng., 2(4), 36. https://doi.org/10.1007/s40891-016-0070-6.
  36. Puzrin, A.M., Gray, T.E. and Hill, A.J. (2015), "Significance of the actual nonlinear slope geometry for catastrophic failure in submarine landslides", Proc. R. Soc. A Math. Phys. Eng. Sci., 471(2175), 20140772. https://doi.org/10.1098/rspa.2014.0772.
  37. Ranjbarnia, M., Fahimifar, A. and Oreste, P. (2015), "Practical method for the design of pretensioned fully grouted rockbolts in tunnels", Int. J. Geomech., 16(1), 04015012. https://doi.org/10.1061/(ASCE)GM.1943-5622.0000464.
  38. Saleh Ahmadi, M. and Moghadam, P.N. (2017), "Effect of geogrid aperture size and soil particle size on geogrid-soil interaction under pull-out loading", J. Text. Polymers, 5(1), 25-30.
  39. Spencer, E. (1967), "A method of analysis of the stability of embankments assuming parallel interslice forces", Geotechnique, 17, 11-26. https://doi.org/10.1680/geot.1967.17.1.11
  40. Srbulov, M. (2001), "Analyses of stability of geogrid reinforced steep slopes and retaining walls", Comput. Geotech., 28(4), 255-268. https://doi.org/10.1016/S0266-352X(00)00032-X.
  41. Tavakoli, M.G., 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. https://doi.org/10.1016/j.geotexmem.2016.06.006
  42. Tavangar, Y. and Shooshpasha, I. (2016), "Experimental and numerical study of bearing capacity and effect of specimen size on uniform sand with medium density, reinforced with nonwoven geotextile", Arab. J. Sci. Eng., 41(10), 4127-4137. https://doi.org/10.1007/s13369-016-2101-y.
  43. Touze-Foltz, N., Bannour, H., Barral, C. and Stoltz, G. (2016), "A review of the performance of geosynthetics for environmental protection", Geotext. Geomembranes, 44(5), 656-672. https://doi.org/10.1016/j.geotexmem.2016.05.008.
  44. Turker, E., Sadoglu, E., Cure, E. and Uzuner, B.A. (2014), "Bearing capacity of eccentrically loaded strip footings close to geotextile-reinforced sand slope", Can. Geotech. J., 51(8), 884-895. https://doi.org/10.1139/cgj-2014-0055.
  45. Ukritchon, B., Whittle, A.J. and Klangvijit, C. (2003), "Calculations of bearing capacity factor $N_{\gamma}$ using numerical limit analyses", J. Geotech. Geoenviron. Eng., 129(5), 468-474. https://doi.org/10.1061/(ASCE)1090-0241(2003)129:6(468).
  46. Unnikrishnan, N. and Rajan, S. (2012), "Bearing capacity of strip footings on geosynthetic encapsulated granular trenches", Proceedings of the International Conference on Ground Improvement and Ground Control, Wollongong, Australia, October-November.
  47. Viswanadham, B.V.S. and Konig, D. (2009), "Centrifuge modeling of geotextile-reinforced slopes subjected to differential settlements", Geotext. Geomembranes, 27(2), 77-88. https://doi.org/10.1016/j.geotexmem.2008.09.008.
  48. Won, J., You, K., Jeong, S. and Kim, S. (2005), "Coupled effects in stability analysis of pile-slope systems", Comput. Geotech., 32(4), 304-315. https://doi.org/10.1016/j.compgeo.2005.02.006.
  49. Xiao, S., Feng, W. and Zhang, J. (2010), "Analysis of the effects of slope geometry on the dynamic response of a near-field mountain from the Wenchuan Earthquake", J. Mountain Sci., 7(4), 353-360. https://doi.org/10.1007/s11629-010-2055-6.
  50. Xu, D.S. and Yin, J.H. (2016), "Analysis of excavation induced stress distributions of GFRP anchors in a soil slope using distributed fiber optic sensors", Eng. Geol., 213, 55-63. https://doi.org/10.1016/j.enggeo.2016.08.011.
  51. Yoo, C. (2001), "Laboratory investigation of bearing capacity behavior of strip footing on geogrid-reinforced sand slope", Geotext. Geomembranes, 19(5), 279-298. https://doi.org/10.1016/S0266-1144(01)00009-7.
  52. Zhang, X. and Zhou, X. (2018), "Analysis of the numerical stability of soil slope using virtual-bond general particle dynamics", Eng. Geol., 243, 101-110. https://doi.org/10.1016/j.enggeo.2018.06.018.
  53. Zhu, F., Clark, J.I. and Phillips, R. (2001), "Scale effect of strip and circular footings resting on dense sand", J. Geotech. Geoenviron. Eng., 127(7), 613-621. https://doi.org/10.1061/(ASCE)1090-0241(2001)127:7(613).

Cited by

  1. Numerical Analysis of Bearing Capacity of Strip Footing Built on Geogrid-Reinforced Sand Slope Over Soft Clay Layer (revised version 3) vol.45, pp.10, 2019, https://doi.org/10.1007/s13369-020-04646-9