Numerical and Physical Modeling of Soft Soil Slope Stabilized with Stone Columns

Document Type : Regular Paper

Authors

1 Ph.D. candidate, Department of Civil Engineering, University of Hormozgan, Bandar Abbas

2 Assistant Professor, Department of Civil Engineering, University of Hormozgan, Bandar Abbas, Iran

Abstract

There can be many reasons for engineers to place the footings near a slope such as leakage of suitable sites or architectural considerations. One of the approaches to increase the amount of bearing capacity, especially in soft soils, is adding stone columns to the soil. In this research, the behavior of a strip footing placed near a stone column reinforced clayey slope was investigated. For this purpose, some small-scale model tests were performed on a clayey slope reinforced with stone columns. The effects of the length of the stone column and the length of encasement on the footing were studied. Additionally, vertical encased stone columns in a group arrangement were investigated. Some numerical analyses were also performed using the Midas GTS NX finite element software, and the factor of safety was studied. Results show that the optimum length was equal to four times the diameter of stone columns. It was observed that by increasing the length of encasement, the bearing capacity of strip footing was also increased. The safety factor of slope showed an increase when stone columns were added to the slope, but the maximum influence on the factor of safety appeared when the stone column was in the upper middle of the slope.

Keywords

Main Subjects


[1] A. Ambily, S.R. Gandhi, (2007). Behavior of stone columns based on experimental and FEM analysis, Journal of geotechnical and geoenvironmental engineering, 133(4) 405-415. DOI: 10.1061/(ASCE)1090-0241(2007)133:4(405)
[2] J. Shahu, Y. Reddy, (2011). Clayey soil reinforced with stone column group: model tests and analyses, Journal of Geotechnical and Geoenvironmental Engineering, 137(12) 1265-1274. DOI: 10.1061/(ASCE)GT.1943-5606.0000552
[3] G. Kumar, M. Samanta, (2020). Experimental evaluation of stress concentration ratio of soft soil reinforced with stone column, Innovative Infrastructure Solutions, 5(1) 18. DOI: 10.1007/s41062-020-0264-6
[4] J. Nazariafshar, N. Mehrannia, F. Kalantary, N. Ganjian, (2019). Bearing capacity of group of stone columns with granular blankets, International Journal of Civil Engineering, 17(2) 253-263. DOI: 10.1007/s40999-017-0271-y
[5] J.M.O. Hughes, N.J. Withers, (1974). Reinforcing of soft cohesive soils with stone columns, International Journal of Rock Mechanics and Mining Sciences & Geomechanics, 11(11) A234.
[6] M. Ghazavi, J.N. Afshar, (2013). Bearing capacity of geosynthetic encased stone columns, Geotextiles and Geomembranes, 38 26-36. DOI: 10.1016/j.geotexmem.2013.04.003
[7] J. Gniel, A. Bouazza, (2009). Improvement of soft soils using geogrid encased stone columns, Geotextiles and Geomembranes, 27(3) 167-175. DOI: 10.1016/j.geotexmem.2008.11.001
[8] C. Cengiz, E. Güler, (2018). Seismic behavior of geosynthetic encased columns and ordinary stone columns, Geotextiles and Geomembranes, 46(1) 40-51. DOI: 10.1016/j.geotexmem.2017.10.001
[9] M. Miranda, A. Da Costa, J. Castro, C. Sagaseta, (2017). Influence of geotextile encasement on the behaviour of stone columns: Laboratory study, Geotextiles and Geomembranes, 45(1) 14-22. DOI: 10.1016/j.geotexmem.2016.08.004
[10] S. Nayak, M.P. Vibhoosha, A. Bhasi, (2019). Effect of Column Configuration on the Performance of Encased Stone Columns with Basal Geogrid Installed in Lithomargic Clay, International Journal of Geosynthetics and Ground Engineering, 5(4) 29. DOI: 10.1007/s40891-019-0181-y
[11] C. Yoo, Q. Abbas, (2020). Laboratory investigation of the behavior of a geosynthetic encased stone column in sand under cyclic loading, Geotextiles and Geomembranes. DOI: 10.1016/j.geotexmem.2020.02.002
[12] Y.-S. Hong, C.-S. Wu, C.-M. Kou, C.-H. Chang, (2017). A numerical analysis of a fully penetrated encased granular column, Geotextiles and Geomembranes, 45(5) 391-405. DOI: 10.1016/j.geotexmem.2017.05.002
[13] A.J. Choobbasti, H. Pichka, (2014). Improvement of soft clay using installation of geosynthetic-encased stone columns: numerical study, Arabian Journal of Geosciences, 7(2) 597-607. DOI: 10.1007/s12517-012-0735-y
[14] J. Castro, (2017). Groups of encased stone columns: Influence of column length and arrangement, Geotextiles and Geomembranes, 45(2) 68-80. DOI: 10.1016/j.geotexmem.2016.12.001
[15] A. Ehsaniyamchi, M. Ghazavi, (2019). Short-term and long-term behavior of geosynthetic-reinforced stone columns, Soils and Foundations, 59(5) 1579-1590. DOI: 10.1016/j.sandf.2019.07.007
[16] M.A. Nav, R. Rahnavard, A. Noorzad, R. Napolitano, (2020) Numerical evaluation of the behavior of ordinary and reinforced stone columns, Structures, 25 481-490. DOI: 10.1016/j.istruc.2020.03.021
[17] M.S. Keskin, M. Laman, (2014). Experimental and numerical studies of strip footings on geogrid-reinforced sand slope, Arabian Journal for Science and Engineering, 39(3) 1607-1619. DOI: 10.1007/s13369-013-0795-7
[18] M.A. El Sawwaf, (2007). Behavior of strip footing on geogrid-reinforced sand over a soft clay slope, Geotextiles and Geomembranes, 25(1) 50-60. DOI: 10.1016/j.geotexmem.2006.06.001
[19] A. Sommers, B. Viswanadham, (2009). Centrifuge model tests on the behavior of strip footing on geotextile-reinforced slopes, Geotextiles and Geomembranes, 27(6) 497-505. DOI: 10.1016/j.geotexmem.2009.05.002
[20] S. Naeini, B.K. Rabe, E. Mahmoodi, (2012). Bearing capacity and settlement of strip footing on geosynthetic reinforced clayey slopes, Journal of Central South University, 19(4) 1116-1124. DOI: 10.1007/s11771-012-1117-z
[21] N. Hataf, A. Fatolahzadeh, (2019). An experimental and numerical study on the bearing capacity of circular and ring footings on rehabilitated sand slopes with geogrid, Journal of Rehabilitation in Civil Engineering, 7(1) 174-185. DOI: 10.22075/JRCE.2018.11576.1193
[22] X. Li, S. He, Y. Luo, Y. Wu, (2011). Numerical studies of the position of piles in slope stabilization, Geomechanics and Geoengineering, 6(3) 209-215. DOI: 10.1080/17486025.2011.578668
[23] M. Ashour, H. Ardalan, (2012). Analysis of pile stabilized slopes based on soil–pile interaction, Computers and Geotechnics, 39 85-97. DOI: 10.1016/j.compgeo.2011.09.001
[24] M. Esmaeili, M. Gharouni Nik, F. Khayyer, (2013). Static and Dynamic Analyses of Micropiles to Reinforce the High Railway Embankments on Loose Beds, Journal of Rehabilitation in Civil Engineering, 1(2) 80-89. DOI: 10.22075/JRCE.2013.11
[25] Z. Zhang, J. Han, G. Ye, (2014). Numerical investigation on factors for deep-seated slope stability of stone column-supported embankments over soft clay, Engineering Geology, 168 104-113. DOI: 10.1016/j.enggeo.2013.11.004
[26] J.-F. Chen, L.-Y. Li, J.-F. Xue, S.-Z. Feng, (2015). Failure mechanism of geosynthetic-encased stone columns in soft soils under embankment, Geotextiles and Geomembranes, 43(5) 424-431. DOI: 10.1016/j.geotexmem.2015.04.016
[27] G. Zheng, X. Yu, H. Zhou, S. Wang, J. Zhao, X. He, X. Yang, (2020). Stability analysis of stone column-supported and geosynthetic-reinforced embankments on soft ground, Geotextiles and Geomembranes. DOI: 10.1016/j.geotexmem.2019.12.006
[28] M. Ghazavi, A. Shahmandi, (2008). Analytical Static Stability Analysis of Slopes Reinforced by Stone, The 12th International Conference of International Association for Computer Methods and Advances in Geomechanics (IACMAG), India, 3530-3537.
[29] M. Vekli, M. Aytekin, S.B. Ikizler, Ü. Çalik, (2012). Experimental and numerical investigation of slope stabilization by stone columns, Natural hazards, 64(1) 797-820. DOI: 10.1007/s11069-012-0272-8
[30] M. Hajiazizi, E. Nemati, M. Nasiri, M. Bavali, M. Sharifipur, (2012). Optimal Location of Stone Column in Stabilization of Sand Slope: An Experimental and 3D Numerical Investigation, Scientia Iranica. DOI: 10.24200/SCI.2018.20331
[31] E. Raee, N. Hataf, K. Barkhordari, A. Ghahramani, (2018). The Effect of Rigidity of Reinforced Stone Columns on Bearing Capacity of Strip Footings on the Stabilized Slopes, International Journal of Civil Engineering, 1-13. DOI: 10.1007/s40999-018-0291-2
[32] E. Naderi, A. Asakereh, M. Dehghani, (2018). Bearing Capacity of Strip Footing on Clay Slope Reinforced with Stone Columns, Arabian Journal for Science and Engineering, 43(10) 5559-5572. DOI: 10.1007/s13369-018-3231-1
[33] M. Nasiri, M. Hajiazizi, (2019). An experimental and numerical investigation of reinforced slope using geotextile encased stone column, International Journal of Geotechnical Engineering, 1-10. DOI: 10.1080/19386362.2019.1651029
[34] A.S.f.T.a. Materials, ASTM, (1984). American Society for Testing.
[35] S.K. Dash, M.C. Bora, (2013). Influence of geosynthetic encasement on the performance of stone columns floating in soft clay, Canadian Geotechnical Journal, 50(7) 754-765. DOI: 10.1139/cgj-2012-0437
[36] D.M. Wood, W. Hu, D.F.T. Nash, (2000). Group effects in stone column foundations: model tests, Géotechnique, 50(6) 689-698. DOI: 10.1680/geot.2000.50.6.689
[37] R. Barksdale, R. Bachus, (1983). Design and Construction of Stone Columns Volume II, Appendixes, Federal Highway Administration Washington, DC, USA.
[38] M. Hasan, N. Samadhiya, (2017). Performance of geosynthetic-reinforced granular piles in soft clays: Model tests and numerical analysis, Computers and Geotechnics, 87 178-187. DOI: 10.1016/j.compgeo.2017.02.016
[39] MIDAS/GTS NX. manual, (2016). Modeling, Integrated Design & Analysis Software. A geotechnical and tunnel analysis system.
[40] USACE, (1990). Settlement Analysis, Engineer Manual EM 1110‐1‐1904.
[41] P. Debnath, A.K. Dey, (2017). Bearing capacity of geogrid reinforced sand over encased stone columns in soft clay, Geotextiles and Geomembranes, 45(6) 653-664. DOI: 10.1016/j.geotexmem.2017.08.006
[42] S.-W. Sun, W. Wang, F. Zhao, (2014). Three-dimensional stability analysis of a homogeneous slope reinforced with micropiles, Mathematical Problems in Engineering, 2014 1-11. DOI: 10.1155/2014/864017
[43] P. Paresh, S. Vasanwala, (2012). Numerical analysis of slope reinforced with stone column, Int. journal of civil, structural, environmental and infrastructure engineering research and development, 2(2) 7.
[44] W. Wei, Y. Cheng, (2009). Strength reduction analysis for slope reinforced with one row of piles, Computers and Geotechnics, 36(7) 1176-1185. DOI: 10.1016/j.compgeo.2009.05.004