Improvement of Soft Soil Using Linear Distributed Floating Stone Columns under Foundation Subjected to Static and Cyclic Loading

Mahdi O Karkush, Anwar Jabbar


A stone column is one of the soil improvement methods that are mainly used for improving the geotechnical behavior of soft soils. For deep improvement of soft soil, the floating stone columns are considered the best and effective economically which provide lateral confinement and drainage and longitudinal skin friction. In this study, six tests were carried out on the natural soft soil of undrained shear strength of 5.5 kPa improved by single and two linear distributed floating stone columns. The stone column dimensions are 30 mm in diameter and 180 mm in length and the stone column material is sand of high internal friction angle of 48°. The natural and improved soil samples are tested under isolated raft foundation of dimensions 120×120 mm subjected to vertical static and cyclic loading of frequency 2Hz and continued for 50 seconds. The results showed a significant improvement in soil bearing capacity when reinforced with stone columns despite the small area replacement ratio, where the bearing capacity of improved soil increased by 120 to 145%. The compressibility of improved soil decreased by 57 to 86% in comparison with that of natural soft soil. Also, the floating stone columns reduced the porewater pressure, where the stone columns considered efficient in providing short drainage pathways. This can be one of the reasons why soil reinforced with floating stone columns hold higher cyclic and static stresses regardless the end bearing of stone columns.


Floating; Stone Column; Soft Soil; Axial Loading; Cyclic Loading.


Abbawi, Z.W. “Evaluation of improvement techniques for ballasted railway track model resting on soft clay” Ph. D. Thesis, Building and Construction Engineering Department, University of Technology, Baghdad, Iraq (2010).

Malarvizhi, S. N., and K. Ilamparuthi. "Load versus settlement of clay bed stabilized with stone and reinforced stone columns." In 3rd Asian Regional Conference on Geosynthetics, pp. 322-329. 2004.

Mitchell, John Michael, and Finlay M. Jardine. A guide to ground treatment. Vol. 573. London: CIRIA, 2002.

Verma, Shivani, Vikas Kumar, and Akash Priyadarshee. “An Experimental Test Study on Ring Footing Resting on Clay Bed Reinforced by Stone Column.” Innovative Infrastructure Solutions 3, no. 1 (August 20, 2018). doi:10.1007/s41062-018-0169-9.

Fahmi, Kwa Sally, Mohammed Fattah, and Alena Shestakova. “Behavior of Foundation Soil Improved by Stone Column under Cyclic Load.” Edited by A.D. Abramov and V. Murgul. MATEC Web of Conferences 239 (2018): 05015. doi:10.1051/matecconf/201823905015.

Shehata, H. F., T. M. Sorour, and A. L. Fayed. “Effect of Stone Column Installation on Soft Clay Behavior.” International Journal of Geotechnical Engineering (May 25, 2018): 1–13. doi:10.1080/19386362.2018.1478245.

Zukri, Azhani, and Ramli Nazir. “Sustainable Materials Used as Stone Column Filler: A Short Review.” IOP Conference Series: Materials Science and Engineering 342 (April 2018): 012001. doi:10.1088/1757-899x/342/1/012001.

Datye, K.R. “Settlement and bearing capacity of foundation system with stone columns.” Int. Symp. on Soil and Rock Improvement Techniques Including Geotextiles, Reinforced Earth, and Modern Piling Methods, Asian Institute of Technology (1982).

Sivakumar, V., Boyd, J.L, Black, J.A., and McNeil, J. A. “Effects of granular columns in compacted fills.” Proceedings of the Institution of Civil Engineers - Geotechnical Engineering 163, no. 4 (August 2010): 189–196. doi:10.1680/geng.2010.163.4.189.

Fatahi, B, H Khabbaz, and T Le. “Improvement of Rail Track Subgrade Using Stone Columns Combined with Geosynthetics.” Advances in Transportation Geotechnics 2 (September 13, 2012): 202–206. doi:10.1201/b12754-26.

Ashour, Samir. "The response of stone columns under the cyclic loading." PhD diss., University of Birmingham, 2016.

Fattah, Mohammed Y., Mohammed A. Al-Neami, and Ahmed Shamel Al-Suhaily. “Estimation of Bearing Capacity of Floating Group of Stone Columns.” Engineering Science and Technology, an International Journal 20, no. 3 (June 2017): 1166–1172. doi:10.1016/j.jestch.2017.03.005.

BS 1377. “Methods of Test for Soils for Civil Engineering Purposes” British Standards Institution (BSI) (1975). doi:10.3403/30306957.

ASTM. “Annual Book of American Society for Testing and Material Standards” ASTM Tech Publications (2003).

Shahu, J. T., and Y. R. Reddy. “Clayey Soil Reinforced with Stone Column Group: Model Tests and Analyses.” Journal of Geotechnical and Geoenvironmental Engineering 137, no. 12 (December 2011): 1265–1274. doi:10.1061/(asce)gt.1943-5606.0000552.

Wood, D. Muir, W. Hu, and D. F. T. Nash. “Group Effects in Stone Column Foundations: Model Tests.” Ground and Soil Improvement (January 2004): 119–128. doi:10.1680/gasi.31708.0016.

Al-Shaikly, A. ,2000 “Effect of stone grain size on the behavior of stone columns” M.Sc. Thesis, Building and Construction Engineering Department, University of Technology, Iraq.

Das, Braja M. “Advanced soil mechanics. Crc Press, 2013.

McKelvey, D., V. Sivakumar, A. Bell, and J. Graham. “Modelling Vibrated Stone Columns in Soft Clay.” Geotechnical Engineering 157, no. 3 (July 2004): 137–149. doi:10.1680/geng.

Abdual Husain, H. A. (2000), “The behavior of groups of stone columns in soft clay” M.Sc. Thesis, Building and Construction Engineering Department, University of Technology, Iraq.

Davisson, M. T. “High capacity piles. in Innovations in Foundation Construction.” Proceedings of a lecture series, Illinois Section ASCE, Chicago (1973).‏

Das, Braja M., and E. C. Shin. "Laboratory model tests for cyclic load-induced settlement of a strip foundation on a clayey soil." Geotechnical & Geological Engineering 14, no. 3 (1996): 213-225. doi: 10.1007/BF00452948.

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DOI: 10.28991/cej-2019-03091280


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