The Effect of Stone Column (Nailing and Geogrid) on Stability of Expansive Clay

By enhancing the applicatıon of grounds for establishment and due to the lack of appropriate sites, engineers attempt to seek out a new method to reduce the weakness of soils. İn aspect of economic situation, various ways have been used to decrease the weak grounds. Because of the rapid development of infrastructural facilities, spreading the construction operation is an obligation. Furthermore, in various sites with the really bad soil situation, engineers have considered obvious problems. One of the most essential ways for developing the weak soils is stone column. Obviously, the method was introduced in France in 1830 to improve a native soil initially. Stone columns have an expanding range of usage in different rough foundation sites all over the world to increase the bearing capacity, to reduce the whole and differential settlements, to enhance the rate of consolidation, to stabilize slopes stability of embankments and to increase the liquefaction resistance as well. A recent procedure called installing vertical nails along the round stone columns in order to make better the performance of considered columns is offered. Moreover, thanks to the enhancing the nail diameter, number and embedment nail depth, the positive points of vertical circumferential nails increases. Based on the result of this study, load caring capacity will be develop with enhancing the length and the power of reinforcements in vertical encasement stone column (CESC). In this study, the main purpose is comparing two methods of stone columns (installed a nail surrounding the stone columns and using geogrid on clay) for enhancing the bearing capacity, decreasing the whole and various settlements.

Authors:

• Komeil Valipourian
• Mohsen Ramezan Shirazi
• Orod Zarrin Kafsh

Keywords:

• Bearing Capacity
• Clay
• Geogrid
• Nailing
• Settlements
• Stone Column.

References:

[1] Ling I, Leshchinsky D, Tatsuoka F. (2003) "Reinforced soil engineering:
advances in research and practice", Marcel Dekker Inc.
[2] Hejazi, S. M. et al. (2012) "A simple review of soil reinforcement by
using natural and synthetic fibers. Construction and Building Materials",
30, 100–116.
[3] Boushehrian, et al. (2011) "Modeling of the cyclic behavior of shallow
foundations resting on geomesh and grid-anchor reinforced sand",
Geotextiles and Geomembranes, 29(3), 242–248.
doi:10.1016/j.geotexmem.2010.11.008.
[4] Han, J., S. K. Pokharel, X. Yang, C. Manandhar, D. Leshchinsky, I.
Halahmi, and R.L. Parsons. (2011) “Performance of geocell-reinforced
RAP bases over weak subgrade under full scale moving heel loads”,
ASCE Journal of Materials in Civil Engineering, 23, no.11:1525-1535.
[5] Sharma, R. S., Kumar, P., Nagendra, G. 2004. Compressive load
response of granular piles reinforced with geogrids. Can. Geotech. J. 41:
187–192. [6] Gneil, J., Bouazza, A. 2009. Improvement of soft soils using geogrid
encased stone columns. Geotextiles and Geomembranes 27: 167–175.
[7] Deb, K., Samadhiya, N. K., Namdeo, J. B. 2010. Laboratory model
studies on unreinforced and geogrid-reinforced sand bed over stone
column-improved soft clay. Geotextiles and Geomembranes: 1- 7.
[8] Malarvizhi, S. N., Ilamparuthi, K. 2004. Load versus settlement of
claybed stabilized with stone and reinforced stone column. 3rd Asian
Reg. Conf. on Geosynt.: 322-329.
[9] Lee, DY, Kim, SB, Song, AR and Yoo, CS (2006). “Load Carrying
Capacity and Failure Mechanism of Geogrid Reinforced Stone Columns:
Reduced-Scale Model Tests”, Journal of KGS, Vol. 22, No.10, pp 121-
129.
[10] McKelvey D, Sivakumar V, Bell A, Graham J (2004) Modeling vibrated
stone columns in soft clay. Proc Inst Civil Eng Geotech Eng 157(Issue
GE3):137–149.
[11] R. Shivashankar, M. R. Dheerendra Babu, Sitaram Nayak, R. Manjunath
2010 Stone Columns with Vertical Circumferential Nails: Laboratory
Model Study.
[12] B. Sitaram Nayak Ramaiah Shivashankar, Madhalam Ramanaidu
Dheerendra Babu (2011) Performance of stone columns with
circumferential nails.