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The Behavior of Enlarged Base Pile Under Compression and Uplift Loading in Partially Saturated Sand

Zaid H. Ghalib, Mahmood R. Mahmood

Abstract


The aim of this paper is to study the behavior of enlarged base piles embedded within partially saturated soils under compression and uplift loading. This type of pile is rarely excavated and cast on-site. Accordingly, to construct an enlarged base pile model, an excavator was designed and manufactured to give appropriate shape through drilling and casting in the laboratory through the design and manufacture of an excavator to produce piles with a shaft of 35 mm in diameter, 500 mm in length, and a base of 80 mm in diameter inclined at an angle of 60 degrees. Three different partial saturation soils were achieved by lowering the water level below the soil surface 20, 40, and 60 cm and measuring the suction force of each stage using a Tensiometer. The average matrix suction results were 6.4, 7.6, and 9.1 kPa for each lower water level, respectively. The test results showed that the bearing capacity of the enlarged base piles under compression load in partially saturated soil was higher than that in the case of full saturation because of matrix suction, with an improvement rate of 2.5–4.5 times compared with the case of fully saturated soil. Additionally, test results showed that the enlarged base piles subjected to uplift loading in partially saturated soil were significantly improved compared with the fully saturated condition, with an improvement rate of 1.5 - 3 times. The reason for this is the apparent surface cohesion of the sandy soil, which increases the bearing capacity of the sandy soil. This study sheds light on the phenomenon of apparent surface cohesion of sandy soil and the extent of its effect on increasing the soil’s resistance to the loads placed on it.

 

Doi: 10.28991/CEJ-2024-010-10-08

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Keywords


Enlarged Base Pile; Partially Saturated Soil; Matric Suction; Apparent Cohesion; SWCC; Uplift.

References


Hamza, A. S. H. A. (1994). Transmission line tower representation and its effect on the tower surge response calculation. Energy Conversion and Management, 35(12), 1087–1096. doi:10.1016/0196-8904(94)90012-4.

Dickin, E. A., & Leung, C. F. (1992). The influence of foundation geometry on the uplift behaviour of piles with enlarged bases. Canadian Geotechnical Journal, 29(3), 498–505. doi:10.1139/t92-054.

Kiriyama, T., Zhou, Y., & Asaka, Y. (2024). Estimation of belled pile uplift resistance in dense sand based on centrifugal experiments. Japanese Geotechnical Society Special Publication, 10(48), 1780–1785. doi:10.3208/jgssp.v10.os-37-01.

Al-Mosawe, M. J., Al-Shakarchi, Y. J., & Al-Taie, S. M. (2007). Embedded in Sandy Soils With Cavities. Journal of Engineering, 13(01), 1166–1186. doi:10.31026/j.eng.2007.01.03.

Jebur, M. M., Ahmed, M. D., & Karkush, M. O. (2020). Numerical Analysis of Under-Reamed Pile Subjected to Dynamic Loading in Sandy Soil. IOP Conference Series: Materials Science and Engineering, 671(1), 12084. doi:10.1088/1757-899X/671/1/012084.

Rashid Al-Qayssi, M., Faik Al-Wakel, S., & Khairalla Abdlazez Kando, A. (2018). Experimental Study of Model Piled Raft Foundation Embedded Within Partially Saturated Cohesionless Soils. Journal of Engineering and Sustainable Development, 2018(03), 62–75. doi:10.31272/jeasd.2018.3.6.

Mahmood, M. R., Al-Wakel, S. F. A., & Hani, A. A. (2017). Experimental and Numerical Analysis of Piled Raft Foundation Embedded within Partially Saturated Soil. Engineering and Technology Journal, 35(2A), 97–105. doi:10.30684/etj.35.2a.1.

Milovic, D. M., & Todorovic, T. (1985). Stresses and Displacements in an Anisotropic Soil Produced By a Ring Foundation. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 24(3), 821–827. doi:10.1016/0148-9062(87)90757-1.

Broms, B. B. (1963). Allowable Bearing Capacity of Initially Bent Piles. Journal of the Soil Mechanics and Foundations Division, 89(5), 73–90. doi:10.1061/jsfeaq.0000559.

Oloo, S. Y., Fredlund, D. G., & Gan, J. K. M. (1997). Bearing capacity of unpaved roads. Canadian Geotechnical Journal, 34(3), 398–407. doi:10.1139/t96-084.

Vanapalli, S. K., & Mohamed, F. M. O. (2007). Bearing Capacity of Model Footings in Unsaturated Soils. Experimental Unsaturated Soil Mechanics, 483–493. doi:10.1007/3-540-69873-6_48.

Oh, W. T., Vanapalli, S. K., & Puppala, A. J. (2009). Semi-empirical model for the prediction of modulus of elasticity for unsaturated soils. Canadian Geotechnical Journal, 46(8), 903–914. doi:10.1139/T09-030.

Taylan, Z. N., & Vanapalli, S. K. (2012). Estimation of the Shaft Capacity of Single Piles Using the Conventional and Modified β Method. Unsaturated Soils: Research and Applications, 255–262. doi:10.1007/978-3-642-31343-1_32.

ASTM D854-23. (2023). Standard Test Methods for Specific Gravity of Soil Solids by the Water Displacement Method. ASTM International, Pennsylvania, United States. doi:10.1520/D0854-23.

Ravindran, S., & Gratchev, I. (2022). Effect of Water Content on Apparent Cohesion of Soils from Landslide Sites. Geotechnics, 2(2), 385–394. doi:10.3390/geotechnics2020017.

ASTM D4253. (2019). Standard Test Methods for Maximum Index Density and Unit Weight of Soils Using a Vibratory Table. ASTM International, Pennsylvania, United States. doi:10.1520/D4253-16E01.

ASTM D4254-16. (2016). Standard Test Methods for Minimum Index Density and Unit Weight of Soils and Calculation of Relative Density. ASTM International, Pennsylvania, United States. doi:10.1520/D4254-16.

ASTM D3080-04. (2011). Standard Test Method for Direct Shear Test of Soils under Consolidated Drained Conditions ASTM International, Pennsylvania, United States. doi:10.1520/D3080-04.

Ridley, A. (2015). Soil suction — what it is and how to successfully measure it. Proceedings of the Ninth Symposium on Field Measurements in Geomechanics, 27–46. doi:10.36487/acg_rep/1508_0.2_ridley.

Li, X. (2008). Laboratory studies on the bearing capacity of unsaturated sands. PhD Thesis, University of Ottawa, Ottawa, Canada.

Vanapalli, S. K., Sun, R., & Li, X. (2011). Bearing capacity of an unsaturated sand from model footing tests. Unsaturated Soils - Proceedings of the 5th International Conference on Unsaturated Soils, 2, 1217–1222. doi:10.1201/b10526-189.

Fredlund, D. G., Sheng, D., & Zhao, J. (2011). Estimation of soil suction from the soil-water characteristic curve. Canadian Geotechnical Journal, 48(2), 186–198. doi:10.1139/T10-060.

Fredlund, D. G., & Xing, A. (1994). Equations for the soil-water characteristic curve. Canadian Geotechnical Journal, 31(4), 521–532. doi:10.1139/t94-061.

van Genuchten, M. T. (1980). A Closed‐form Equation for Predicting the Hydraulic Conductivity of Unsaturated Soils. Soil Science Society of America Journal, 44(5), 892–898. doi:10.2136/sssaj1980.03615995004400050002x.

Leong, E. C., & Rahardjo, H. (1997). Permeability Functions for Unsaturated Soils. Journal of Geotechnical and Geoenvironmental Engineering, 123(12), 1118–1126. doi:10.1061/(asce)1090-0241(1997)123:12(1118).

Terzaghi, K. (1943). Theoretical Soil Mechanics. John Wiley & Sons, Hoboken, United States. doi:10.1002/9780470172766.

Fattah, M. Y., Ahmed, M. D., & Mohammed, H. A. (2023). Behavior of Partially Saturated Cohesive Soil under Strip Footing. Journal of Engineering, 19(3), 298–311. doi:10.31026/j.eng.2013.03.02.

Abood, A. S., Fattah, M. Y., & Al-Adili, A. (2023). Assessment of shear strength characteristics of the unsaturated gypseous soil at various saturation degrees. Cogent Engineering, 10(2), 2283303. doi:10.1080/23311916.2023.2283303.

Fredlund, D. G., Rahardjo, H., & Fredlund, M. D. (2012). Unsaturated Soil Mechanics in Engineering Practice. John Wiley & Sons, Hoboken, United States. doi:10.1002/9781118280492.

Ibrahim, A. A., & Karkush, M. O. (2023). The Efficiency of Belled Piles in Multi-Layers Soils Subjected to Axial Compression and Pullout Loads: Review. Journal of Engineering, 29(09), 166–183. doi:10.31026/j.eng.2023.09.12.

Mahmood, M. R., Salim, N. M., & Al-Gezzy, A. A. (2021). Effect of Different Soil Saturation Conditions on the Ultimate Uplift Resistance of Helical Pile Model. E3S Web of Conferences, 318, 01012. doi:10.1051/e3sconf/202131801012.


Full Text: PDF

DOI: 10.28991/CEJ-2024-010-10-08

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