Journal of Structural and Construction Engineering

Journal of Structural and Construction Engineering

Parametric Study on the Differential Settlement of Piled Raft Foundations

Document Type : Original Article

Authors
sanaz shahbazi 1
Fariba Behrouz Sarand 2
Naseraldin shahbazi 3
Vahid Akrami 4
1 M.Sc. graduate, Civil Engineering department, Islamic Azad university Tabriz Branch, ,Tabriz,, Iran
2 Assistant Professor, Civil Engineering department, Islamic Azad university Tabriz Branch, Tabriz, Iran
3 Assistant Professor, Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran
4 Associate Professor, Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran
10.22065/jsce.2025.470873.3554
Abstract
Differential settlement in pile foundations can adversely affect pile heads, foundations, and the structures resting on them. This article investigates the influence of various parameters such as pile length, diameter, spacing, and cap thickness on the differential settlement of wide pile foundations through finite element analysis. For this purpose, a raft foundation was modeled with varying numbers of piles and subjected to a distributed load using Abaqus software. The results showed that using a single pile at the center of the cap reduces settlement by 36%, and increasing the number of piles to 16 can reduce the foundation settlement by 68% compared to the raft foundation without piles. Furthermore, results showed that increasing the pile diameter from 60 to 100 centimeters has little impact on the amount of settlement, but it reduces the stresses developed in the body of the pile. Additionally, increasing pile length from 12 to 18 meters reduced immediate settlement at the center of the foundation by 33%. However, constant settlement at the edges caused a slight increase in differential settlement. Finally, it was observed that increasing the thickness of the cap is an effective solution for reducing differential settlement in pile foundations. With the increase in cap thickness, the load distribution becomes more uniform across the piles, leading to a reduction in differential settlement and an overall improvement in foundation performance. Investigations showed that the amount of uneven settlement in the foundation has a direct relationship with the ratio of the free distance between the last row of piles and the edge of the cap to the thickness of the cap, such that for samples with a ratio of less than 2.5, the uneven settlement is almost negligible. These findings can also result in a more efficient parameter selection process, and prevention of uneven differential settlement.
Keywords
Raft pile foundation
Pile group
Differential settlement
Finite element analysis
ABAQUS software

Subjects

[1] Horikoshi, K., and Randolph, M.F. (1998). A contribution to optimum design of piled rafts. Geotechnique, 48(3), 301-317.
 
[2] Prakoso, W.A., and Kulhawy, F. H. (2001). Contribution to piled raft foundation design. Journal of geotechnical and geoenvironmental engineering, 127(1), 17-24.
 
[3] McCabe, B.A., and Lehane, B.M. (2006). Behavior of axially loaded pile groups driven in clayey silt. Journal of Geotechnical and Geoenvironmental Engineering, 132(3), 401-410.
 
[4] McCabe, B.A., and Sheil, B.B. (2015). Pile group settlement estimation: suitability of nonlinear interaction factors. International Journal of Geomechanics, 15(3), 04014056.
 
[5] Zhan, Y. G., Wang, H., & Liu, F. C. (2012). Modeling vertical bearing capacity of pile foundation by using ABAQUS. Electronic Journal of Geotechnical Engineering, 17(M), 1855-1865.
 
[6] Sinha, A., and Hanna, A.M. (2017). 3D numerical model for piled raft foundation. International Journal of Geomechanics, 17(2), 04016055.
 
[7] Mali, S., and Singh, B. (2018). Behavior of large piled-raft foundation on clay soil. Ocean Engineering, 149, 205-216.
 
[8] Hejazirad, S., Ghareh, S., Eslami, A., & Ganjian, N. (2021). Comparison of behavior of Drilled Displacement piles in laboratory and field (Case study; Anzali sand). Journal of Structural and Construction Engineering, 8(8), 49-68. doi: 10.22065/jsce.2021.255307.2281
 
[9] Malekkhani, M. J., & Bolouri Bazzaz, J. (2021). An investigation on the bearing capacity of piled raft foundations experimentally and comparison with modified hyperbolic model results. Journal of Structural and Construction Engineering, 8(1), 307-326. doi: 10.22065/jsce.2019.171280.1779
 
[10] Shooshpasha, I., and Sharafkhah, M. (2021). Experimenta Lstudy of Behavior of Piled Raft Foundations under Vertical Loading in Sand. Journal of Civil and Environmental Engineering, 51.3(104), 87-101. doi: 10.22034/jcee.2019.9256
 
[11] Nooralizadeh, O., Rahimi, S., Hoseinzadeh, M., & Ebadi Jamkhaneh, M. (2022). Investigation of steel moment-resisting frame relies on deep foundation under normal fault rupture. Journal of Structural and Construction Engineering, 9(2), 152-171. doi: 10.22065/jsce.2021.292098.2477
 
[12] Asadinia, A., Amirafshari, S., & Ghanbari, A. (2022). New equation to determine the load percentage carried by raft in piled raft foundations. Amirkabir Journal of Civil Engineering, 54(8), 3139-3154. doi: 10.22060/ceej.2022.20051.7329
 
[13] Susila, E., Syahputra, M. Y., Sahadewa, A., & Eka Putri, K. M. (2019). An Evaluation of Pile-Raft Interaction in Cohesive Soils using 3D Finite Element Method. Journal of Engineering & Technological Sciences, 51(5). doi: 10.5614/j.eng.technol.sci.2019.51.5.5
 
[14] Bhartiya, P., Chakraborty, T., & Basu, D. (2022). Load-settlement response of piled raft foundations in sand. Geomechanics and Geoengineering, 17(4), 1260-1283. doi: 10.1080/17486025.2021.1928767
 
[15] Jameel, M. M., & Ahmed, B. A. (2021). Response of Piles Group embedded in Sandy Soil with Cavities to Seismic Loading. In IOP Conference Series: Earth and Environmental Science (Vol. 856, No. 1, p. 012017). IOP Publishing. doi: 10.1088/1755-1315/856/1/012017
 
[16] Modak, R., & Singh, B. (2022). A parametric study of large piled raft foundations on clay soil. Ocean Engineering, 262, 112251. doi: 10.1016/j.oceaneng.2022.112251
 
[17] Fattah, M. Y., Salim, N. M., & Khalifa, K. R. (2023). Parametric study of unconnected piled rafts in clayey soil using finite element method. Innovative Infrastructure Solutions, 8(1), 16. doi: 10.1007/s41062-022-00987-6
 
[18] Jassim, A., Ganjian, N., & Eslami, A. (2023). Investigation of Load-Displacement Behavior of Helical Pile in Wet and Saturated Sand with FCV Apparatus. Journal of Structural and Construction Engineering, 10(5), 25-42. doi: 10.22065/jsce.2022.350470.2869
 
[19] Mohammad-Alinejad, R., Bayat, M., Nadi, B., & Pakbaz, M. S. (2023). Effect of degree of freedom of movement on the bearing capacity and efficiency coefficient of pile group adjacent to sandy slope. Journal of Structural and Construction Engineering, 10(1), 95-113. doi: 10.22065/jsce.2022.321897.2678
 
[20] Alsanabani, N., T. AL-Refeai, and A. Alshenawy, Simplified Method for Designing Piled Raft Foundation in Sandy Soils. Geotechnical Engineering, 2017. 48(4): p. 122-128.
 
[21] Hibbitt, Karlsson, & Sorensen. (2016). Abaqus/CAE User's Manual. Hibbitt, Karlsson & Sorensen, Incorporated.
 
[22] Su, K., & Li, Y. (2009). Discussion of extended drucker-prager yield criterion in slope stability analysis. In 2009 Asia-Pacific Power and Energy Engineering Conference (pp. 1-4). IEEE. doi: 10.1109/APPEEC.2009.4918285
Journal of Structural and Construction Engineering
Volume 12, Issue 09 - Serial Number 98
December 2025
Pages 148-171

  • Receive Date 20 November 2024
  • Revise Date 18 January 2025
  • Accept Date 07 February 2025