Ali, Zahid (2026) Thresholds for Pile Cap Rigidity for Multi-Pile Foundations. Masters thesis, Concordia University.
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Abstract
For decades, engineers have used traditional methods to design pile-cap foundations, which is based on piles will carry equal load. The cap thickness was determined based on span/thickness ratio to be rigid; this approach has been deemed inadequate. For less rigid caps or rather flexible caps, piles located at the edges carry less while those situated at the center of the cap carry much more, which overlook the concept of the geotechnical design of pile foundations. Whereas overly thick caps may impose unnecessary load and resources.
This thesis presents a three-dimensional numerical model, to simulate the cap/piles system in a group. The model is capable of capturing the cap thickness for a uniform load acting on piles within the group. The model utilizes the finite element technique and the commercial software ABAQUS. It examines the interactions among piles, and piles spacing, diameter, and length, to determine the cap rigidity for a given pile group's geometry.
The results are presented as design charts that determine the cap thickness thresholds for a given pile/cap/soil configuration. The practical design chart translates these findings into a direct engineering application; can determine the cap thickness for a given group configuration.
| Divisions: | Concordia University > Gina Cody School of Engineering and Computer Science > Building, Civil and Environmental Engineering |
|---|---|
| Item Type: | Thesis (Masters) |
| Authors: | Ali, Zahid |
| Institution: | Concordia University |
| Degree Name: | M.A. Sc. |
| Program: | Civil Engineering |
| Date: | 6 January 2026 |
| Thesis Supervisor(s): | Hanna, Adel |
| Keywords: | Pile cap rigidity, numerical modeling, soil-pile interaction, load ratio, load uniformity |
| ID Code: | 996731 |
| Deposited By: | Zahid Ali |
| Deposited On: | 29 Jun 2026 14:33 |
| Last Modified: | 29 Jun 2026 14:33 |
References:
1. Alnuiam, A., El Naggar, H., & El Naggar, M. H. (2013, September). Performance of piled-raft system under axial load. In 18th International Conference on Soil Mechanics and Geotechnical Engineering (pp. 2663-2666).2. Basha, A., Elmorsy, S., Mansour, W., & Ramadan, B. (2024). Effect of the pile cap length and the soil relative density on the pile cap – pile – dense soil interaction: Experimental investigation. Case Studies in Construction Materials, 20, e03169. https://doi.org/10.1016/j.cscm.2024.e03169
3. Bessimbayev, Ye., Niyetbay, S., Zhambakina, Z., & Enayat, T. (2025). Exploring the Influence of Pile Cap Thickness on the Effectiveness of Pile Cap Foundations through Numerical Analysis. Architecture and Civil Engineering, 2(1), 22–27. https://doi.org/10.51301/ACE.2025.I1.04
4. Canadian Standards Association. (2019). Design of concrete structures (CSA standard A23.3:19). Retrieved from https://subscriptions.techstreet.com/products/836680
5. Clancy, P., Randolph, M.F.: Simple design tools for piled raft foundations. Geotechnique 46(2), 313–328 (1996)
6. Fattah, M. Y., Al-Mosawi, M. J., & Al-Zayadi, A. A. O. (2014). Contribution to long term performance of piled raft foundation in clayey soil. International journal of civil engineering and technology (IJCIET), 5(7), 130-148.
7. Geotechdata.info. (2013). Soil elastic Young's modulus. [Online] Available at: http://geotechdata.info/parameter/soil-elastic-young-modulus.html [Accessed 02 December 2018]
8. González, F., Carbonari, S., Padrón, L. A., Morici, M., Aznárez, J. J., Dezi, F., Maeso, O., & Leoni, G. (2020). Benefits of inclined pile foundations in earthquake resistant design of bridges. Engineering Structures, 203, 109873. https://doi.org/10.1016/J.ENGSTRUCT.2019.109873
9. Halder, P., & Manna, B. (2022). Performance evaluation of piled rafts in sand based on load-sharing mechanism using finite element model. International Journal of Geotechnical Engineering, 16(5), 574–591. https://doi.org/10.1080/19386362.2020.1729297
10. Hammouli, S. E., Hanna, A., Lin, L., & Khalifa, M. (2020). Performance of Pile Cap Foundation with Respect to Cap Thickness. Proceedings of the International Conference on Civil, Structural and Transportation Engineering. https://doi.org/10.11159/iccste20.205
11. Hammouli, S. E., Hanna, A., Lin, L., & Khalifa, M. (2021). Role of cap thickness in Pile-Cap Foundation. International Journal of Civil Infrastructure. https://doi.org/10.11159/ijci.2021.013
12. He, C. L., & Gong, C. Z. (2014). Influence of Pile Cap Thickness on the Bearing Characteristics of Group Piles Foundation. Applied Mechanics and Materials, 638–640, 471–474. https://doi.org/10.4028/WWW.SCIENTIFIC.NET/AMM.638-640.471
13. He, D., Cheng, Y., Liu, H., & Lin, H. (2025). Pile–Soil Interaction and Group Pile Effect in Composite Foundation Under Different Pile Length Conditions. Buildings 2025, Vol. 15, Page 1248, 15(8), 1248. https://doi.org/10.3390/BUILDINGS15081248
14. Horikoshi K, Matsumoto T, Hashizume Y, Watanabe T, Fukuyama H (2003), "Performance of piled raft foundations subjected to static horizontal loads". International Journal of Physical Modelling in Geotechnics, Vol. 3 No. 2 pp. 37–50, doi: https://doi.org/10.1680/ijpmg.2003.030204
15. Jawad, F. W., Al-Taie, E. T., & Fattah, M. Y. (2020). Static interaction in soil–pile-cap system using three-dimensional analysis. Periodicals of Engineering and Natural Sciences, 8(2), 1049-1059
16. Juneja, A., Joseph, A., & Murty, D.S. (Eds.). (2025). GeoVadis: The Future of Geotechnical Engineering (Volume 1) (1st ed.). CRC Press. https://doi.org/10.1201/9781003645917
17. Lin, L., Sinha, A., Hanna, A. (2019). Influence of Cap Rigidity on the Performance of Piled-Cap Foundation. In: El-Naggar, H., Abdel-Rahman, K., Fellenius, B., Shehata, H. (eds) Sustainability Issues for the Deep Foundations. GeoMEast 2018. Sustainable Civil Infrastructures. Springer, Cham. https://doi.org/10.1007/978-3-030-01902-0_10
18. Liu, J., He, J., & Ding, B. Y. (2006). 3D Finite Element Analysis on Bearing Capacity Characteristics of the Composite Ground. Ground Modification and Seismic Mitigation, 305–312. https://doi.org/10.1061/40864(196)41
19. Liu, Ming-Quan, Huang, Da, Song, Yi-Xiang, Cen, Duo-Feng, Numerical and Theoretical Study on the Settlement of Capped Piles Composite Foundation under Embankment, Advances in Civil Engineering, 2020, 3978780, 11 pages, 2020. https://doi.org/10.1155/2020/3978780
20. Lodha, M., Arora, R.P., Solanki, A. (2021). Finite Element Analysis of Piled Raft Foundation in Clay and Sand. In: Patel, S., Solanki, C.H., Reddy, K.R., Shukla, S.K. (eds) Proceedings of the Indian Geotechnical Conference 2019. Lecture Notes in Civil Engineering, vol 137. Springer, Singapore. https://doi.org/10.1007/978-981-33-6466-0_48
21. Meyerhof, G. G. (1976). Bearing capacity and settlement of pile foundations. Journal of the Geotechnical Engineering Division, 102(3), 197–228. https://doi.org/10.1061/ajgeb6.0000243
22. Modak, R., Bhowmik, D., Singh, B. (2022). 3D Numerical Study of the Behavior of Piled Raft Foundation on Soft Clay with Uniform and Varying Pile Lengths. In: Satyanarayana Reddy, C.N.V., Muthukkumaran, K., Satyam, N., Vaidya, R. (eds) Ground Characterization and Foundations. Lecture Notes in Civil Engineering, vol 167. Springer, Singapore. https://doi.org/10.1007/978-981-16-3383-6_49
23. Mohamad, Z., Fardoun, F., & Meftah, F. (2021). A review on energy piles design, evaluation, and optimization. Journal of Cleaner Production, 292, 125802. https://doi.org/10.1016/J.JCLEPRO.2021.125802
24. M. Nazari and J. P. Webb, "A Structured Grid Finite-Element Method Using Computed Basis Functions," in IEEE Transactions on Antennas and Propagation, vol. 65, no. 3, pp. 1215-1223, March 2017. https://doi.org/10.1109/TAP.2017.2653764
25. Poulos, H.G.: Piled raft and compensated piled raft foundations for soft soil sites. Adv. Des. Test. Deep Found. 129, 214–234 (2005)
26. Rajeswari, J. S., & Sarkar, R. (2024). Adequacy of batter piles under seismic conditions: A review of past performances and investigations. Structures, 61, 106022. https://doi.org/10.1016/J.ISTRUC.2024.106022
27. Randolph, M.F.: Design of piled raft foundations. In: Proceedings of International Symposium on Recent Developments in Laboratory and Field Tests and Analysis of Geotechnical Problems, Bangkok, pp. 525–537 (1983)
28. Randolph, M. F., & Wroth, C. P. (1978). Analysis of deformation of vertically loaded piles. Journal of the Geotechnical Engineering Division, 104(12), 1465–1488. https://doi.org/10.1061/ajgeb6.0000729
29. Ren, Y., Chen, Z., & Zhu, W. (2025). A Numerical Study of the Lateral Load-Sharing Mechanism of the Pile Cap in a 3 × 3 Pile Group. Buildings 2025, Vol. 15, Page 1431, 15(9), 1431. https://doi.org/10.3390/BUILDINGS15091431
30. Sharma, M. (2019). Effect of Pile Layout and Pile Cap Thickness on Load Distribution in Piles. In: Rao, A., Ramanjaneyulu, K. (eds) Recent Advances in Structural Engineering, Volume 1. Lecture Notes in Civil Engineering, vol 11. Springer, Singapore. https://doi.org/10.1007/978-981-13-0362-3_3
31. Sinha, A., & Hanna, A. M. (2016b). 3D Numerical model for Piled Raft Foundation. International Journal of Geomechanics, 17(2). https://doi.org/10.1061/(asce)gm.1943-5622.0000674
32. Tang, L., Cui, Y., Chen, J., Yang, G., Sun, S., Li, G., Sun, Q., & Jia, H. (2023). Analysis and research on the difference of design codes for vertical bearing capacity of pile foundation in cold regions. In Cold Regions Science and Technology (Vol. 206). Elsevier B.V. https://doi.org/10.1016/j.coldregions.2022.103723
33. Viggiani, C., Mandolini, A., & Russo, G. (2011). Soil–structure interaction and the design of pile cap. Piles and Pile Foundations, 128–150. https://doi.org/10.1201/B17768-10/PILE-TESTING-CARLO-VIGGIANI-GIANPIERO-RUSSO-ALESSANDRO-MANDOLINI
34. Wang, T., Wang, H., Meng, K., Liang, Z., & Xing, G. (2018). Three-dimensional Numerical Analysis of Stress and Deformation of Soft Soil-pile group-pile Cap System under Coal Pile Load. DEStech Transactions on Computer Science and Engineering. https://doi.org/10.12783/DTCSE/ICMSA2018/23234
35. Wang, T., Qu, S., Huang, K., Liu, K., Connolly, D. P., & Luo, Q. (2025). Performance comparison of capped pile and piled beam support systems for embankments on soft soils. Transportation Geotechnics, 55, 101703. https://doi.org/10.1016/J.TRGEO.2025.101703
36. Wu, H., Gao, S., Wang, R. et al. Generation of multi-axis swept mesh in a global way. Engineering with Computers 35, 1121–1139 (2019). https://doi.org/10.1007/s00366-018-0654-y
37. Xue, J., Song, N., Yang, Y., & Ge, X. (2013). Finite Element Analysis of the Pile-Cap of Laterally Loaded Variable Rigidity Pile (Pile Partner). Applied Mechanics and Materials, 256–259(PART 1), 450–453. https://doi.org/10.4028/WWW.SCIENTIFIC.NET/AMM.256-259.450
38. Zhang, P., Chouw, N., Wang, Z., & Duanmu, X. (2025). Behaviour of pile caps with socket connections and different embedment depths under vertical loads. Engineering Structures, 346, 121694. https://doi.org/10.1016/J.ENGSTRUCT.2025.121694
39. Zhang, Y. Y., Xu, L. H., & Chi, Y. (2008). The Numerical Study on Load-Transferring Model for SFRC Double-Column Combined Six-Pile Caps. Key Engineering Materials, 400–402, 321–327. https://doi.org/10.4028/www.scientific.net/kem.400-402.321
40. Zienkiewicz, O. C., Taylor, R. L., & Zhu, J. Z. (2005). The Finite Element Method: Its Basis and Fundamentals. Elsevier.
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