Abstract
Piled-cap foundations are recognized for sharing the total load by the piles and the cap. In practice, it is assumed that the cap will distribute uniformly the load to the piles, which is often used in choosing the thickness of the cap. In the literature, research in this field remained lagging behind due to the difficulties associated in modeling. This is due to the fact that the load sharing mechanism of piled-cap foundation is a complex soil-structure problem governed by pile/cap geometry, soil condition, etc. It is of interest to note that a flexible cap will lead to uneven load distribution among the piles, which offsets the principle of design of pile foundation. It may, in turn, lead to failure of some piles in the group or even a catastrophic failure of the foundation. While, a non-flexible (i.e., rigid) cap may lead to uniform load distribution among the piles in the group, which will minimize or eliminate differential settlements within the cap. However, a thick cap will impose additional load due to its own weight and accordingly, it may in increase the total settlement of the foundation.
This paper presents the results from a three-dimension finite element model to examine the role of the cap geometry on the load sharing mechanism of the piled-cap foundation. The effect of the cap rigidity in terms of its size, thickness and pile spacing were examined. The modified Drucker-Prager cap plasticity model provides an excellent basis for analyzing the stress-strain of soil continuum constitutive law, and the software “ABAQUS”, which is based on pure solid mechanics principles has been used successfully to simulate the problem stated.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Adebar, P., Kuchma, D., Collins, M.P.: Strut-and-tie models for the design of pile caps: experimental study. ACI Struct. J. 87(1), 81–92 (1990)
Ai, Z.Y., Han, J., Yan, Y.: Elastic analysis of single pile-rigid circular raft system in layered soils. Adv. Deep Found. 132, 1–14 (2005)
Clancy, P., Randolph, M.F.: Simple design tools for piled raft foundations. Geotechnique 46(2), 313–328 (1996)
Griffiths, D.V., Clancy, P., Randolph, M.F.: Piled raft foundation analysis by finite elements. In: Proceedings of the 7th International Conference on Computational Methods and Advances in Geomechanics, Carins, vol. 2, pp. 1153–1157 (1991)
Jiu, Y., Huang, M.: A simplified nonlinear method for pie group analysis considering pile cap flexibility. New Front. Geotech. Eng. 243, 38–46 (2014)
Hibbit, H.D., Karlsson B.L, Sorrensen: ABAQUS Theory Manual and all Manuals, Guide, Online support (2007)
Katzenbach, R., Arslan, U., Moormann, C.: Piled Raft Foundation Projects in Germany. Design Applications of Raft Foundations. Thomas Telford, London (2000)
Katzenbach, R., Reul, O.: Design and performance of piled rafts. In: Proceedings of XIV ICSMFE, Hamburg, vol. 4, pp. 2253–2256 (1997)
Kim, K.N., Lee, S.H., Kim, S.K., Chung, C.K., Kim, M.M., Lee, H.S.: Optimal pile arrangement for minimizing differential settlements in piled raft foundations. Comput. Geotech. 28, 235–253 (2001)
Poulos, H.G.: Piled raft and compensated piled raft foundations for soft soil sites. Adv. Des. Test. Deep Found. 129, 214–234 (2005)
Poulos, H.G.: Methods of analysis of piled raft foundations, TC18 Report. International Society of Soil Mechanics and Geotechnical Engineering (2001)
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)
Sabnis, G.M., Gogate, A.B.: Investigation of thick slab (pile cap behavior). J. ACI 8(1), 35–39 (1984)
Sinha, A., Hanna, A.: 3-D numerical model for piled-raft foundation. Int. J. Geomech. (2016). https://doi.org/10.1061/(ASCE)GM.1943-5622.0000674
Small, J.C., Zhang, H.H.: Behaviour of piled raft foundations under lateral and vertical loading. Int. J. Geomech. 2(1), 29–45 (2002). https://doi.org/10.1061/(ASCE)1532-3641
Yamashita, K., Yamada, T., Hamada, J.: Investigation of settlement and load sharing on piled rafts by monitoring full-scale structures. Soils Found. 51(3), 513–532 (2011)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2019 Springer Nature Switzerland AG
About this paper
Cite this paper
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
Download citation
DOI: https://doi.org/10.1007/978-3-030-01902-0_10
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-01901-3
Online ISBN: 978-3-030-01902-0
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)