Experimental Study of a Square Foundation with Connected and Non-Connected Piled Raft Foundation Under Eccentrically Loaded

Document Type : Research Papers


1 Iran university of science and technology



In the recent years, non-connected piled raft foundation has been considered as an economical and practical deep foundation in the situation that high shear and concentrated loads may occur at the connection of the raft and pile head. This paper was presented an experimental study of a square foundation on the effects of parameters such as S/D, L/D and etc. in two cases of connected or non-connected piled raft system under the eccentrically loaded raft. The results was showed that square raft in the case of S/D = 3 and L/D = 8, the bearing capacity of the non-connected piles is more than that of the connected piles. The results of the experiments was showed pile length is more effective than the pile spacing in connected pile raft system. However by decreasing pile spacing, bearing capacity is increased in non-connected pile raft and pile spacing is more effective than the pile spacing in non-connected pile raft system. Comparison of bearing capacity and settlement indicated in the non-connected piled raft system, the longer piles not only has not much effect in increasing bearing capacity significantly, but also has lower effect on the reduction of the settlement. Also in non-connected piled raft system by increasing the pile spacing reduced BPI (bearing pile index) wile in connected piled raft system increased.


Main Subjects

Burland, J.B., Broms, B.B. and De Mello, V. F. (1977). “The behavior of foundations and structures”, Proceedings of the Ninth International Conference on Soil Mechanics and Foundation Engineering, Tokyo, Vol. II, 495-546.
Cao, X.D., Wong, I.H. and Chang, M.F. (2004). “Behavior of model rafts resting on pile-reinforced sand”, Journal of Geotechnical and Geoenvironmental Engineering, 130(2), 129-138.
El-Sawwaf, M. (2010). “Experimental study of eccentrically loaded raft with connected and unconnected short piles”, Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 136(10), 1394-1402.
Fioravante, V., Giretti, D., (2010). “Contact versus noncontact piled raft foundations", Canadian Geotechnical Journal, 47(11), 1271-1287.
Jamshidi Chenari, R., Ghorbani, A., Eslami, A. and Mirabbasi, F. (2018). "Behavior of piled raft foundation on heterogeneous clay deposits using random field theory", Civil Engineering Infrastructures Journal, 51(1), 35-54.
Kim, K.N., Lee, S.H., Kim, K.S., Chung, C.K., Kim, M.M. and Lee, H.S. (2001). “Optimal pile arrangement for minimizing differential settlements in piled raft foundations”, Computers and Geotechnics, 28, (4), 235-253.
Kumar, V. and Kumar, A. (2018). “An experimental study to analyse the behaviour of piled-raft foundation model under the application of vertical load”, Innovative Infrastructure Solutions, 3, 1-17.
Liang, F.Y., Chen, L.Z. and Shi, X.G. (2003). "Numerical analysis of composite piled raft with cushion subjected to vertical load", Computers and Geotechnics, 30, 443-453.
Luo, R., Yang, M. and Li, W. (2018). “Normalized settlement of piled raft in homogeneous clay”, Computers and Geotechnics, 103, 165-178.
Mahmood, M., Al-Wakel, S. and Abdulwahhab, I. (2018). “Three-dimensional analysis for piled raft machine foundation embedded in sand”, In: MATEC Web of Conferences, Vol. 162, pp. 01023, EDP Sciences.
Nakanishi, K. and Takewaki, I. (2013). "Optimum pile arrangement in piled raft foundation by using simplified settlement analysis and adaptive step-length algorithm", Geomechanics and Engineering, 5(6), 519.
Nemoto, H., Yaegashi, K., Takeuchi, Y., Nishimura, N., Matsmoto, T. and Kitiyodom, P. (2006). "Vertical load tests of model piled rafts with different pile head connection conditions", Proceedings of the Sixth International Conference on Physical Modelling in Geotechnics, Hong Kong, pp. 853-859.
Patil, S.A. Vasanwala and C.H. Solanki. (2016).”An experimental study of the eccentrically loaded piled raft”, International Journal of Geotechnical Engineering, 10(1), 40-45.
Prakoso, W.A. and Kulhawy, F.H. (2001). “Contribution to piled raft foundation design”, Journal of Geotechnical and Geoenvironmental Engineering, 127(1), 17-24.
Rabiebi, M. (2009). "Parametric study for piled raft foundations", Electronic Journal of Geotechnical Engineering, 14, 1-11.
Rajib, S., Dutta, S.C. and Haldar, S. (2015) "Effect of the raft and pile stiffness on seismic response of soil-piled raft- structure system", Structural Engineering and Mechanics, 55(1), 161-189.
Rasouli, H., Saeedi Azizkandi, A., Baziar, M., Modarresi, M. and Shahnazari, H. (2015). “Centrifuge modeling of non-connected piled raft system.” International Journal of Civil Engineering, 13(2), 114-123.
Reul, O. and Randolph, M.F. )2004(. “Design strategies for piled rafts subjected to non-uniform vertical loading”, Journal of Geotechnical and Geoenvironmental Engineering, 130(1), 1-13.
Saeedi Azizkandi, A., Baziar, M.H. and Fallah, A. (2017(. “3D dynamic Finite Element analyses and 1 g shaking table tests on seismic performance of connected and no-connected piled raft foundations”, KSCE Journal of Civil Engineering, 22(5), 1750-1762.
Saeedi Azizkandi, A. and Fakher, A. (2014). "A simple algorithm for analyzing a piled raft by considering stress distribution", Civil Engineering Infrastructures Journal, 47(2), 215-227.
Sharma, V.J., Vasanvala, S.A. and Solanki, C.H. (2011).  "Effect of cushion on composite piled-raft foundation", Journal of Engineering Research and Studies, 2(4), 132-135.
Sinha, A. and Hanna, A.M. (2016). “3D numerical model for piled raft foundation”, International Journal of Geomechanics, 17(2), 04016055.
Taghavi Ghalesari, A. and Janalizadeh Choobbasti, A. (2018). “Numerical analysis of settlement and bearing behaviour of piled raft in Babol clay”, European Journal of Environmental and Civil Engineering, 22(8), 978-1003.
Volume 52, Issue 1
June 2019
Pages 185-203
  • Receive Date: 02 July 2018
  • Revise Date: 12 January 2019
  • Accept Date: 13 February 2019
  • First Publish Date: 01 June 2019