Evaluation of Piled Raft Performance Using a Verified 3D Nonlinear Numerical Model

被引：20
作者：
Alnuaim A.M. [1 ]
El Naggar H. [2 ]
El Naggar M.H. [3 ]
机构：
[1] Department of Civil Engineering, College of Engineering, King Saud University, Riyadh, P.O. Box 800, Riyadh
[2] Department of Civil and Resource Engineering, Dalhousie University, 1360 Barrington Street, Halifax, B3H 4R2, NS
[3] Department of Civil and Environmental Engineering, University of Western Ontario, 1151 Richmond Street, London, N6A 5B9, ON
来源：
Geotechnical and Geological Engineering | 2017年 / 35卷 / 04期
关键词：
Contact pressure; FEA; Load sharing; Piled raft; Sand;
D O I：
10.1007/s10706-017-0212-1
中图分类号：
学科分类号：
摘要：
The piled raft foundation system presents a feasible foundation option for high rise buildings. Piled raft foundations have a complex three-dimensional soil-structure interaction scheme including the pile-soil interaction, pile–pile interaction, raft-soil interaction, and finally the piles-raft interaction. Consequently, comprehensive 3D numerical models are sought to investigate this complex interaction. In this paper, a 3D finite element model was verified using published geotechnical centrifuge test results to further enhance the accuracy of the model. The study considered piled rafts installed in sand with stiffness that varies linearly with depth. A comprehensive parametric study was conducted to evaluate the effect of different foundation parameters including: pile diameter, pile spacing, raft width, and raft thickness on the overall behavior of the piled raft. The load carrying capacity of the piled raft and the load sharing mechanism between the raft and piles are evaluated. It was found that the load carried by piles is higher for rigid rafts (Kf > 600) due to the minimal interaction between the raft and subsoil compared to the relatively flexible rafts (Kf < 150). Moreover, the load transmitted by the raft increased by about 75% as the raft width increased from 4 to 7 m. © 2017, Springer International Publishing Switzerland.
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页码：1831 / 1845
页数：14
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