A comparison of two dimensional and three dimensional finite element analysis for settlement behavior of piled raft foundations

Kaltakcı, Volkan
In this study, the settlement behavior of the piled raft foundations resting on overconsolidated clays under uniform loading, is investigated for different pile configurations and load levels. A total of 100 plane strain and three dimensional finite element analyses are carried out and the results of these analyses are compared both with each other and with the results presented by Reul & Randolph (2004). The material parameters used in the analysis are selected mainly referring to the previous studies cited above on the same subject and slight modifications are made for convenience in the analysis. The analysis method and the applied pile configurations and load levels are directly taken from the reference study, excluding the soil model employed. A drained Mohr Coulomb failure criteria is employed in the analysis of this study in modeling the soil instead of an elastoplastic model which was used in the analysis of the reference study. The results are evaluated for the average and differential settlements of the foundations and it is seen that; although the average and differential settlements calculated in this study are not always very close to the values calculated in the reference study, the calculated settlement reduction factors due to piles (especially for the average settlements) compared well with the findings of the reference study for all pile configurations and load levels considered. Based on this, a new approach is suggested to estimate the average settlements of the piled raft foundations. Moreover, correction factors are recommended in order to estimate the average settlements of the piled rafts by directly using the programs employed throughout the thesis.


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Citation Formats
V. Kaltakcı, “A comparison of two dimensional and three dimensional finite element analysis for settlement behavior of piled raft foundations,” M.S. - Master of Science, Middle East Technical University, 2009.