An Experimental study on static and dynamic behaviour of model pile foundations

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2015
Ünsever, Yeşim Sema
When the subsoil beneath a structure is weak to carry the loads from the superstructure, use of piled foundations is one of the widely employed alternatives. These types of foundations may also be subjected to transient or cyclic lateral loads arising from earthquake, wind, etc. Detailed case histories of dynamically loaded pile foundations are not too many in the literature. In this study, a series of static cyclic horizontal load tests and 1-g shaking table tests on various model foundations, such as piled raft, pile group, full raft, small raft, capped pile and single pile were performed in dry sand. In dynamic tests, the response of the pile foundations was investigated under cyclic loadings with variable frequencies. After testing stage, finite element software, PLAXIS 3D was used for few setups to have a deeper understanding of the behavior of the piled raft. The results showed that the raft has a significant effect on reducing the settlements and transmitting vertical load through the raft which causes stress increment in the soil. This stress increment causes to increase the amount of load carried by piles. Also, the behavior of the piled raft is affected considerably by the interaction of the piles and the raft, which leads to the conclusion that it is not plausible to assess the behavior of the piled raft by examining the components individually.

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Citation Formats
Y. S. Ünsever, “An Experimental study on static and dynamic behaviour of model pile foundations,” Ph.D. - Doctoral Program, Middle East Technical University, 2015.