Abstract
A disconnected piled raft (DPR) foundation has been introduced as an effective pile design to reduce the vertical loading experienced by the pile. The characterization of DPRs has focused on the load transfer mechanism, foundation and soil settlement, bearing capacity, load distribution, and bending moment of the piles. DPR piles can act to increase the bearing capacity of the ground, and DPRs can reduce settlement while securing the bearing capacity. In this study, centrifuge model tests are performed to simulate the static behavior of DPRs under actual stress conditions. The behaviors of the DPR foundation for axial load, axial load distribution among the piles, and bending moment are compared to those of the connected piled raft foundation to understand the complex behaviors of DPRs. The centrifuge test results show that DPRs help reduce the pile axial load and bending moment during vertical loading. In addition, DPRs show smaller vertical settlement than shallow foundations. Therefore, we confirm that DPRs can be applied in foundation design as settlement reducers.
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Acknowledgements
This research was supported by an R&D project of Hyundai Engineering & Construction, and by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (Grant Number 2014R1A6A3A04056405). This study was supported by the Research Program funded by the SeoulTech (Seoul National University of Science and Technology).
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Park, HJ., Ko, KW., Song, YH. et al. Centrifuge modeling of disconnected piled raft using vertical pushover tests. Acta Geotech. 15, 2637–2648 (2020). https://doi.org/10.1007/s11440-020-00928-6
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DOI: https://doi.org/10.1007/s11440-020-00928-6