Group Effect of Dragload in Pile Groups Embedded in Consolidating Soil under Embankment Load

다국어 초록 (Multilingual Abstract)

In this paper, model tests and numerical simulations on 3 × 3 pile group embedded in consolidating soil under embankment load with different pile spacings are carried out. Single pile and 2 × 2 pile group are studied for comparative analyses. The performances of dragload versus relative displacement of pile-soil, load sequence and load rate, and the group effects of dragload and downdrag versus pile spacing are analyzed. A case study on dragload of a pile group considering with or without couple effect is also presented.
It is worth pointing out that in this experimental condition, when pile-soil relative displacements reach 2 mm, dragload will reaches nearly 75-95% of the maximum values; When consolidation time reaches 240 h, the neutral plane becomes stable approximately at 0.95H (H is the thickness of compression soil). The dragload and downdrag are influenced by load sequence of pile head load versus surcharge load.

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