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Journal of Zhejiang University SCIENCE A

ISSN 1673-565X(Print), 1862-1775(Online), Monthly

Thermo-mechanical behaviour of floating energy pile groups in sand

Abstract: This paper presents the experimental results of small-scale model tests of an instrumented floating energy pile group in which the piles were embedded in dry medium-dense sand and subjected to the seasonal temperature pattern of the city of Nanjing in China. The study also included a model test to assess the effect of including nonthermal piles on the thermo-mechanical behaviour of the floating energy pile group. For comparison, a model test of a single floating energy pile embedded in the same soil and subjected to a similar temperature pattern was also conducted. The results show that the thermo-mechanical behaviour of an energy pile group is different from that of a single energy pile in terms of the thermally induced change in axial pile stress and the displacement of the pile top and tip. This difference in behaviour could be explained by the higher lateral confining pressure expected on a single pile than on a pile in a group due to pile interaction effects, which could lead to different end restraint boundary conditions. We conclude that the thermo-mechanical behaviour of an energy pile is controlled mainly by the end restraint boundary conditions.

Key words: Energy pile; Floating pile; Pile group; Nonuniform thermal; Nonuniform displacement

Chinese Summary  <26> 砂土地基中摩擦型能量桩群桩热力学特性研究

关键词组:能量桩;纯摩擦型桩;群桩;不均匀加热;不均匀沉降


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DOI:

10.1631/jzus.A1700460

CLC number:

TU473.1

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On-line Access:

2018-08-03

Received:

2017-08-29

Revision Accepted:

2018-01-10

Crosschecked:

2018-07-09

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