Centrifuge Modelling of Tunnelling beneath Axially Loaded Displacement and Non-Displacement Piles in Sand
Centrifuge Modelling of Tunnelling beneath Axially Loaded Displacement and Non-Displacement Piles in Sand
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DOI：
10.1061/9780784480441.060
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发表时间：
2017-03
期刊：
影响因子：
--
通讯作者：
A. Franza;A. Marshall
中科院分区：
文献类型：
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作者：
A. Franza;A. Marshall
在城市地区，在桩基结构下挖掘隧道正变得越来越常见。然而，对于隧道开挖引起的既有桩的沉降量和承载力损失的预测，现有的指导意见有限。本文旨在加深对轴心受荷位移桩和无位移桩对隧道开挖响应的认识。提供了干石英砂中单桩下隧道开挖的一系列土工离心机试验数据。试验在不同的初始安全系数(即初始承载能力与施加荷载的比率)下评估桩的诱导沉降。在此基础上，采用基于空腔扩张理论的分析方法，研究了恒桩荷载作用下残余安全系数随隧道体积损失的变化规律。离心机和分析研究的结果说明了桩的安装方法和初始安全系数的重要性，并加深了对隧道-桩相互作用机理的理解。
Tunnelling under piled structures is becoming more common in urban areas. However, there is limited guidance available for the prediction of settlements and the loss of bearing capacity of existing piles due to tunnel excavation. This paper aims to provide an improved understanding of the response to tunnelling of axially loaded displacement and non-displacement piles. Data are provided from a series of geotechnical centrifuge tests of tunnel excavation beneath single piles in dry silica sand. The tests evaluate induced settlements of the piles at varying levels of initial safety factor (i.e. the ratio between initial bearing capacity and applied load). Furthermore, a previously published analytical approach, based on cavity expansion theory, is used to investigate the variation of the residual safety factor at constant pile load with tunnel volume loss. The outcomes of both centrifuge and analytical investigations illustrate the importance of pile installation method and initial safety factor and improve understanding of tunnel-pile interaction mechanisms.