Canadian Geotechnical Journal, Ahead of Print.
The present study proposes a new finite element methodology to analyse the behaviour of flexible combined pile–raft foundation (CPRF) situated in layered soil, in a displacement-based framework. The soil medium is idealised as an advanced elastic Pasternak medium and the piles and raft are modelled as bar and plate element, respectively. The two components of CPRF are analysed simultaneously and displacement compatibility is satisfied at the pile–raft junctions. A number of soil–structure interaction factors, which govern the behaviour of CPRF, are suitably subsumed in the analysis scheme. The proposed method is validated with available analytical and experimental studies. Further parametric studies, investigating the effects of soil layering and raft flexibility on the behaviour of CPRF, are explored. It is observed that the load sharing proportion between the components and the raft deformation pattern depend upon the thickness and position of the soft soil layer in a multilayered soil system. The thickness of the flexible raft plays a pivotal role in determining the behaviour of CPRF, founded in a multilayered soil profile. Thus, this research manifests notable advancement in understanding the behaviour of flexible CPRF in layered soil.

中文翻译：

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基于位移的有限元方法分析层状土中柔性组合桩筏基础

加拿大岩土工程杂志，印刷前。
本研究提出了一种新的有限元方法来分析基于位移的框架中位于层状土壤中的柔性组合桩筏基础（CPRF）的行为。土壤介质被理想化为先进的弹性帕斯捷尔纳克介质，桩和筏分别被建模为杆和板单元。同时分析 CPRF 的两个组成部分，并在桩筏连接处满足位移兼容性。控制 CPRF 行为的许多土壤-结构相互作用因素都适当地包含在分析方案中。所提出的方法通过现有的分析和实验研究进行了验证。探索了进一步的参数研究，调查土壤分层和筏柔性对 CPRF 行为的影响。据观察，组件之间的载荷分配比例和筏变形模式取决于多层土系统中软土层的厚度和位置。柔性筏的厚度在决定 CPRF 的行为方面起着关键作用，CPRF 建立在多层土壤剖面上。因此，这项研究在理解柔性 CPRF 在层状土壤中的行为方面取得了显着进展。