The aim of this paper is to present through a practical example, some recommendations to properly model confined concrete in three‐dimensional nonlinear finite element analysis. The example chosen is of particular interest for tunneling and structural engineers as it compromises the joints between segments of the concrete lining used with the tunnel boring machine technique. These sections are designed to transmit high pressures, sometimes exceeding the Standards' recommendations. To carry out the nonlinear finite element analyses (NLFEAs) a dedicated software, was employed. A discussion about which parameters play a fundamental role to efficiently model the problem is carried out. Finally, a comparison between NLFEA results and an experimental campaign is presented highlighting the differences in terms of stress values within the steel bars, the failure mechanism and evaluation of the contribution of steel to the resistance of confined concrete.

中文翻译：

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承压混凝土模型在三维非线性有限元分析中的应用：以隧道掘进机衬砌节点为例

本文的目的是通过一个实际的例子，提出一些建议，以便在三维非线性有限元分析中对承压混凝土进行适当的建模。选择的示例对于隧道和结构工程师特别有意义，因为它损害了与隧道掘进机技术一起使用的混凝土衬砌各节之间的接缝。这些部分旨在传递高压，有时会超出标准的建议。为了进行非线性有限元分析（NLFEA），使用了专用软件。进行了有关哪些参数在有效建模问题方面起着基本作用的讨论。最后，我们将NLFEA结果与实验结果进行了比较，着重​​强调了钢筋内应力值的差异，