The paper focuses on determining lower and upper approximations of the pressure required on the unlined part of a tunnel’s front under drained conditions. This work is carried out within the framework of classic limit analysis. In the last three decades, various approaches have been explored to enhance the understanding of the minimum pressure required for ensuring the stability of the massif during tunnel excavation under drained conditions. Methods for solving this problem are typically categorized as limit equilibrium methods, limit analysis methods, or elasto-plastic stress–strain calculations. However, the failure criterion used has almost invariably been the Mohr–Coulomb criterion. Despite its broad application, this criterion has certain limitations in evaluating the effect of the three principal stresses on the yield of earthy or rocky materials. Over time, alternative failure criteria have been proposed to address this issue, including one developed by Matsuoka and Nakai.

中文翻译：

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使用扩展 Matsuoka-Nakai 屈服准则的浅层隧道排水三维稳定性的下限和上限


本文的重点是确定在排水条件下隧道前部无衬砌部分所需压力的下限和上限近似值。这项工作是在经典极限分析的框架内进行的。在过去的三十年里，人们探索了各种方法，以增强对在排水条件下隧道开挖过程中确保地块稳定性所需的最小压力的理解。解决此问题的方法通常分为极限平衡法、极限分析法或弹塑性应力-应变计算。然而，使用的失效准则几乎总是 Mohr-Coulomb 准则。尽管应用广泛，但该标准在评估三种主要应力对土质或岩石材料产量的影响方面存在一定的局限性。随着时间的推移，已经提出了替代失效标准来解决这个问题，包括 Matsuoka 和 Nakai 开发的失效标准。