To study the deformation response of tunnel excavation in clayey formations, with a specific focus on the time-dependent behavior of the Solignano tunnel. The investigation employs in-situ experimental tests and numerical simulations, utilizing the viscoelastic-viscoplastic strain-softening (VEVP-SS) constitutive model to accurately represent the stress–strain relationship of clayey flysch geomaterials. Creep parameters that align with geological data are obtained through inverse analysis and are used in the VEVP-SS model. Sensitivity analysis was conducted to assess the influence of time and individual model parameters on vertical displacement, identifying primary and secondary influencing factors. Results indicate that the VEVP-SS model is more accurate in simulating vertical displacements induced by creep during the excavation process compared to classical creep models. This is further validated by comparing the model’s output with field measurements from various cross-sections and construction stages. Sensitivity analyses conducted on model parameters reveal their correlations with the tunnel vertical displacement. The study shows a linear increase in tunnel deformation with prolonged creep time, while the rate of increase exhibits a decreasing trend. This comprehensive study provides valuable insights into the behavior of tunnels excavated in clayey formations and underscores the effectiveness of the VEVP-SS model.

中文翻译：

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随时间变化的隧道变形：来自原位测试和数值分析的见解


研究粘土岩层中隧道开挖的变形响应，特别关注 Solignano 隧道的时间依赖性行为。该研究采用原位实验测试和数值模拟，利用粘弹性-粘塑性应变软化 （VEVP-SS） 本构模型来准确表示粘土质 flysch 地质材料的应力-应变关系。与地质数据一致的蠕变参数是通过逆向分析获得的，并用于 VEVP-SS 模型。进行敏感性分析以评估时间和单个模型参数对垂直位移的影响，确定主要和次要影响因素。结果表明，与传统蠕变模型相比，VEVP-SS 模型在模拟挖掘过程中蠕变引起的垂直位移方面更准确。通过将模型的输出与不同横截面和施工阶段的现场测量值进行比较，可以进一步验证这一点。对模型参数进行的敏感性分析揭示了它们与隧道垂直位移的相关性。研究表明，隧道变形随蠕变时间的延长呈线性增加，而增加速率呈下降趋势。这项全面的研究为在粘土岩层中挖掘的隧道的行为提供了有价值的见解，并强调了 VEVP-SS 模型的有效性。