A robust assessment of tunnels due to uncertainties present in soil and ground motion properties can affect the dynamic response of these structures. In this paper, a stochastic analysis considering an aleatory variability in shear velocity Vs by performing Monte Carlo simulations and assessing its influence on underground tunnels. To numerically assess the response of the soil‐tunnel system to near‐fault earthquake ground motion, the required computational domain usually spans multiple kilometers including both earthquake fault and the structure. Thus, these simulations are computationally expensive. An efficient alternative method, that is, the Domain Reduction Method (DRM), in which a modular two‐step methodology for reducing the computational costs in the large domain analysis is employed. A 3‐D soil‐tunnel structure interaction is modeled to simulate the response of tunnel subjected to an inclined earthquake fault. The numerical simulation of the soil‐tunnel‐fault system is conducted in an open‐source FE package called Multi‐hazard Analysis for STOchastic time DOmaiN phenomena (MASTODON) based on MOOSE framework. The interactive analyses are carried out for three distinct types of soils based on National Earthquake Hazards Reduction Program (NEHRP) provision, that is, soft, medium, and hard, by generating 130 realizations. The results provide many insights into the influence of local site effects, that is, frequency shift for the peak response and the importance of input ground motion characteristics that govern the response of underground structures. The dynamic response of the structure is very sensitive to the uncertainty in rock material properties, especially, the stiffness of the rock sample and the shear wave velocity.

中文翻译：

---

使用改进的域缩减方法对近断层地震动中的 3D 隧道进行随机评估

由于土壤和地面运动特性中存在的不确定性，对隧道的稳健评估可能会影响这些结构的动态响应。在本文中，考虑剪切速度 V 的偶然变化的随机分析s通过执行蒙特卡罗模拟并评估其对地下隧道的影响。为了数值评估土壤隧道系统对近断层地震地面运动的响应，所需的计算域通常跨越数公里，包括地震断层和结构。因此，这些模拟的计算成本很高。一种有效的替代方法，即域缩减方法（DRM），其中采用模块化两步方法来降低大域分析中的计算成本。对 3D 土壤-隧道结构相互作用进行建模，以模拟倾斜地震断层下隧道的响应。土壤隧道断层系统的数值模拟是在基于 MOOSE 框架的名为随机时域现象多灾害分析 (MASTODON) 的开源有限元软件包中进行的。根据国家减灾计划 (NEHRP) 的规定，对三种不同类型的土壤（即软土、中土和硬土）进行了交互式分析，生成了 130 个实现。结果提供了许多关于局部场地效应影响的见解，即峰值响应的频移以及控制地下结构响应的输入地震动特征的重要性。结构的动力响应对岩石材料特性的不确定性非常敏感，特别是岩石样本的刚度和剪切波速。