Abstract The undrained stability of dual circular tunnels buried in spatially random soils is investigated by imposing the random adaptive finite element limit analysis (RAFELA). The emphasis is on quantifying the effect of influential factors including the geometry parameters and spatially variability parameters on the bearing capacity and failure probability of tunnels by assuming a lognormal distribution on undrained shear strength within a spatial correlation structure. Predictions were obtained by the scope enclosed by upper bound (UB) and lower bound results (LB) results within 5% relative errors. To account for a combined effect simultaneously caused by depths of tunnels, spaces between tunnels, soil weights, and spatially variability parameters on the stability of tunnels, all independent variables are involved in parametric studies in pairs. Results revealed several failure patterns and announced how the stability evolves with changes in tunnel geometry and soil spatial variability.

中文翻译：

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空间随机土中双隧道的随机分析

摘要 应用随机自适应有限元分析（RAFELA）研究了埋在空间随机土壤中的双圆隧道不排水稳定性。重点是通过假设空间相关结构内不排水抗剪强度的对数正态分布，量化包括几何参数和空间变异性参数在内的影响因素对隧道承载力和破坏概率的影响。预测是通过由上限 (UB) 和下限结果 (LB) 包围的范围获得的，相对误差在 5% 以内。考虑到隧道深度、隧道间距、土壤重量和空间变化参数对隧道稳定性的综合影响，所有自变量都成对参与参数研究。结果揭示了几种失效模式，并说明了稳定性如何随着隧道几何形状和土壤空间变异性的变化而演变。