考虑水土参数变异性的盾构隧道开挖面支护力设计方法OA北大核心

With developments in tunnel engineering,robust design has become essential for ensuring safety and efficiency.This study addressed the limitations of traditional deterministic calculations,which fail to fully account for the spatial variability of geological and hydraulic parameters affecting the stability of the shield tunnel excavation face.Utilizing random field theory,the research incorporated the spatial variability and autocorrelation of stratum parameters.We developed a three-dimensional helical failure mechanism model for uncertain conditions using upper bound analysis and spatial discretization techniques.A novel method for calculating the support force on the shield tunnel face was introduced,integrating the velocity field of the discrete failure mechanism with the power balance equation,and validated against existing studies.The analysis of the impact of parameter uncertainty on failure probability leads to a robust support force design method.Validation of the proposed calculation method for shield tunnel face support force under both deterministic and uncertainty analyses confirms its reliability.The findings show that variability in the pore water pressure coefficient significantly impacts the results,more so than friction angle and cohesion.Increasing the coefficient of variation and autocorrelation distance results in a more dispersed distribution of calculated support forces in stochastic analysis.The proposed robust design approach,validated against engineering data,provides valuable guidance for tunnel construction and design.