基于UH模型的盾构隧道非线性地基反力确定方法  

Method for determining nonlinear foundation reaction of shield tunnels based on the UH model

作　　者：梁发云[1] 魏圣明 陈可 袁强 闫静雅[2] 顾晓强[1] LIANG Fayun;WEI Shengming;CHEN Ke;YUAN Qiang;YAN Jingya;GU Xiaoqiang(Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China;Shanghai Shentong Metro Group,Shanghai 200070,China)

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]上海申通地铁集团有限公司,上海200070

出　　处：《岩土工程学报》2025年第2期284-295,共12页Chinese Journal of Geotechnical Engineering

基　　金：上海市优秀技术带头人计划项目(21XD1430900)。

摘　　要：为合理反映堆载作用下盾构隧道地基系数的非线性特征,基于UH模型(统一硬化模型)和MSD方法(mobilizable strength design)提出了一种确定隧道非线性地基反力的方法;并以隧道中心处的土体应力-应变曲线描述全土域的力学行为,提出了预测盾构隧道地基反力的实用简化方法;基于上海第(4)、(5)1层土的UH模型统计参数,将隧道地基反力拟合为双曲线函数形式,进一步将由此获得的初始刚度及极限强度与本构模型参数进行拟合,提出上海地铁盾构隧道的地基反力函数表达式;通过对上海软土盾构隧道堆载工况的多因素分析,验证了该公式对隧道大变形预测问题的实用性。计算结果表明,堆载工况下隧道收敛变形对地基反力曲线的初始刚度要比其极限强度更为敏感,而隧道地基初始刚度主要与土体κ/λ、围压大小等因素相关。To accurately capture its nonlinear characteristics under surcharge,an approach for the subgrade reaction of shield tunnels is implemented on the basis of the soil strength design method(MSD method)and the unified hardening model(UH model).The practical simplified version is proposed by conducting the description of the mechanical properties of the entire soil zone with constitutive curves of soils at the height of tunnel center.Furthermore,using the statistically derived UH constitutive parameters for soil layers④and⑤1 in Shanghai,the subgrade reactions for both soil layers are predicted and fitted by using the hyperbolic curve function.After the secondary fitting process is conducted to obtain the initial stiffness and the ultimate strength in relation to the parameters of the constitutive model,the functions for subgrade reactions of shield tunnels in Shanghai are established.Eventually,the multifactorial evaluation of shield tunnels in Shanghai under surcharge conditions is performed,confirming the capacity of the developed formulas for predicting the large deformation of tunnels under surcharge.The convergence deformation of the tunnels under surcharge is more sensitive to the initial stiffness of subgrade reactions,governed by various soil parameters such asκ/λand confining pressure,than to its ultimate strength.

关 键 词：地基反力曲线 UH模型 MSD方法 堆载 地铁隧道 

分 类 号：TU473[建筑科学—结构工程]