摘要
隧道施工引发的周围土体变形和地表沉降会对邻近地下结构及地面建筑物产生不利影响。对隧道施工引发土体变形进行数值模拟时,土体本构模型的选择十分重要。基于统一硬化(unified hardening,简称UH)参数的UH模型具有概念清晰、参数较少、实用性强等优势,已服务于多个重大工程。基于考虑小应变范围内弹性剪切模量非线性衰减的UH模型,对伦敦Crossrail隧道在海德公园开挖和衬砌建造施工全过程开展了流固耦合有限元模拟。有限元预测结果与现场实测数据具有较好的吻合,详细分析了隧道施工过程中地表沉降和土体变形规律。最后通过与考虑小应变特性的修正剑桥(modified Cam-clay,简称MCC)模型计算结果比较,进一步验证了UH模型在描述超固结土应力应变特性上的优势。
The deformation of surrounding soils and ground surface settlement induced by tunnel construction can have adverse effects on the adjacent underground structures and buildings.In the numerical simulation of soil deformation due to tunnel construction,the selection of constitutive models for soils is crucial.The UH model was developed based on the unified hardening(UH)parameter,which has the advantage of clear conception,fewer parameters and strong practicability,and has served in several major projects.Based on the UH model which accounts for the nonlinear degradation of elastic shear stiffness at the small strain range,a series of coupled hydro-mechanical(HM)finite element analyses has been carried out for simulating the entire construction process of the Crossrail Tunnel at Hyde Park in London.Comparison between the numerical predictions and field monitoring data exhibits excellent agreement.The predicted features of the ground surface settlement and subsurface vertical and horizontal displacements due to the construction of the Crossrail tunnels are analyzed in detail.Finally,by comparing against the predicted results using the modified Cam-clay(MCC)model accounting for the small strain behaviour,the advantages of the UH model in describing the stress-strain response of heavily overconsolidated clays are further verified.
作者
武孝天
姚仰平
魏然
崔文杰
WU Xiao-tian;YAO Yang-ping;WEI Ran;CUI Wen-jie(School of Transportation Science and Engineering,Beihang University,Beijing 100083)
出处
《岩土力学》
北大核心
2025年第3期1013-1024,1038,共13页
Rock and Soil Mechanics
基金
国家自然科学基金重点项目(No.52238007)
国家自然科学基金项目(No.52479092)
国家自然科学基金项目(No.51979001)
国家重点研发计划资助(No.2018YFE0207100)。
关键词
本构模型
有限元模拟
隧道
沉降
水平位移
constitutive model
finite element analysis
tunnel
settlement
horizontal displacement
