摘要
依托武汉市某深基坑工程,采用PLAXIS 2D软件建立数值模型,分析黏性土和砂性土HSS模型参数的敏感性;对长江一级阶地软土地层的敏感性进行评估,并对显著敏感的参数进行反演。首先,对黏性土和砂性土HSS模型部分参数进行敏感性分析,研究了对隧道拱顶沉降影响最为显著的参数;然后,对长江一级阶地软土地层进行敏感性分析,确定待反演的力学参数;最后,结合既有隧道拱顶沉降的监测数据,通过确定性正反演法对待反演的力学参数进行反演。结果表明:无论是黏性土还是砂性土,对隧道拱顶沉降影响最为显著的参数均为小应变参考初始剪切模量(G_(0)^(ref));长江一级阶地软土地层中,对既有隧道变形影响显著的地层为粉细砂层和细砂层;反演获得的粉细砂层G_(0)^(ref)为90 MPa,细砂层G_(0)^(ref)为120 MPa。
Based on a deep foundation pit project in Wuhan,we establishe a numerical model using the PLAXIS 2D,analyze the sensitivity of HSS model parameters for cohesive and sandy soils,evaluate the sensitivity of soft soil layers in the first terrace of the Yangtze River,and invert the significantly sensitive parameters.Firstly,the sensitivity analysis of certain parameters of the HSS model for cohesive and sandy soils is conducted,focusing on the parameters that most significantly affect the settlement of the tunnel crown.Then,the sensitivity analysis of the soft soil layers in the first terrace of the Yangtze River is carried out to determine the soil mechanical parameters to be inverted.Finally,combining the existing tunnel crown settlement monitoring data,the inversion of the soil mechanical parameters to be inverted is conducted using a deterministic forward-inverse method.The results show that for both cohesive and sandy soils,the parameter that most significantly affects the tunnel crown settlement is the small-strain reference initial shear modulus(G^(ref)_(0)).In the soft soil layers of the first terrace of the Yangtze River,the layers that significantly affect the deformation of the existing tunnel are the silty fine sand layer and the fine sand layer.The inverted G^(ref)_(0)values for the silty fine sand layer and the fine sand layer are 90 MPa and 120 MPa,respectively.
作者
孟超
高志华
黄珏皓
柴少波
刘帅
孙雪兵
MENG Chao;GAO Zhihua;HUANG Juehao;CHAI Shaobo;LIU Shuai;SUN Xuebing(School of Civil Engineering,Chang’an University,Xi’an 710064,China;State Key Laboratory of Geomechanics and Geotechnical Engineering/Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;China Railway Siyuan Survey and Design Group Company Limited,Wuhan 430063,China)
出处
《中山大学学报(自然科学版)(中英文)》
北大核心
2025年第3期139-147,共9页
Acta Scientiarum Naturalium Universitatis Sunyatseni
基金
国家自然科学基金(51909259)。
关键词
HSS模型
深基坑工程
数值模拟
参数
敏感性分析
反演
HSS model
deep excavation engineering
numerical simulation
parameter
sensitivity analysis
inversion
