软黏土小应变本构模型参数研究与应用  

Investigation and Application of Small-Strain Model Parameters for Soft Clay Deposits

作　　者：王卫东[1,2] 李青 徐中华[1,2] 宗露丹 李耀良[3] Wang Weidong;Li Qing;Xu Zhanghua;Zong Ludan;Li Yaoliang(East China Architecture Design&Research Institute Co.,Ltd.,Shanghai 200011,P.R.China;Shanghai Engineering Research Center of Safety Control for Facilities Adjacent to Deep Excavations,Shanghai 200011,P.R.China;Shanghai Foundation Engineering Co.,Ltd.,Shanghai 200433,P.R.China)

机构地区：[1]华东建筑设计研究院有限公司,上海200011 [2]上海基坑工程环境安全控制工程技术研究中心,上海200011 [3]上海市基础工程有限公司,上海200433

出　　处：《地下空间与工程学报》2023年第3期844-855,共12页Chinese Journal of Underground Space and Engineering

基　　金：上海市科委重点攻关项目(21DZ1204203)。

摘　　要：小应变范围内土体刚度的非线性特性是土体的重要特性之一,合理获取小应变参数对基坑工程周边环境变形分析至关重要。以上海软黏土为例,采集了该地区的典型黏土层(②~⑥层)的原状土样进行了试验研究,提出了由常规岩土勘察报告提供的压缩模量E_(s1-2)确定刚度参数E^(ref)_(oed)、E^(ref)_(50)、E^(ref)_(ur)及小应变剪切模量G^(ref)_(0)的方法,给出了R_(f)、m、ν_(ur)、γ_(0.7)等参数的取值范围,结合勘察报告提供的c′、φ′等强度参数指标,可以合理得到HS-Small模型的全套参数,上述方法及模型参数已被纳入上海市《基坑工程技术标准》。最后,基于该方法确定的小应变模型参数,对上海深隧排水系统云岭西超深竖井基坑进行了三维数值分析,验证了小应变本构模型在超深基坑工程中的适用性。Non-linear stiffness at small strains is one of important intrinsic soil features and is vital to finite element analysis of deep excavations.This paper introduces determination of HS-Small model parameters for typical Shanghai clay layers(②~⑥)through a series of laboratory tests.A method by which stiffness parameters E^(ref)_(oed),E^(ref)_(50),E^(ref)_(ur)and small strain shear modulus G^(ref)_(0)can be deduced from compression modulus Es1-2 has been proposed.The values of parameters R_(f),m,v_(ur),γ_(0.7)are also suggested.Together with shear strength parameters of c′、φ′provided in geotechnical investigation report,the HS-Small model parameters are determined.Finally,Based on the small strain model parameters determined by this method,the three-dimensional numerical analysis of Yunlingxi ultra-deep shaft structure of Shanghai deep tunnel drainage system is carried out,and the applicability of small strain constitutive model in ultra-deep foundation pit engineering is verified.

关 键 词：软黏土 小应变硬化模型 超深圆形基坑 基坑开挖 

分 类 号：TU411[建筑科学—岩土工程]