不同类土的基本力学特性差异性描述  

Differential description of basic mechanical properties of different soils

作　　者：姚仰平[1] 朱丙龙 刘林 YAO Yangping;ZHU Binglong;LIU lin(School of Transportation Science and Engineering,Beihang University,Beijing 100191,China;State Key Laboratory of Building Safety and Built Environment,Beijing 100013,China;Institute of Foundation Engineering,China Academy of Building Research Co.,Ltd.,Beijing 100013,China)

机构地区：[1]北京航空航天大学交通科学与工程学院,北京100191 [2]建筑安全与环境国家重点实验室,北京100013 [3]中国建筑科学研究院有限公司地基基础研究所,北京100013

出　　处：《岩土工程学报》2023年第1期33-46,I0004,共15页Chinese Journal of Geotechnical Engineering

基　　金：国家重点研发计划项目(2018YFE0207100);国家自然科学基金项目(51979001);国家重点基础研究发展计划项目(2014CB047006)。

摘　　要：压硬性、剪胀性和摩擦性为影响土应力应变关系的三大基本力学特性。对于不同种类的土,其三大基本特性既有相似之处也存在区别,相似之处为建立多种土应力应变特性的统一描述提供可能,而区别之处需要本构模型调整参数或构建参量来反映。黏土和砂土的统一硬化模型(CSUH模型)是统一模型中的一个典型代表,模型通过调整压硬性参数p_(s)以定量描述不同土的压硬性差别,通过硬化参量H中的状态参量ξ反映不同密度状态下土的剪胀性差别,通过变换应力方法刻画不同应力洛德角θ时土的强度差别。对比了多组黏土、砂土和堆石料等多种土料试验测量数据与CSUH模型预测数据,结果证明CSUH模型可以针对性地描述不同种类、不同密实度土的应力应变关系。The Compressive hardening,shear dilatancy and friction are the three basic mechanical properties that affect the stress-strain relationship of soils.For different types of soils,there are similarities and differences in the three basic properties.The similarities provide the possibility to establish a unified description for the stress and strain characteristics of various soils,while the differences need to be reflected by adjusting the parameters or constructing the variables in the constitutive model.The unified hardening model(CSUH model) for clays and sands is a typical representative of the unified model.It quantitatively describes the difference in the compressive hardening of different soils by adjusting the compaction hardness parameter p_(s).The difference in the shear dilatancy of soils with different densities can be reflected by applying the state parameter ξ in the hardening parameter H.The difference in the strength of soils under different stress Lode angles θ is described by the transformation stress method.By comparing the measured data of several groups of clay,sand and rockfill with the predicted data of CSUH model,the results show that the CSUH model can describe the stress-strain relationship of different kinds of soils with different densities.

关 键 词：CSUH模型 土的基本特性 差异性 黏土 粒状土 本构模型 

分 类 号：TU431[建筑科学—岩土工程]