武汉老黏性土小应变硬化模型参数的试验研究  

Experimental Study on Parameters of HS-Small Model for Natural Aged Clay in Wuhan

作　　者：司马军[1,2] 马旭 潘健 SIMA Jun1,2, MA Xv1, PAN Jian1,3(1. School of Civil Engineering, Wuhan University, Wuhan, Hubei 430072, China ; 2. Hubei Provincial Key Laboratory of Geotechnical and Structural Safety , Wuhan, Hubei 430072, China ; 3.Zhejiang Water Conservancy and Hydropower Survey and Design Institute, Hangzhou, Zhejiang 310002, Chin)

机构地区：[1]武汉大学土木建筑工程学院,湖北武汉430072 [2]岩土与结构工程安全湖北省重点实验室,湖北武汉430072 [3]浙江省水利水电勘测设计院,浙江杭州310002

出　　处：《水利与建筑工程学报》2018年第3期93-97,112,共6页Journal of Water Resources and Architectural Engineering

摘　　要：随着城市建设的迅速发展,基坑环境对变形要求越来越严格。小应变土体硬化模型(HSSmall)能考虑在小应变条件下土体刚度呈非线性变化的特征,逐渐成为城市深基坑数值模拟常用的本构模型之一。推广应用该模型的关键是如何确定不同土体的模型参数。针对武汉地区天然老黏性土,利用高压固结仪和GCTS动三轴仪进行了固结试验、三轴剪切试验和小幅值动三轴试验研究,分别获得了压缩指标、强度参数和小应变刚度。在此基础上,应用PLAXIS软件模拟了三轴固结不排水剪切试验,通过与实测曲线对比进一步修正了HS-Small模型参数。结果表明,HS-Small模型可以较好模拟天然老黏性土峰前应力应变关系,采用低幅值动三轴试验获得小应变刚度是一种值得推广的实用方法。With the development of construction,urban environment is increasingly sensitive to the excavation deformation. The hardening soil model with small strain（ HS-Small） can describe the nonlinear character of soil stiffness under small strain condition. It is becoming one of the most widely used models in numerical simulation of deep excavation in urban area. The key problem of applying the model is how to determine the model parameters for different soils. To study the model parameters of the natural aged clay in Wuhan,which was an over-consolidated stiff soil,several oedometer tests,triaxial tests and dynamic triaxial tests were carried out using the oedometer and the dynamic triaxial instrument. The soil parameters of compression,strength and small strain stiffness were obtained.Based on these parameters,the HS-Small model was applied to simulate the undrained triaxial tests using PLAXIS software. The stress-strain curves obtained from simulation were compared with those of laboratory tests. The results show that the HS-Small model can simulate the pre-peak characteristic of the aged clay,and dynamic triaxial tests with low amplitude might be a practical method to get the small strain stiffness of soil.

关 键 词：天然老黏性土 小应变硬化模型 模型参数 动三轴试验 

分 类 号：TU411[建筑科学—岩土工程]