考虑土体小应变特性的一种实用本构模型_王海波.pdfVIP

第 28 卷第 6 期 Vol.28 No.6 工 程 力 学 2011 年 6 月 June 2011 ENGINEERING MECHANICS 60 文章编号：1000-4750(2011)06-0060-06 考虑土体小应变特性的一种实用本构模型 * 王海波， 徐 明，宋二祥 (清华大学土木工程系，清华大学结构工程与振动教育部重点实验室，北京 100084) 摘 要：土体小应变刚度特征是准确分析土与结构相互作用的重要因素。土体刚度的衰减速率宜由带有小应变量 测装置的高等三轴实验确定，这制约了土的小应变刚度模型的应用。另外，虽然该类实验在国外已对典型土体进 行了较系统的研究，但是在国内还鲜有报道。该文结合小应变理论，提出了加载为正弦函数和卸载为双曲线形式 的弹塑性模型，并且针对多种土体将模型的计算结果与实验值进行对比，二者的基本符合证明了模型的合理性。 关键词：小应变；应力路径；非线性；刚度；本构模型 中图分类号：TU4 文献标识码：A A PRACTICAL CONSTITUTIVE MODEL OF SOIL CONSDIERING THE BEHAVIOR AT SMALL STRAINS * WANG Hai-bo , XU Ming , SONG Er-xiang (Department of Civil Engineering, Tsinghua University, Key Laboratory for Structure Engineering and Vibration of Ministry of Education, Tsinghua University, Beijing 100084, China) Abstract: It is important to consider the small-strain stiffness of soil in analyzing the interaction between soil and structures. The attenuation rate of soil stiffness should be determined through advanced triaxial test with local strain measurement device, which restricts the application of small strain model. Although systematic study of typical soils has been carried out abroad through such experiments, it is rarely reported in China. This paper proposes an elasto-plastic constitutive model with sine function and hyperbolic function to simulate the stress-strain relations during loading and unloading respectively. The calculated results using the proposed model for a variety of soils are compared with experimental data and good agreement is found, which proves the