统一硬化模型在复杂加载条件下的应用  

Application of unified hardening model under complex loading

作　　者：侯伟[1] 姚仰平[1] 

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

出　　处：《北京航空航天大学学报》2008年第9期1105-1108,共4页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家自然科学基金资助项目(10672010);国家基础研究计划资助项目(2007CB714203)

摘　　要：超固结土模型是能够描述土的剪缩、剪胀、硬化、软化和应力路径依赖性等特性的简单、实用的模型,与剑桥模型相比,仅增加了一个材料参数(Hvorslev面斜率).采用基于SMP(SpecialyMobilized Plane)强度准则的变换应力方法对模型实现了三维化.在模型中应用加卸载准则来反映复杂加载条件下土体的应力应变特性,模拟了随着循环次数的增加,土体会逐渐变硬,剪切模量逐渐增大、孔隙比减小、超固结程度不断增大等趋势.由循环加载以及真三轴试验数据和预测结果的基本吻合表明了模型能够合理地反映复杂加载条件下土的变形特性.The overconsolidated clay model, a simple and applied model, can describe many characteristics of overconsolidated clays well, including stress-strain relationships, stress dilatancy, strain hardening and softening, and path dependency behaviour. Compared with the Cam-clay model, the overeonsolidated model only requires one additional soil parameter which is the slope of the Hvorslev envelope. Based on the specialy mobilezed plane（SMP） criterion and the corresponding transformed stress tensors, the model ean be applied conveniently to three-dimensional complex stress state. By using the loading criteria, the model can be used to describe that the hardening degree, the shear modulus and the overconsolidated degree increase, and the void ratio decreases with increasing cyclic times under the complex loading. The comparisons between predicted results and test data from the cyclic loading and true triaxial tests show that the model can rationally exhibit the soil behaviors under the complex loading.

关 键 词：超固结土 硬化模型 三维化 复杂加载 

分 类 号：TU411.1[建筑科学—岩土工程]