复杂加载下统一硬化模型的有限元应用  

APPLICATION OF UNIFIED HARDENING MODEL TO FINITE ELEMENT ANALYSIS UNDER COMPLEX LOADING

作　　者：罗汀[1] 秦振华[1] 姚仰平[1] 万征[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：《工业建筑》2011年第9期8-11,48,共5页Industrial Construction

基　　金：国家自然科学基金项目(50879001;10872016);教育部博士点基金项目(20091102110030)

摘　　要：等幅循环加卸载条件下,经典弹-塑性模型无法描述再加载过程中土体的塑性变形。统一硬化模型参数与Cam-clay模型完全相同,不仅能够描述土的剪缩、剪胀、硬化、软化和应力路径依赖性等特性,而且能够描述循环加载条件下再加载过程中土体发生的塑性变形。通过将UH模型推广应用到复杂加载情况,并进行循环荷载作用下地基承载力有限元的模拟。分析采用Cam-clay模型以及UH模型计算所得的地基的p-s曲线的特点,分析不同深度结点以及横向结点的应力-应变特性。分析表明,UH模型能合理反映复杂加载条件下土的变形特性,有非常好的应用前景。Under the condition of undiminished cyclic loading,the plastic deformation of soil can not be described by using classical elastoplastic models in the reloading process. The UH model can be used to describe many characteristics of clay well, including stress dilatancy, strain hardening and softening, and path dependency behaviour. It can also be used to describe the plastic deformation in the reloading process under the condition of cyclic loading. The UH model was applied under complex stress path condition. The numerical simulation of the bearing capacity of foundation was performed. The p-s curves of the foundation calculated by using the UH model and Camclay model were analyzed. The stress-strain characteristics of nodes at different positions on the surface were analyzed. Based on the results, it was found that the UH model could rationally exhibit the soil behaviors＇under the complex loading condition.

关 键 词：弹-塑性模型 循环加载 地基承载力 有限元分析 

分 类 号：TU43[建筑科学—岩土工程]