面向边界面模型的切面算法扩展  

Extension of cutting plane algorithm for a bounding surface model

作　　者：杨杰[1,2,3] 尹振宇 黄宏伟[1,2] 金银富 张冬梅[1,2] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]同济大学地下建筑与工程系,上海200092 [3]南特中央理工大学,法国南特44300

出　　处：《岩土力学》2017年第12期3436-3444,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51579179;No.41372285)~~

摘　　要：保持经典弹塑性本构模型切面算法简单高效的框架,并将其进行扩展,使之适用于边界面类模型的隐式数值计算;通过在算法中引入了确定最大容许步长概念,提出了基于自适应子步迭代的改进切面算法。以一个新改进的结构性黏土边界面模型为例,应用切面算法对其进行了数值实现,并对上海黏土室内试验进行了模拟,验证了切面算法的有效性。然后,通过应用上海黏土参数对在不同固结度下的不排水三轴剪切试验、不排水单剪试验以及不排水三轴循环加载试验和一维压缩试验进行数值计算,初步确定了切面算法的最大容许步长。最后,应用改进切面算法模拟了大步长情况下的不排水单剪试验,验证了所提出的改进算法的计算精度和稳定性。This study aims to extend the scope of cutting plane algorithm for calculating the constitutive equations in the bounding surface model. Moreover, a new algorithm should inherit the simple and efficient framework in the classical elastoplasticity model. The maximum limit of incremental step was employed to propose a modified cutting plane method by using an adaptive sub-stepping algorithm. This method was also applied to an improved bounding surface model for structured clay. Experiments were conducted on Shanghai clay to validate the bounding surface model using the modified method. The validation of the modified method was proven through obtained results. According to parameters of Shanghai clay, numerical studies were also carried out to simulate undrained triaxial tests, undrained simple shear tests, undrained triaxial cyclic tests and oedometer test, respectively. The maximum limit of the incremental step was further determined. Finally, an undrained single shear test was simulated under the large strain step condition by using the modified method. As a result, the accuracy and stability of the modified cutting plane method were verified.

关 键 词：切面算法 边界面模型 弹塑性 最大容许步长 自适应子步迭代 

分 类 号：TU443[建筑科学—岩土工程]