摘要
由于基于单位分解的无网格法,如无网格伽辽金法等,所构造的形函数往往不具有?插值属性,因此难以准确施加本质边界条件和材料边界的连续性条件。而采用传统的罚函数法和拉氏乘子法,分别有合适罚因子的选取和需满足inf-sup条件等问题。所以,利用"局部解满足了要求,则由单位分解所构造的整体解会自动满足要求"的单位分解法的求解性质,通过构造不同类型物理片上的局部解,提出了改进的基于移动最小二乘插值的数值流形法(MLS-NMM),并将其应用于稳定渗流问题的求解中。该方法不仅能直接准确施加本质边界和材料边界条件,而且能精确地求解奇异角点问题。典型算例的计算结果表明,我们所建议的方法是可行的、有效的,可为工程渗流分析提供参考。
Since the shape functions derived from the partition of unity-based meshless method, such as the element-free Galerkin method, are free of the Kronecker delta property, there are great troubles in the exact imposition of the essential boundary condition and boundary continuity of materials. Nevertheless, if adopting the penalty method or the Lagrange multiplier method, problems, like the selection of proper penalty factor and the satisfaction of the inf-sup condition, will occur. This study utilizes the property of partition of unity that once the local solutions satisfy some condition, the global solution will automatically satisfy the same condition. By constructing local approximations in physical patches of different types according to the boundary condition, a new moving least square interpolation-based numerical manifold method(MLS-NMM) is developed. Through the solution of some typical seepage flow problems, it is demonstrated that the proposed procedure is capable to deal with the problems of the singular angular point precisely and may provide an alternative solution for the seepage analysis in engineering.
作者
李伟
郑宏
LI Wei ZHENG Hong(State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China University of Chinese Academy of Sciences, Beijing 100049, China College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2017年第10期1867-1873,共7页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(11172313
11572009
51538001)
国家基础研究计划("973"计划)项目(2014CB047100)
关键词
移动最小二乘插值
数值流形法
单位分解法
非均质
渗流分析
moving least square interpolation
numerical manifold method
partition of unity
heterogeneity
seepage analysis