Multiscale modeling of large deformation in geomechanics
Multiscale modeling of large deformation in geomechanics
复制标题
地质力学大变形的多尺度建模
DOI：
10.1002/nag.2921
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发表时间：
2019-03
影响因子：
4
通讯作者：
Zhao Jidong
中科院分区：
文献类型：
--
作者：
Liang Weijian;Zhao Jidong
大变形土的行为支撑着各种关键岩土结构的运行和性能，需要在其建模、分析和设计中适当考虑。在处理大变形问题方面，材料点法（MPM）比有限元法（FEM）等传统数值方法得到了越来越广泛的应用。在这项研究中，我们提出了一种新的分层耦合方案，将MPM与离散元法（DEM）相结合，用于地质力学中大变形的多尺度建模。采用点法处理可能发生大变形的典型边值问题，利用DEM推导出点法每个材料点从小应变到有限应变的非线性材料响应。所提出的耦合框架不仅继承了MPM在处理大变形工程问题时相对于FEM的优势（例如，在FEM中不需要重网格以避免网格变形），而且还有助于避免对有限应变下具有高非线性的土的本构材料模型进行复杂的现象学假设。所提出的框架为我们提供了极大的便利，将丰富的颗粒尺度信息和关键的微观力学机制与颗粒土在所有变形水平上的宏观观测联系起来，从初始的小应变阶段到破坏前的大变形阶段。几个经典的地质力学例子被用来展示新的MPM/DEM框架可以提供大变形模拟的关键特征，包括双轴压缩试验、刚性基础、土-管相互作用和土柱倒塌。
Large deformation soil behavior underpins the operation and performance for a wide range of key geotechnical structures and needs to be properly considered in their modeling, analysis, and design. The material point method (MPM) has gained increasing popularity recently over conventional numerical methods such as finite element method (FEM) in tackling large deformation problems. In this study, we present a novel hierarchical coupling scheme to integrate MPM with discrete element method (DEM) for multiscale modeling of large deformation in geomechanics. The MPM is employed to treat a typical boundary value problem that may experience large deformation, and the DEM is used to derive the nonlinear material response from small strain to finite strain required by MPM for each of its material points. The proposed coupling framework not only inherits the advantages of MPM in tackling large deformation engineering problems over the use of FEM (eg, no need for remeshing to avoid mesh distortion in FEM), but also helps avoid the need for complicated, phenomenological assumptions on constitutive material models for soil exhibiting high nonlinearity at finite strain. The proposed framework lends great convenience for us to relate rich grain‐scale information and key micromechanical mechanisms to macroscopic observations of granular soils over all deformation levels, from initial small‐strain stage en route to large deformation regime before failure. Several classic geomechanics examples are used to demonstrate the key features the new MPM/DEM framework can offer on large deformation simulations, including biaxial compression test, rigid footing, soil‐pipe interaction, and soil column collapse.
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影响因子：
2.4
作者：
Gang Wang;Jiangtao Wei
通讯作者：
Gang Wang;Jiangtao Wei
DOI：
10.1002/nag.2406
发表时间：
2016-02
影响因子：
4
作者：
N. Guo;Jidong Zhao
通讯作者：
N. Guo;Jidong Zhao
影响因子：
5.7
作者：
E. Fern;K. Soga
通讯作者：
E. Fern;K. Soga
DOI：
10.1016/0148-9062(74)93043-5
发表时间：
1973
期刊：
Journal of the Soil Mechanics and Foundations Division
影响因子：
--
作者：
A. S. Vesić
通讯作者：
A. S. Vesić
影响因子：
6.3
作者：
J. Brackbill;D. Kothe;H. Ruppel
通讯作者：
J. Brackbill;D. Kothe;H. Ruppel