3-D coupled peridynamics and discrete element method for fracture and post-fracture behavior of soil-like materials
3-D coupled peridynamics and discrete element method for fracture and post-fracture behavior of soil-like materials
复制标题
DOI：
10.1016/j.compgeo.2023.105372
复制
发表时间：
2023-06
影响因子：
5.3
通讯作者：
Y. Fukumoto;Taiki Shimbo
中科院分区：
文献类型：
--
作者：
Y. Fukumoto;Taiki Shimbo
本文研究了一种结合周波理论（PD）和离散单元法（DEM）的三维数值分析方法，该方法可以同时处理假定为土的材料的断裂和断裂后行为。对于地质材料，以连续的方式处理从断裂到断裂后的过程是非常重要的。基于键的PD模型再现了从裂纹萌生到断裂的行为。同时，引入离散元模型，计算破碎后破碎块体间的接触力。还基于离散元解决了墙单元与PD计算节点之间物理接触的计算过程，以便可以使用平面几何边界。对于PD计算节点间连接的破坏准则，引入了双线性粘结模型，以获得从PD到DEM计算过程中的非线性应力应变关系和数值稳定性。为了验证所提出的方法，对无缺陷圆柱试件进行了径向压缩试验的数值模拟，并将计算结果与理论解进行了比较。在此基础上，对多个类土可破碎体的压缩破坏进行了数值模拟，结果表明，该方法可以作为一种三维连续处理类土材料断裂行为的计算框架。
The present paper investigates a 3-D numerical analysis method, combining peridynamics (PD) and the discrete element method (DEM), which can simultaneously handle both the fracture and post-fracture behavior of materials assumed to be soils. With geomaterials, it is very important to treat the process from fracture to post-fracture in a continuous manner. The bond-based PD model is employed to reproduce the behavior from the initiation of cracks to fracturing. At the same time, the DEM model is also introduced so that the contact forces among the fragmented pieces can be calculated after the fracturing. The computational process of the physical contact between the wall element and the computational nodes of the PD is also solved based on the DEM so that plane geometry boundaries can be used. For the failure criteria of the connection between the computational nodes of the PD, a bilinear type of bond model is introduced to obtain a nonlinear stress–strain relationship and numerical stability when the calculation process switches from PD to the DEM. To verify the proposed approach, numerical simulations of the diametral compression test are performed on flawless cylindrical specimens, and the results are compared with theoretical solutions for the stress distribution inside the specimens. Based on the results, a simulation of the compressive failure of multiple soil-like crushable objects is performed as an example of the application of the coupled PD-DEM. The obtained results show that the proposed method will serve as a computational framework that can treat the continuous fracture behavior of soil-like materials in three dimensions.