Implementation of extrinsic cohesive zone model (ECZM) in 2D finite-discrete element method (FDEM) using node binding scheme

Journal Article · 28 April 2023 · Computers and Geotechnics

DOI: https://doi.org/10.1016/j.compgeo.2023.105470 · OSTI ID:1975055

Cai, Weibing ^[1]; Gao, Ke  ^[1]; Ai, Shugang ^[1]; Wang, Min  ^[2]; Feng, Yuntian T.  ^[3]

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1. Southern University of Science and Technology (SUSTech), Shenzhen (China)
2. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
3. Swansea University (United Kingdom)

The combined finite-discrete element method (FDEM) has been widely used for rock fracturing simulations. Conventionally, FDEM is realized using the intrinsic cohesive zone model (ICZM); however, it has the drawback of artificial compliance and high computational expense. As a complement, the extrinsic cohesive zone model (ECZM) is seen to be realized in FDEM recently, whereas the node splitting scheme utilized is cumbersome. Here, within the framework of ICZM-based FDEM, we propose a node binding scheme to efficiently bind the pre-discretized finite elements and thus guarantee the continuum behavior of materials in the elastic stage. The yield surfaces, controlled by ECZM, are dynamically embedded by invoking the pre-inserted cohesive elements. The effectiveness and efficiency of the proposed approach are validated and tested by performing a suite of numerical experiments. Compared with ICZM-based FDEM, the proposed approach can correctly capture material deformation and reduce the computation cost. In contrast to the existing ECZM-based FDEM, the proposed approach can overcome the frequent and complex element topology updating. Finally, this work provides a novel perspective that fully inherits the advantages of both ICZM and ECZM, but circumvents their shortcomings, which guarantees a more efficient and effective simulation of brittle material evolution from continuum to discontinuum.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); Shenzhen Science and Technology Program; Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 1975055
• Report Number(s): LA-UR-23-21801
• Journal Information: Computers and Geotechnics, Vol. 159; ISSN 0266-352X
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English