Damage evolution in brittle coating/substrate structures under three-point bending using discrete element method

Cracking at the fold is a serious issue for many grades of coated paper and coated board. Some recent work has suggested methods to minimize this problem by using two or more coating layers of different properties. A discrete element method (DEM) has been used to model deformation events for single layer coating systems such as in-plain and out-of-plain tension, three-point bending, and a novel moving force picking simulation, but nothing has been reported related to multiple coating layers. In this paper, a DEM model has been expanded to predict the three-point bending response of a two-layer system. The main factors evaluated include the use of different binder systems in each layer and the ratio of the bottom and top layer weights. As in the past, the properties of the binder and the binder concentration are input parameters. The model can predict crack formation that is a function of these two sets of factors. In addition, the model can predict the flexural modulus, the maximum flexural stress, and the strain-at-failure. The predictions are qualitatively compared with experimental results reported in the literature.

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Damage Index Proposals Applied to Quasi-Fragile Materials Simulated Using the Lattice Discrete Element Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.784.209 ◽

2015 ◽

Vol 784 ◽

pp. 209-216 ◽

Cited By ~ 1

Author(s):

Rodolfo S. Rodrigues ◽

Gabriel Birck ◽

Ignacio Iturrioz

Keyword(s):

Discrete Element Method ◽

Strain Localization ◽

Damage Evolution ◽

Damage Index ◽

Discrete Element ◽

Cooperative Effect ◽

Continuous Approach ◽

Damage Process ◽

Natural Way ◽

Element Method

The process of damage in quasi-fragile materials is characterized by loss of isotropy for certain load levels, the strain localization, the cooperative effect between damaged regions and the avalanche of ruptures are particular features in the damage process of this kind of material. This behavior is not easy to represent with a continuous approach. In the present work a version of the Lattice Discrete Element Method (LDEM) is employed. This methodology allows the simulation of fracture and fragmentation in natural way. Different indexes will be shown to perform the measurement of the damage evolution in the context of LDEM. The performance of these indexes to evaluate the damage evolution is discussed in this paper.

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Parametric Study on Strength Characteristics of Two-Dimensional Ice Beam Using Discrete Element Method

Applied Sciences ◽

10.3390/app11188409 ◽

2021 ◽

Vol 11 (18) ◽

pp. 8409

Author(s):

Seongjin Song ◽

Wooyoung Jeon ◽

Sunho Park

Keyword(s):

Bond Strength ◽

Discrete Element Method ◽

Strength Criterion ◽

Discrete Element ◽

Strength Characteristics ◽

Two Dimensional ◽

Three Point Bending ◽

Local Parameters ◽

Compressive Tests ◽

Element Method

Strength characteristics of a two-dimensional ice beam were studied using a discrete element method (DEM). The DEM solver was implemented by the open-source discrete element method libraries. Three-point bending and uniaxial compressive tests of the ice beam were simulated. The ice beam consisted of an assembly of disk-shaped particles with a particular thickness. The connection of the ice particles was modelled using a cuboid element, which represents a bond. If the stress acting on the bond exceeded the bond strength criterion, the bond started to break, explaining the cracking of the ice beam. To find out the effect of the local parameters of the contact and bond models on the ice fracture, we performed numerical simulations for various bond Young‘s modulus of the particles, the bond strength, and the relative particle size ratio.

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Numerical Simulation of Granite Sawing by Discrete Element Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.16-19.1283 ◽

2009 ◽

Vol 16-19 ◽

pp. 1283-1288

Author(s):

Yong Ye ◽

Yuan Li ◽

Xi Peng Xu

Keyword(s):

Discrete Element Method ◽

Discrete Element ◽

Point Of View ◽

Bending Tests ◽

Three Point Bending ◽

Deformation Stage ◽

Initiation And Propagation ◽

Discontinuous Deformation ◽

Sawing Process ◽

Element Method

Granite is a kind of typical discrete material, which experiences from continuous deformation stage, discontinuous deformation stage to fracture stage under sawing forces. Using discrete element method (DEM) to study the process of sawing granite will help us to understand the removal mechanism of granite from the microscopic point of view. In this paper, numerical uniaxial compression and three-point bending tests were conducted to determine the microscopic parameters of the granite specimen firstly, and then simulation was performed for sawing of the specimen. The sawing process, deformation characteristics of granite and the effect of initiation and propagation of cracks on fracture process of granite were investigated. The emphasis was laid on analyzing the variation of sawing forces under different sawing parameters. The simulation results agree well with that of experiments, indicating that DEM can reflect the external macroscopic change of granite by changing the internal microscopic structure. The conclusions in this study would be useful to the modeling of sawing processes and engineering applications.

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Discrete Element Method Simulation of the Damage Evolution in Cross-Ply Laminate under Tensile Loading

Proceedings of the Tenth International Conference on Computational Structures Technology ◽

10.4203/ccp.93.271 ◽

2010 ◽

Author(s):

D.M. Yang ◽

J.Q. Ye ◽

Y.Q. Tan ◽

Y. Sheng

Keyword(s):

Discrete Element Method ◽

Damage Evolution ◽

Tensile Loading ◽

Discrete Element ◽

Discrete Element Method Simulation ◽

Element Method

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Model Establishment of a Co-Based Metal Matrix with Additives of WC and Ni by Discrete Element Method

Materials ◽

10.3390/ma11112319 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2319 ◽

Cited By ~ 1

Author(s):

Xiuyu Chen ◽

Guoqin Huang ◽

Yuanqiang Tan ◽

Hui Huang ◽

Hua Guo ◽

...

Keyword(s):

Discrete Element Method ◽

Metal Matrix ◽

Rupture Strength ◽

Experimental Tests ◽

Discrete Element ◽

Calibration Procedure ◽

Prediction Ability ◽

Three Point Bending ◽

Dem Model ◽

Element Method

A metal matrix is an indispensable component of metal-bonded diamond tools. The composition design of a metal matrix involves a number of experiments, making costly in terms of time, labor, and expense. The discrete element method (DEM) is a potential way to relieve these costs. The aim of this work is to demonstrate a methodology for establishing and calibrating metal matrix’s DEM model. A Co-based metal matrix with WC and Ni additives (CoX–WC–Ni) was used, in which the Co-based metal was Co–Cu–Sn metal (CoX). The skeletal substances in the metal matrix were treated as particles in the model, and the bonding substances were represented by the parallel bond between particles. To describe the elasticity of the metal matrix, a contact bond was also loaded between particles. A step-by-step calibration procedure with experimental tests of three-point bending and compression was proposed to calibrate all microcosmic parameters involved during the establishment of DEM models: first for the CoX matrix, then for the CoX–WC matrix and CoX–Ni matrix, and finally for the CoX–WC–Ni matrix. The CoX–WC–Ni DEM model was validated by the transverse rupture strength (TRS) of two new compositions and the results indicated that the model exhibited a satisfactory prediction ability with an error rate of less than 10%.

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