Zhiqiang Yang^1,*, Yipeng Rao², Yi Sun¹, Junzhi Cui², Meizhen Xiang^3,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09513

Abstract An effective fracture model is established for the brittle materials with periodic distribution of micro-cracks using the second-order multiscale asymptotic methods. The main features of the model are: (i) the secondorder strain gradient included in the fracture criterions and (ii) the strain energy and the Griffith criterions for micro-crack extensions established by the multiscale asymptotic expansions. Finally, the accuracy of the presented model is verified by the experiment data and some typical fracture problems. These results illustrate that the second-order fracture model is effective for analyzing the brittle materials with periodic distribution of micro-cracks. More >

Zeyuan Zhou, Ming Yu, Xinfeng Wang^*, Zaixing Huang

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.3, pp. 2593-2620, 2023, DOI:10.32604/cmes.2023.027384

Abstract How to simulate fracture mode and crack propagation path in a plate with multiple cracks is an attractive but dicult issue in fracture mechanics. Peridynamics is a recently developed nonlocal continuum formulation that can spontaneously predict the crack nucleation, branch and propagation in materials and structures through a meshfree discrete technique. In this paper, the peridynamic motion equation with boundary traction is improved by simplifying the boundary transfer functions. We calculate the critical cracking load and the fracture angles of the plate with multiple cracks under uniaxial tension. The results are consistent with those predicted by classical fracture mechanics. The… More > Graphic Abstract

Fei Han^*, Zhibin Li, Jianyu Zhang, Zhiying Liu, Chen Yao, Wenping Han

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.3, pp. 2715-2740, 2023, DOI:10.32604/cmes.2023.026922

Abstract In this study, we propose the first unified implementation strategy for peridynamics in commercial finite element method (FEM) software packages based on their application programming interface using the peridynamics-based finite element method (PeriFEM). Using ANSYS and ABAQUS as examples, we present the numerical results and implementation details of PeriFEM in commercial FEM software. PeriFEM is a reformulation of the traditional FEM for solving peridynamic equations numerically. It is considered that the non-local features of peridynamics yet possesses the same computational framework as the traditional FEM. Therefore, this implementation benefits from the consistent computational frameworks of both PeriFEM and the traditional… More >

Zhijian Wu, Li Guo^*, Jun Hong

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.1, pp. 611-636, 2023, DOI:10.32604/cmes.2022.020694

Abstract The local arc-length method is employed to control the incremental loading procedure for phase-field brittle fracture modeling. An improved staggered algorithm with energy and damage iterative tolerance convergence criteria is developed based on the residuals of displacement and phase-field. The improved staggered solution scheme is implemented in the commercial software ABAQUS with user-defined element subroutines. The layered system of finite elements is utilized to solve the coupled elastic displacement and phase-field fracture problem. A one-element benchmark test compared with the analytical solution was conducted to validate the feasibility and accuracy of the developed method. Our study shows that the result… More >

Sai Li¹, Xin Lai^2,*, Lisheng Liu³

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.2, pp. 715-746, 2022, DOI:10.32604/cmes.2022.018544

Abstract In this work, we modeled the brittle fracture of shell structure in the framework of Peridynamics Mindlin-Reissener shell theory, in which the shell is described by material points in the mean-plane with its drilling rotation neglected in kinematic assumption. To improve the numerical accuracy, the stress-point method is utilized to eliminate the numerical instability induced by the zero-energy mode and rank-deficiency. The crack surface is represented explicitly by stress points, and a novel general crack criterion is proposed based on that. Instead of the critical stretch used in common peridynamic solid, it is convenient to describe the material failure by… More >

M. Kumosa¹

Structural Durability & Health Monitoring, Vol.3, No.1, pp. 35-50, 2007, DOI:10.3970/sdhm.2007.003.035

Abstract This paper deals with the structural integrity and durability of suspension composite (non-ceramic, polymer) insulators widely used in power transmission systems around the world. Under certain conditions, the insulators can fail in-service both electrically and mechanically resulting in the drop of energized transmission lines and power outages. In this work, predominantly mechanical failures of the insulators are discussed. In particular, the most important characteristics of a catastrophic failure process called brittle fracture are described. Subsequently, two examples of insulator failures by brittle fracture are shown and their causes explained. Finally, several recommendations on how to avoid brittle fracture as well… More >

D.Taylor¹

Structural Durability & Health Monitoring, Vol.1, No.2, pp. 145-154, 2005, DOI:10.3970/sdhm.2005.001.145

Abstract The Theory of Critical Distances (TCD) is a general term for any of those methods of analysis which use continuum mechanics in conjunction with a characteristic material length constant, L. This paper discusses the use of two simple versions of the TCD: a point-stress approach which we call the Point Method (PM) and a line-average approach: the Line Method (LM). It is shown that they are able to predict the onset of unstable, brittle fracture in specimens of metallic materials containing notches of varying root radii. The approach was successful whatever the micromechanism of crack growth (cleavage or ductile tearing);… More >

M.N.D. Cherief¹, M. Elmeguenni¹, M. Benguediab¹

CMC-Computers, Materials & Continua, Vol.51, No.3, pp. 187-201, 2016, DOI:10.3970/cmc.2016.051.187

Abstract Impact behavior of polymers has received considerable attention in recent years, and much work based on fracture mechanic approaches has been carried out. In this paper, fracture behavior in large deformation of a high density polyethylene (HDPE) materials was investigated through experimental impact testing on single edge notched specimen (SENB) and by using theoretical and analytical fracture criteria concepts. Moreover, a review of the main fracture criteria is given in order to characterize the toughness of this polymer in the both cases (static and dynamic). The fractured specimens obtained from the Charpy impact test were characterized with respect to their… More >

A.N. Guz¹, V.V. Zozulya²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.8, No.4, pp. 151-156, 2008, DOI:10.3970/icces.2008.008.151

Abstract The contact interaction of opposite faces of cracks in 2-D and 3-D solid is studied. The case of a normal time-harmonic wave loading is studied in more details. The distribution of stress intensity factors as functions of the wave number is investigated. The results are compared with those obtained for cracks without allowance for the contact interaction. More >

G.E. Smith¹, A.G. Crocker¹, P.E.J. Flewitt^2,3, S Mahalingam²

CMC-Computers, Materials & Continua, Vol.31, No.1, pp. 17-36, 2012, DOI:10.3970/cmc.2012.031.017

Abstract Three-dimensional models with irregular grain geometries and appropriate physical properties are needed to investigate fracture in polycrystalline metals and alloys. Creating such models is challenging but achievable using a two-stage process, suitable for any polycrystal. The processes described in this paper are illustrated by examples of brittle fracture in ferritic steel, zinc and nickel. The predicted crack path in a model is compared with the grain boundary fracture seen in three point bend specimens of nickel embrittled by sulphur. More >