Tianyi Li^1,2, Xin Gu², Qing Zhang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 339-361, 2024, DOI:10.32604/cmes.2024.047566

Abstract This study proposes a comprehensive, coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic differential operator (PDDO), eliminating the need for calibration procedures. The model employs a multi-rate explicit time integration scheme to handle varying time scales in multi-physics systems. Through simulations conducted on granite and ceramic materials, this model demonstrates its effectiveness. It successfully simulates thermal damage behavior in granite arising from incompatible mineral expansion and accurately calculates thermal crack propagation in ceramic slabs during quenching. To account for material heterogeneity, the model utilizes the Shuffle algorithm… More >

Zediao Chen, Feng Liu^*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 2215-2236, 2024, DOI:10.32604/cmes.2023.046618

Abstract Crack propagation in brittle material is not only crucial for structural safety evaluation, but also has a wide-ranging impact on material design, damage assessment, resource extraction, and scientific research. A thorough investigation into the behavior of crack propagation contributes to a better understanding and control of the properties of brittle materials, thereby enhancing the reliability and safety of both materials and structures. As an implicit discrete element method, the Discontinuous Deformation Analysis (DDA) has gained significant attention for its developments and applications in recent years. Among these developments, the particle DDA equipped with the bonded particle model is a powerful… More >

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 >

Jingjing Zhao^1,*, Guangda Lu², Qing Zhang³, Wenchao Du⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 519-539, 2021, DOI:10.32604/cmes.2021.017268

Abstract As a typical brittle material, glass is widely used in construction, transportation, shipbuilding, aviation, aerospace and other industries. The unsafe factors of glass mainly come from its rupture. Thus, establishing a set of prediction models for the cracks growth of glass under dynamic load is necessary. This paper presents a contact damage model for glass based on the ordinary state-based peridynamic theory by introducing a contact force function. The Hertz contact (nonembedded contact) problem is simulated, and the elastic contact force is determined by adjusting the penalty factor. The proposed model verifies the feasibility of penalty-based method to simulate the… More >

Rui Chen^{1, 2}, Yong Wang^{1, 2}, Ruitao Peng^{1, 2, *}, Shengqiang Jiang^{1, 2}, Congfang Hu^{1, 2}, Ziheng Zhao^{1, 2}

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.2, pp. 717-737, 2020, DOI:10.32604/cmes.2020.07438

Abstract An inverse method for parameters identification of discrete element model combined with experiment is proposed. The inverse problem of parameter identification is transmitted to solve an optimization problem by minimizing the distance between the numerical calculations and experiment responses. In this method, the discrete element method is employed as numerical calculator for the forward problem. Then, the orthogonal experiment design with range analysis was used to carry out parameters sensitivity analysis. In addition, to improve the computational efficiency, the approximate model technique is used to replace the actual computational model. The intergeneration projection genetic algorithm (IP-GA) is employed as the… More >

Decheng Feng^{1, 2, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.3, pp. 997-1014, 2020, DOI:10.32604/cmes.2020.07265

Abstract In the present paper, a hierarchical multi-scale method is developed for the nonlinear analysis of composite materials undergoing heterogeneity and damage. Starting from the homogenization theory, the energy equivalence between scales is developed. Then accompanied with the energy based damage model, the multi-scale damage evolutions are resolved by homogenizing the energy scalar over the meso-cell. The macroscopic behaviors described by the multi-scale damage evolutions represent the mesoscopic heterogeneity and damage of the composites. A rather simple structure made from particle reinforced composite materials is developed as a numerical example. The agreement between the fullscale simulating results and the multi-scale simulating… More >

Yongwei Wang¹, Fei Han^2,*, Gilles Lubineau^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.121, No.2, pp. 399-423, 2019, DOI:10.32604/cmes.2019.07192

Abstract Classical continuum mechanics which leads to a local continuum model, encounters challenges when the discontinuity appears, while peridynamics that falls into the category of nonlocal continuum mechanics suffers from a high computational cost. A hybrid model coupling classical continuum mechanics with peridynamics can avoid both disadvantages. This paper describes the hybrid model and its adaptive coupling approach which dynamically updates the coupling domains according to crack propagations for brittle materials. Then this hybrid local/nonlocal continuum model is applied to fracture simulation. Some numerical examples like a plate with a hole, Brazilian disk, notched plate and beam, are performed for verification… More >

A. Brasiliano¹, W.R. Souza², G.N. Doz³, J.L.V. Brito⁴

Structural Durability & Health Monitoring, Vol.4, No.2, pp. 53-66, 2008, DOI:10.3970/sdhm.2008.004.053

Abstract It can be observed that usually, during structures useful life they are submitted to deterioration processes that, depending on the intensity, may affect their performance and load capacity and, as a result, their safety. In this case, it is necessary to accomplish an inspection in order to evaluate the conditions of the structure and to locate and quantify the intensity of the damage. Another important point is to study the behavior of brittle material beams with cracks, as an attempt of understanding the rupture mechanism and crack propagation phenomenon. In this paper, the Residual Error Method (Genovese, 2000) is applied… More >

Cheng Yan, Zhuo-Cheng Oui?a, Zhuo-Ping Duan, Feng-Lei Huang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 83-84, 2011, DOI:10.3970/icces.2011.018.083

Abstract Dynamic behaviors of tensile strength of brittle materials are investigated analytically, and an explicit mathematical expression for the dynamic tensile strength under a quadratic boundary loading is derived, together with the so-called structural-temporal failure criterion. The analytical solution shows reasonably good agreement with the previous dynamic experimental data. Moreover, it is shown by using the explicit expression that the dynamic tensile strength of brittle materials can be determined completely by the quasistatic material parameters such as the quasistatic tensile strength, material density and the incubation-time, which implies that the so-called strain-rate effect on the strength of brittle materials should not… More >

Jorge Daniel Riera¹, Letícia Fleck Fadel Miguel², Ignacio Iturrioz³

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.2, pp. 113-136, 2011, DOI:10.32604/cmes.2011.082.113

Abstract In the truss-like Discrete Element Method (DEM), masses are considered lumped at nodal points and interconnected by means of uni-dimensional elements with arbitrary constitutive relations. In previous studies of the tensile fracture behavior of concrete cubic samples, it was verified that numerical predictions of fracture of non-homogeneous materials using DEM models are feasible and yield results that are consistent with the experimental evidence so far available. Applications that demand the use of large elements, in which extensive cracking within the elements of the model may be expected, require the consideration of the increase with size of the fractured area, in… More >