Yinlong Wang¹, Zhao Li², Ziran Li^1,*, Yang Wang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.2, pp. 1187-1208, 2023, DOI:10.32604/cmes.2022.022596

Abstract The comprehensive tire building and shaping processes are investigated through the finite element method (FEM) in this article. The mechanical properties of the uncured rubber from different tire components are investigated through cyclic loading-unloading experiments under different strain rates. Based on the experiments, an elasto-viscoplastic constitutive model is adopted to describe the mechanical behaviors of the uncured rubber. The distinct mechanical properties, including the stress level, hysteresis and residual strain, of the uncured rubber can all be well characterized. The whole tire building process (including component winding, rubber bladder inflation, component stitching and carcass band folding-back) and the shaping process… More >

Alexander Humer and Hans Irschik^*

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.3, pp. 1395-1417, 2021, DOI:10.32604/cmes.2021.017944

Abstract This paper addresses the application of the continuum mechanics-based multiplicative decomposition for thermohyperelastic materials by Lu and Pister to Reissner’s structural mechanics-based, geometrically exact theory for finite strain plane deformations of beams, which represents a geometrically consistent non-linear extension of the linear shear-deformable Timoshenko beam theory. First, the Lu-Pister multiplicative decomposition of the displacement gradient tensor is reviewed in a three-dimensional setting, and the importance of its main consequence is emphasized, i.e., the fact that isothermal experiments conducted over a range of constant reference temperatures are sufficient to identify constitutive material parameters in the stress-strain relations. We address various isothermal… More >

Zhi Zhang¹, Jianhua Tong^1,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 43-43, 2019, DOI:10.32604/mcb.2019.05721

Abstract Diabetes is a major risk factor to cause macrovascular diseases and plays a pivotal role in aortic wall remodeling. However, the effects of diabetes on elastic properties of aortas remain largely unknown. Thirty adult rabbits (1.6-2.2 kg) were collected and the type I diabetic rabbit model was induced by injection of alloxan. A total of 15 control and 15 diabetic rabbit (abdominal) aortas were harvested. Uniaxial and biaxial tensile tests were performed to measure ultimate tensile strength and to characterize biaxial mechanical behaviors of the aortas. A material model was fitted to the biaxial experimental data to obtain constitutive parameters.… More >

X. Liu, A. Scarpas¹

CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.1, pp. 57-74, 2005, DOI:10.3970/cmes.2005.009.057

Abstract Numerical investigations of strain localization have been performed on 3D dense fully saturated sand specimens subjected to triaxial loading and simultaneous inflow or outflow conditions. The role of the water suction field on the formation and evolution of strain localization is addressed computationally. It has been shown that, in a porous medium, the fluid (water) phase plays indeed an important role in strain localization. The formation and evolution of strain localization are influenced both by the material behaviour of the solid component and the interaction between components. In this contribution, after a presentation of the incremental formulation of the coupled… More >

R. E. Jones^1,*, J. A. Templeton¹, C. M. Sanders¹, J. T. Ostien¹

CMES-Computer Modeling in Engineering & Sciences, Vol.117, No.3, pp. 309-342, 2018, DOI:10.31614/cmes.2018.04285

Abstract We use machine learning (ML) to infer stress and plastic flow rules using data from representative polycrystalline simulations. In particular, we use so-called deep (multilayer) neural networks (NN) to represent the two response functions. The ML process does not choose appropriate inputs or outputs, rather it is trained on selected inputs and output. Likewise, its discrimination of features is crucially connected to the chosen inputoutput map. Hence, we draw upon classical constitutive modeling to select inputs and enforce well-accepted symmetries and other properties. In the context of the results of numerous simulations, we discuss the design, stability and accuracy of… More >

S. Liu¹, X. Liu^2,3, Y. Yuan², H. A. Mang⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.100, No.3, pp. 157-200, 2014, DOI:10.3970/cmes.2014.100.157

Abstract A nonlinear viscoelastic constitutive model for early age concrete is presented in this paper. In this model, time-dependent properties, such as the elastic modulus, and thermal and autogenous shrinkage deformations, are computed by a stochastic multi-scale method, in which three different scales are specified according to the requirement of separation of scales, and different scales are linked by means of the asymptotic expansion theory with the help of specific representative volume elements (RVE). Thus, a cross-scale research from the cement paste to the macro structure of concrete is realized, and performance-based optimization of cement-based materials becomes possible. The developed constitutive… More >

F. Auricchio^{1,2,3,4,1,5,1}, M. Contisup>1,5,S. Morgantisup>1,, A. Reali^1,2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.57, No.3, pp. 225-244, 2010, DOI:10.3970/cmes.2010.057.225

Abstract The use of shape memory alloys (SMA) in an increasing number of applications in many fields of engineering, and in particular in biomedical engineering, is leading to a growing interest toward an exhaustive modeling of their macroscopic behavior in order to construct reliable simulation tools for SMA-based devices. In this paper, we review the properties of a robust three-dimensional model able to reproduce both pseudo-elastic and shape-memory effect; then we calibrate the model parameters on experimental data and, finally, we exploit the model to perform the finite element analysis of pseudo-elastic Nitinol stent deployment in a simplified atherosclerotic artery model. More >

Charles E. Anderson, Jr.¹, Matthew S. Burkins², James D. Walker¹, William A. Gooch²

CMES-Computer Modeling in Engineering & Sciences, Vol.8, No.2, pp. 91-104, 2005, DOI:10.3970/cmes.2005.008.091

Abstract A modification of Wilkins computational ceramics model is used to simulate experiments of the impact of the APM2 bullet against boron carbide/aluminum targets. Flash radiography provides time-resolved penetration histories. The simulation results are compared to the experimental data; generally, agreement is very good, including capturing dwell and then the onset of penetration. Crater width and debris diameter are also reproduced by the simulations reasonably well. A critical discussion of deficiencies of this computational engineering model is provided. More >

J. Ghanbari¹, R. Naghdabadi^1,2

CMC-Computers, Materials & Continua, Vol.10, No.1, pp. 41-64, 2009, DOI:10.3970/cmc.2009.010.041

Abstract Continuum-based modeling of nanostructures is an efficient and suitable method to study the behavior of these structures when the deformation can be considered homogeneous. This paper is concerned about multiscale nonlinear tensorial constitutive modeling of carbon nanostructures based on the interatomic potentials. The proposed constitutive model is a tensorial equation relating the second Piola-Kirchhoff stress tensor to Green-Lagrange strain tensor. For carbon nanotubes, some modifications are made on the planar representative volume element (RVE) to account for the curved atomic structure resulting a non-planar RVE. Using the proposed constitutive model, the elastic behavior of the graphene sheet and carbon nanotube… More >