Tao Zhang, Jinglan Deng^*, Jihui Wang

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 545-559, 2020, DOI:10.32604/cmes.2020.09536

Abstract The out-of-plane fold is a common defect of composite materials during the manufacturing process and will greatly affect the compressive strength as well as the service life. Making it of great importance to investigate the influence of out-of-plane defects to the compressive strength of laminate plates of composite materials, and to understand the patterns of defect evolution. Therefore, the strip method is applied in this article to create out-of-plane defects with different aspect ratios in laminated plates of composite materials, and a compressive performance test is conducted to quantify the influence of out-of-plane defects. The result shows that the compressive… More >

Zhen Wang¹, Jonny Rutqvist², Ying Dai¹

CMES-Computer Modeling in Engineering & Sciences, Vol.92, No.6, pp. 539-556, 2013, DOI:10.3970/cmes.2013.092.539

Abstract Fractures in a discrete fracture network can be divided into two parts: Active fractures, which form a connected fracture network and dominate fluid flow and solute transport; and inactive fractures, which are dead-end parts of the fractures (isolated fractures will be incorporated into rock matrix) and do not contribute significantly to the fluid flow, but maybe important for the solute transport, especially for rock matrix diffusion. We present a multi-continuum method (including active fracture continuum, inactive fracture continuum and matrix continuum), which is based on the “multiple interacting continua” method, to describe fluid flow and solute transport in fractured media,… 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 >

G. Minak¹, F. E. G. Chimisso², H. S. Costa Mattos³

Structural Durability & Health Monitoring, Vol.1, No.3, pp. 193-202, 2005, DOI:10.3970/sdhm.2005.001.193

Abstract Cyclic plasticity and damage of a metal matrix composite have been studied in the framework of continuum damage mechanics. The material was considered as macroscopically homogeneous and a model incorporating damage gradient was applied. Strain-controlled fully reversed low-cycle fatigue uniaxial tests were performed to identify material parameters related to yield stress, isotropic and kinematic hardening, fatigue life and damage diffusion. From previous studies it has been found that in the most general case the parameters of the model are constant or depend exponentially on total strain so that only two or three tests are needed for the characterisation. The results… More >

M. Mashayekhi¹, S. Ziaei-Rad², J. Parvizian³, K. Nikbin¹, H. Hadavinia¹

Structural Durability & Health Monitoring, Vol.1, No.1, pp. 67-82, 2005, DOI:10.3970/sdhm.2005.001.067

Abstract The continuum mechanical simulation of microstructural damage process is important in the study of ductile fracture mechanics. An essential feature in these analyses, is the strong influence of stress triaxiality ratio, i.e. the ratio of mean stress to equivalent stress, on the rate of damage growth. In this paper, finite element simulation of damage evolution and fracture initiation in ductile solids will be investigated. A fully coupled constitutive elastic-plastic-damage model has been implemented. The stress update algorithm for the constitutive model is presented together with the consistent tangent operator, which is needed for implicit FEA. Simulations are performed and the… More >

K. Y. Volokh ^{1, 2} , Y. Lev³

Molecular & Cellular Biomechanics, Vol.2, No.1, pp. 27-40, 2005, DOI:10.3970/mcb.2005.002.027

Abstract A simple phenomenological theory of tissue growth is used in order to demonstrate that volumetric growth combined with material anisotropy can lead to accumulation of residual stresses in arteries. The theory is applied to growth of a cylindrical blood vessel with the anisotropy moduli derived from experiments. It is shown that bending resultants are developed in the ring cross-section of the artery. These resultants may cause the ring opening or closing after cutting the artery \textit {in vitro} as it is observed in experiments. It is emphasized that the mode of the arterial ring opening is affected by the parameters… More >

H.S. Wijesinghe¹, N.G. Hadjiconstantinou²

CMES-Computer Modeling in Engineering & Sciences, Vol.5, No.6, pp. 515-526, 2004, DOI:10.3970/cmes.2004.005.515

Abstract We present an implicit hybrid atomisticcontinuum formulation for unsteady, viscous, incompressible flows. The coupling procedure is derived from a domain decomposition method known as the Schwarz alternating method. A dilute gas impulsive Couette flow test problem is used to verify the hybridscheme. Finally, a method to reduce computational costs through limited ensemble averaging is presented. The implicit formulation proposed here is expected to be significantly faster than a time explicit approach based on a compressible formulation for the simulation of low speed flows such as those found in micro- and nano–scale devices. More >

Soon Wan Chung¹, Yoo Jin Choi¹, Seung Jo Kim¹

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.6, pp. 707-718, 2003, DOI:10.3970/cmes.2003.004.707

Abstract In this paper, an automatic finite element remeshing algorithm based on the bubble packing method is utilized for the purpose of numerical simulations of localized damage, because fine meshes are needed to represent the gradually concentrated damage. The bubble packing method introduces two parameters that easily control the remeshing criterion and the new mesh size. The refined area is determined by \textit {a posteriori} error estimation utilizing the value obtained from Superconvergent Patch Recovery. The isotropic ductile damage theory, founded on continuum damage mechanics, is used for this damage analysis. It was successfully shown in the numerical examples (upsetting and… More >

Zhi Sun, Yuxiong Yan

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 117-118, 2011, DOI:10.3970/icces.2011.019.117

Abstract Tower crane is the most generally used construction equipment for civil engineering structures. This paper proposes a method on dynamic modeling and vibration response analysis for high-rise tower cranes in operation. Concerning that tower crane structure is a beam-like lattice structure; a continuum modeling technique is firstly proposed to model the tower crane segment as a box girder element. The modeling based on this element will greatly reduce the number of degrees of freedom for tower crane dynamic analysis and thus improve analyzing efficiency. Based on the equivalent beam model, dynamic response of the tower crane induced by lifting, rotation… More >

Y. Senda, M. Fujio, S. Shimamura, J. Blomqvist, R. M Nieminen

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 93-94, 2011, DOI:10.3970/icces.2011.018.093

Abstract Atomistic molecular dynamics simulation for"polymer melts has been performed inten-sively and revealed the dynamical behavior of atomistic"chain structure in the melt. These atomistic"calculations, however, have been limited by the massive computational costs because of macroscopic properties of long chain polymer. It would be highly de-sirable to use a multiscale approach covering atomistic and macroscopic behavior of the polymer melt. We have developed computational method coupling atomic model and continuum model [1] and applied the method to polymer melt consisted of the long chain polymers. The polymer molecule is coarse-grained into meso-scopic model by so-called spring- beads model. This spring-beads model… More >