Tianliang Qin¹, Libin Zhao^2,3,*, Jifeng Xu¹, Fengrui Liu^2,3,4, Jianyu Zhang⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.1, pp. 157-176, 2019, DOI:10.31614/cmes.2019.04379

Abstract Progressive damage models (PDMs) have been increasingly used to simulate the failure process of composite material structures. To accurately simulate the damage in each ply, 3D PDMs of composite materials have received more attention recently. A characteristic element length (CEL), which is an important dimensional parameter of PDMs for composite materials, is quite difficult to obtain for 3D elements, especially considering the crack directions during damage propagation. In this paper, CEL models for 3D elements in PDMs of unidirectional composite structures are presented, and their approximate formulae are deduced. The damage in unidirectional composite materials can be divided into fiber… More >

Peixian Li^1,*, Zhixiang Tan², Lili Yan³

CMES-Computer Modeling in Engineering & Sciences, Vol.117, No.2, pp. 231-250, 2018, DOI:10.31614/cmes.2018.02573

Abstract In order to prolong the life cycle of the coal mine, Jinggezhuang (‘JGZ’) coal mine decided to excavate the shaft pillar. The first panel 0091 was designed near the pillar boundary as an experiment in shaft pillar mining. Both probability integral method (PIM) and FLAC^3D were used to evaluate the influence on the shaft safety. PIM parameters were obtained from previous surface subsidence station. The rock property is based on the lab mechanical test. A simulated FLAC^3D model containing shafts and a panel was built based on stratigraphic information. Surface subsidence results of PIM show that the 0091-panel excavation has… More >

Xinyang Cui¹, Qingshuai Ren^1,2, Zihao Li¹, Kun Peng¹, Gaoyang Li^1,3, Zhaoyong Gu¹, Aike Qiao^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.116, No.3, pp. 455-469, 2018, DOI: 10.31614/cmes.2018.04135

Abstract Clinical application of bare metal stents is constrained by the occurrence of in-stent restenosis, mainly due to the complex biomechanical environment in the body. Numerical simulation method was used to evaluate the effect of plaque composition on stent performance in a carotid artery. CT angiography (CTA) data were used as a reference, and zero-load state of the carotid artery was used to establish a 3D stenotic artery model. Different plaque compositions, calcified and hypo-cellular were defined in Model 1 and Model 2, respectively. Interactions between the stents and arterial tissues within the stent crimping-expansion process were analyzed to explore the… More >

Xinyue Liu¹, Yunqiao Liu¹, Xiaobo Gong^1,*, Huaxiong Huang²

CMES-Computer Modeling in Engineering & Sciences, Vol.116, No.2, pp. 281-300, 2018, DOI: 10.31614/cmes.2018.04989

Abstract In this work, a three-dimensional axisymmetric model with nanoparticle, receptor-ligand bonds and cell membrane as a system was used to study the quasi-static receptor-mediated endocytosis process of spherical nanoparticles in drug delivery. The minimization of the system energy function was carried out numerically, and the deformations of nanoparticle, receptor-ligand bonds and cell membrane were predicted. Results show that passive endocytosis may fail due to the rupture of receptor-ligand bonds during the wrapping process, and the size and rigidity of nanoparticles affect the total deformation energy and the terminal wrapping stage. Our results suggest that, in addition to the energy requirement,… More >

Zhengzheng Cao¹, Feng Du^2,3,4, Zhenhua Li², Qinting Wang¹, Ping Xu¹, Haixiao Lin¹

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.3, pp. 275-293, 2017, DOI:10.3970/cmes.2017.113.287

Abstract The stability of ore pillar in mine is essential for the safe and efficient mining. Based on the energy evolvement rule in ore pillar and roadway roof system, the roadway roof and ore pillar are treated as energy release body and energy dissipation body, respectively. Therefore, the double-block mechanical model is established with energy dissipation body and energy release body, and the energy mechanism of ore pillar instability is obtained, based on the fold catastrophe mathematical theory. The research result indicates that the dynamic instability of ore pillar is a physical instability problem caused by the strain softening property of… More >

Meng Li^1,2, Jixiong Zhang^1,3, Nan Zhou¹, Qiang Zhang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.2, pp. 183-194, 2017, DOI:10.3970/cmes.2017.113.189

Abstract To study the influence of coal mining on the stability of river levees, a mechanical model of mining-induced river levee deformation was established. This was based on the mining-induced deformation characteristics of river levees and the application of a typical surface subsidence function. Meanwhile, a failure criterion was proposed for river levees. Using some examples, the deformation of, and stress distribution through, river levees under the influence of mining were obtained: the maximum tensile stress on the bottom of the river levee was less than the tensile strength, under which circumstance the river levee remained undamaged. Meanwhile, this research analyzed… More >

Wei Wei^1,2, Qingsheng Yang^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.112, No.1, pp. 33-58, 2016, DOI:10.3970/cmes.2016.112.033

Abstract Chemo-mechanical coupling behavior of materials is a transformation process between mechanical and chemical energy. In this paper, based on the coupled chemo-mechanical constitutive equations and governing equations during isothermal process, the equivalent integral forms of chemo-mechanical coupling governing equations and corresponding finite element procedure are obtained by using Hamilton's principle. An isoparametric plane element for chemo-mechanical coupling is associated into ABAQUS finite element package through user element subroutine UEL. The numerical examples exhibit that the ionic concentration variation can cause mechanical deformation and mechanical action can produce redistribution of ionic concentration for hydrogels. It is proved that the present developed… More >

Daisuke Ishihara^1,2, Tomoyoshi Horie¹, Tomoya Niho¹, Akiyoshi Baba³

CMES-Computer Modeling in Engineering & Sciences, Vol.108, No.6, pp. 429-452, 2015, DOI:10.3970/cmes.2015.108.429

Abstract In this study, a hierarchal decomposition is proposed to solve the structure- fluid-electrostatic interaction in a microelectromechanical system (MEMS). In the proposed decomposition, the structure-fluid-electrostatic interaction is partitioned into the structure-fluid interaction and the electrostatic field using the iteratively staggered method, and the structure-fluid interaction is split into the structurefluid velocity field and the fluid pressure field using the projection method. The proposed decomposition is applied to a micro cantilever beam actuated by the electrostatic force in air. It follows from the comparisons among the numerical and experimental results that the proposed method can predict the MEMS vibration characteristics accurately. More >

Isa Ahmadi¹, M.M. Aghdam²

CMES-Computer Modeling in Engineering & Sciences, Vol.108, No.1, pp. 21-48, 2015, DOI:10.3970/cmes.2015.108.021

Abstract In this study, a truly meshless method based on the meshless local Petrov-Galerkin method is formulated for analysis of the elastic-plastic behavior of heterogeneous solid materials. The incremental theory of plasticity is employed for modeling the nonlinearity of the material behavior due to plastic strains. The well-known Prandtl-Reuss flow rule of plasticity is used as the constitutive equation of the material. In the presented method, the computational cost is reduced due to elimination of the domain integration from the formulation. As a practical example, the presented elastic-plastic meshless formulation is employed for micromechanical analysis of the unidirectional composite material. A… More >

X. Wang¹, W.T. Ang^1,2, H. Fan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.107, No.2, pp. 81-101, 2015, DOI:10.3970/cmes.2015.107.081

Abstract A micromechanical model is proposed here for estimating the effective stiffness of a pair of parallel microscopically damaged interfaces in a trimaterial under inplane elastostatic deformations. The trimaterial is made of an orthotropic thin layer sandwiched between two orthotropic half-spaces. The microscopically damaged interfaces are modeled using periodically distributed interfacial micro-cracks. The micromechanical model is formulated and numerically solved in terms of hypersingular boundary integro-differential equations. The effects of the width of the thin layer, the micro-crack densities of the two interfaces and the material constants of the thin layer and the two half-spaces on the effective stiffness coefficients are… More >