T. D. Tran¹, Chien H. Thai^2,3,*, H. Nguyen-Xuan^4,5,*

CMC-Computers, Materials & Continua, Vol.57, No.3, pp. 447-483, 2018, DOI:10.32604/cmc.2018.01738

Abstract A size-dependent computational approach for bending, free vibration and buckling analyses of isotropic and sandwich functionally graded (FG) microplates is in this study presented. We consider both shear deformation and small scale effects through the generalized higher order shear deformation theory and modified couple stress theory (MCST). The present model only retains a single material length scale parameter for capturing properly size effects. A rule of mixture is used to model material properties varying through the thickness of plates. The principle of virtual work is used to derive the discrete system equations which are approximated by moving Kriging interpolation (MKI)… More >

Surkay D. Akbarov^1,2, Hatam H. Guliyev³, Yusif M. Sevdimaliyev⁴, Nazmiye Yahnioglu^5,*

CMC-Computers, Materials & Continua, Vol.55, No.2, pp. 359-380, 2018, DOI:10.3970/cmc.2018.00173

Abstract The paper deals with a development of the discrete-analytical method for the solution of the dynamical problems of a hollow sphere with inhomogeneous initial stresses. The examinations are made with respect to the problem on the natural vibration of the hollow sphere the initial stresses in which is caused by internal and external uniformly distributed pressure. The initial stresses in the sphere are determined within the scope of the exact equations of elastostatics. It is assumed that after appearing this static initial stresses the sphere gets a dynamical excitation and mechanical behavior of the sphere caused by this excitation is… More >

Liang Yang^1,2, Caizhuang Wang^3,*, Shiwei Lin^2,*, Yang Cao², Xiaoheng Liu¹

CMC-Computers, Materials & Continua, Vol.55, No.1, pp. 177-188, 2018, DOI:10.3970/cmc.2018.055.177

Abstract Understanding of metal oxidation is very critical to corrosion control, catalysis synthesis, and advanced materials engineering. Metal oxidation is a very complex phenomenon, with many different processes which are coupled and involved from the onset of reaction. In this work, the initial stage of oxidation on titanium surface was investigated in atomic scale by molecular dynamics (MD) simulations using a reactive force field (ReaxFF). We show that oxygen transport is the dominant process during the initial oxidation. Our simulation also demonstrate that a compressive stress was generated in the oxide layer which blocked the oxygen transport perpendicular to the Titanium… More >

M. Ozisik^1,*, M. A. Mehdiyev², S. D. Akbarov^2,3

CMC-Computers, Materials & Continua, Vol.54, No.2, pp. 103-136, 2018, DOI:10.3970/cmc.2018.054.103

Abstract The dynamics of the moving-with-constant-velocity internal pressure acting on the inner surface of the hollow circular cylinder surrounded by an infinite elastic medium is studied within the scope of the piecewise homogeneous body model by employing the exact field equations of the linear theory of elastodynamics. It is assumed that the internal pressure is point-located with respect to the cylinder axis and is axisymmetric in the circumferential direction. Moreover, it is assumed that shear-spring type imperfect contact conditions on the interface between the cylinder and surrounding elastic medium are satisfied. The focus is on the influence of the mentioned imperfectness… More >

Surkay D. Akbarov^{1, 2, *}, Mahir A. Mehdiyev³

CMC-Computers, Materials & Continua, Vol.54, No.1, pp. 61-81, 2018, DOI:10.3970/cmc.2018.054.061

Abstract The paper develops and employs analytical-numerical solution method for the study of the time-harmonic dynamic stress field in the system consisting of the hollow cylinder and surrounding elastic medium under the non-axisymmetric forced vibration of this system. It is assumed that in the interior of the hollow cylinder the point-located with respect to the cylinder axis, non-axisymmetric with respect to the circumferential direction and uniformly distributed time-harmonic forces act. Corresponding boundary value problem is solved by employing of the exponential Fourier transformation with respect to the axial coordinate and by employing of the Fourier series expansion of these transformations. Numerical… More >

Yi Xue^1,2,3, Faning Dang², Rongjian Li², Liuming Fan², Qin Hao⁴, Lin Mu², Yuanyuan Xia²

CMC-Computers, Materials & Continua, Vol.54, No.1, pp. 43-59, 2018, DOI:10.3970/cmc.2018.054.043

Abstract In the seepage-stress-damage coupled process, the mechanical properties and seepage characteristics of coal are distinctly different between pre-peak stage and post-peak stage. This difference is mainly caused by damage of coal. Therefore, in the process of seepage and stress analysis of coal under the influence of excavation or mining, we need to consider the weakening of mechanical properties and the development of fractures of damaged coal. Based on this understanding, this paper analyzes the influence of damage on mechanics and seepage behavior of coal. A coupled model is established to analyze the seepage-stress-damage coupled process of coal. This model implemented… More >

Arzu Turan Dincel¹, Surkay D. Akbarov^2,3

CMC-Computers, Materials & Continua, Vol.53, No.3, pp. 249-270, 2017, DOI:10.32604/cmc.2017.053.265

Abstract This paper deals with the mathematical modelling and 3D FEM study of the energy release rate (ERR) in the band crack’s front contained in the orthotropic thick rectangular plate which is stretched or compressed initially before the loading of the crack's edge planes. The initial stretching or compressing of the plate causes uniformly distributed normal stress to appear acting in the direction which is parallel to the plane on which the band crack is located. After the appearance of the initial stress in the plate it is assumed that the crack's edge planes are loaded with additional uniformly distributed normal… More >

U. Babuscu Yesil¹

CMC-Computers, Materials & Continua, Vol.53, No.1, pp. 1-22, 2017, DOI:10.3970/cmc.2017.053.001

Abstract Forced and natural vibrations of a rectangular pre-stressed orthotropic composite plate containing two neighboring cylindrical cavities whose cross sections are rectangular with rounded-off corners are investigated numerically. It is assumed that all the end surfaces of the rectangular pre-stressed composite plate are simply supported and subjected to a uniformly distributed normal time-harmonic force on the upper face plane. The considered problem is formulated within the Three-Dimensional Linearized Theory of Elastic Waves in Initially Stressed Bodies (TDLTEWISB). The influence of mechanical and geometrical parameters as well as the initial stresses and the effect of cylindrical cavities on the dynamical characteristics of… More >

J. Solórzano-López¹, F.A. García-Pastor², Angélica Flores-Luna³

CMC-Computers, Materials & Continua, Vol.51, No.3, pp. 203-215, 2016, DOI:10.3970/cmc.2016.051.203

Abstract Shot peening is a widely used technique to improve fatigue life in metallic alloys. This processing technique introduces a subsurface compressive residual stress field through a plastic deformation of the surface caused by the impact of a large number of high-speed projectiles. There are a number of parameters that affect the residual stress field depth and magnitude. The effects of the impact angle, shot speed and shot geometry are currently being researched. In particular, substituting spherical cast shots by cylindrical cut wire shots is an attractive option, especially in terms of cost. The effect of shot geometry on residual stresses,… More >

Xiaoming Zhang¹, Jiangong Yu^1,2, Min Zhang¹, Dengpan Zhang¹

CMC-Computers, Materials & Continua, Vol.48, No.3, pp. 163-179, 2015, DOI:10.3970/cmc.2015.048.163

Abstract The characteristics of the guided waves propagation in functionally graded rods with rectangular cross-section (finite width and height) under initial stress are investigated in this paper based on Biot’s theory of incremental deformation. An extended orthogonal polynomial approach is present to solve the coupled wave equations with variable coefficients. By comparisons with the available results of a rectangular aluminum rod, the validity of the present approach is illustrated. The dispersion curves and displacement profiles of various rectangular functionally graded rods are calculated to reveal the wave characteristics, and the effects of different width to height ratios and initial stress and… More >