P. Zhao¹, G. Shi^1,2

CMC-Computers, Materials & Continua, Vol.22, No.2, pp. 147-168, 2011, DOI:10.3970/cmc.2011.022.147

Abstract The Poisson ratio is a very important mechanical parameter for both single-walled carbon nanotubes (SWCNTs) and graphene. But, the Poisson ratios of SWCNTs and graphene can not be determined by the direct measurement on the nanoscale specimen, and Poisson ratios of SWCNTs and graphene predicted by different models vary in a huge range. An improved molecular structural mechanics model, where the bond angle variations are modeled by the flexible connections of framed structures, is employed in this paper to predict the Poisson ratios of SWCNTs and monolayer graphene sheets. The present results indicate that the Poisson ratios of both SWCNTs… More >

Yong Kou¹, Ke Jin¹, Xiaojing Zheng^1,2

CMC-Computers, Materials & Continua, Vol.22, No.2, pp. 129-146, 2011, DOI:10.3970/cmc.2011.022.129

Abstract Magnetic shielding needs to be employed to ensure proper operation of some electronic equipment which are sensitive to external magnetic interference, such as cryogenic valves located inside the ITER feeder cubicles. This paper is concerned with the shielding efficiency of the magnetic shielding enclosures. A 3-D theoretical model for Fe-Ni alloy magnetic shielding enclosures based on finite element method (FEM) is obtained with the nonlinear law of magnetization. The influence of shielding materials, enclosure configurations, single or multi- layer designs, and apertures on the shielding efficiency is investigated. It is shown that the proposed model can predict the shielding efficiency… More >

M.F. Liu¹

CMC-Computers, Materials & Continua, Vol.22, No.2, pp. 97-128, 2011, DOI:10.3970/cmc.2011.022.097

Abstract A new invented Orthogonal Tapered Beam Functions (OTBFs) have been introduced in this paper and used in accordance with the Rayleigh-Ritz method to determine the natural frequencies and mode shapes of the non-uniform rectangular isotropic plates with varying thickness in one or two directions. The generation of the OTBFs is based on the static solution of a one-dimensional beam problem subjected to constant applied load, and then extends to an orthogonal or orthonomal infinite set of admissible functions by performing the three-term recurrence scheme. A wide range of non-uniform rectangular plate whose domain is referenced by a so-called truncation factor… More >

Cheng Wang¹, Jianguo Ning¹, Tianbao Ma¹

CMC-Computers, Materials & Continua, Vol.22, No.1, pp. 73-96, 2011, DOI:10.3970/cmc.2011.022.073

Abstract In this paper, we report high resolution simulations using a fifth-order weighted essentially non-oscillatory (WENO) scheme with a third-order TVD Runge-Kutta time stepping method to examine the features of the detonation for gas and condensed explosives. A two-stage chemical reaction model and an ignition and growth model are employed to describe the chemical reaction process for gas and condensed explosives. Based on the Steger-Warming vector flux splitting method, a splitting method is employed when the vector flux does not satisfy the homogeneity property for simulating detonation wave propagation for condensed explosives. The sensibility of flame propagation process and explosion overpressure… More >

Smitha Gopinath^1,2, A. Ramach,ra Murthy¹, Nagesh R. Iyer¹

CMC-Computers, Materials & Continua, Vol.22, No.1, pp. 55-72, 2011, DOI:10.3970/cmc.2011.022.055

Abstract This paper presents the mathematical modeling techniques for nonlinear finite element analysis of RC structure to incorporate uniform corrosion effects. Effect of corrosion has been simulated as reduction in effective cross-sectional area of reinforcing bar, reduction in bonding phenomena and as reduction in material properties of reinforcing bar such as yield strength and elastic modulus. Appropriate constitutive laws for (i) corroded rebar elements and (ii) bond slip with corroded bar have been described. Procedure has been outlined to determine the global damage indicator by secant stiffness based approach. A corroded RC beam has been analysed to validate the proposed model… More >

S. Gao¹, K. Nakasa², K. Nogi³, L. Huang⁴

CMC-Computers, Materials & Continua, Vol.22, No.1, pp. 39-54, 2011, DOI:10.3970/cmc.2011.022.039

Abstract An incremental press-forming method was newly developed for the fabrication of spiral plates of a continuous screw conveyer, boring screw, screw pump and so on. In this method, a pair of V-shaped punches and dies with two opposite inclined edges are used instead of punch and die with spiral surfaces. The experiments on incremental forming were carried out on aluminum alloy and steel disks with a hole and a slit, and the deformation process of the plate during and after the press-forming was simulated by a finite element method (FEM). The press-forming shows that the spiral plate has a correct… More >

S. D. Akbarov^1,2, S. Karakaya³

CMC-Computers, Materials & Continua, Vol.22, No.1, pp. 1-38, 2011, DOI:10.3970/cmc.2011.022.001

Abstract The 3D approach was employed for investigations of the stability loss of the solid circular cylinder made from viscoelastic composite material. This approach is based on investigations of the evolution of the initial infinitesimal imperfections of the cylinder within the scope of 3D geometrically nonlinear field equations of the theory of viscoelasticity for anisotropic bodies. The numerical results of the critical forces and critical time are presented and discussed. To illustrate the importance of the results obtained using the 3D approach, these results are compared with the corresponding ones obtained by employing various approximate beam theories. The viscoelasticity properties of… More >

Wenqing Wang¹, Thomas Schnicke², Olaf Kolditz³

CMC-Computers, Materials & Continua, Vol.21, No.3, pp. 217-236, 2011, DOI:10.3970/cmc.2011.021.217

Abstract This work focuses on parallel finite element simulation of thermal hydraulic and mechanical (THM) coupled processes in porous media, which is a common phenomenon in geological applications such as nuclear waste repository and CO2 storage facilities. The Galerkin finite element method is applied to solve the derived partial differential equations. To deal with the coupling terms among the equations, the momentum equation is solved individually in a monolithic manner, and moreover their solving processes are incorporated into the solving processes of nonisothermal hydraulic equation and heat transport equation in a staggered manner. The computation task arising from the present method… More >

Zhao Huiming¹, Dong Zhengzhu¹, Chen Jiarui¹, Yang Min¹

CMC-Computers, Materials & Continua, Vol.21, No.3, pp. 209-216, 2011, DOI:10.3970/cmc.2011.021.209

Abstract The advantages of coupling of a natural boundary element method and a finite element method are introduced. Then we discuss the principle of the direct coupling of NBEM and FEM and its implementation. The comparison of the results between the direct coupling method and FEM proves that the direct coupling method is simple, feasible and valid in practice. More >

Zhuo-Jia Fu^1,2, Wen Chen¹, Qing-Hua Qin^2,3

CMC-Computers, Materials & Continua, Vol.21, No.3, pp. 187-208, 2011, DOI:10.3970/cmc.2011.021.187

Abstract This paper presents a hybrid finite element model (FEM) with a new type of general solution as interior trial functions, named as HGS-FEM. A variational functional corresponding to the proposed general solution is then constructed for deriving the element stiffness matrix of the proposed element model and the corresponding existence of extremum is verified. Then the assumed intra-element potential field is constructed by a linear combination of novel general solutions at the points on the element boundary under consideration. Furthermore, the independent frame field is introduced to guarantee the intra-element continuity. The present scheme inherits the advantages of hybrid Trefftz… More >