Ananthalakshmi K. Iyer¹, A. Rama Chra Murthy², Smitha Gopinath², Nagesh R. Iyer³

CMC-Computers, Materials & Continua, Vol.42, No.3, pp. 227-244, 2014, DOI:10.3970/cmc.2014.042.227

Abstract A non-linear fracture mechanics based approach is proposed to depict a typical fracture mechanism from initiation to growth, eventually leading to failure. This concept is developed for a lightly reinforced beam in flexure. The proposed model integrates the existing methodology of a Stress Intensity Factor equilibrium equation with the bridging forces developed in concrete cover and rebar. The model and solution algorithm outlined presents an elaborate understanding of the mechanism involved and is significant in predicting the behaviour of flexural members. The analysis is performed using MATLAB programming. The proposed approach ensures a maximum tolerable crack length and crack width… More >

G. M. Kulikov¹, S. V. Plotnikova¹

CMC-Computers, Materials & Continua, Vol.23, No.3, pp. 233-264, 2011, DOI:10.3970/cmc.2011.023.233

Abstract This paper presents a robust non-linear piezoelectric exact geometry (EG) four-node solid-shell element based on the higher-order 9-parameter equivalent single-layer (ESL) theory, which permits one to utilize 3D constitutive equations. The term EG reflects the fact that coefficients of the first and second fundamental forms of the reference surface are taken exactly at each element node. The finite element formulation developed is based on a new concept of interpolation surfaces (I-surfaces) inside the shell body. We introduce three I-surfaces and choose nine displacements of these surfaces as fundamental shell unknowns. Such choice allows us to represent the finite rotation piezoelectric… More >

Surkay D. Akbarov^1,2, Resat Kosker³, Nihan T. Cinar³

CMC-Computers, Materials & Continua, Vol.21, No.2, pp. 119-146, 2011, DOI:10.3970/cmc.2011.021.119

Abstract In the present paper, the stress distribution in an infinite elastic body containing two neighboring nanofibers is studied. It is assumed that the midlines of the fibers are in the same plane. With respect to the location of the fibers according to each other the co-phase and anti-phase curving cases are considered. At infinity uniformly distributed normal forces act in the direction of the nanofibers, location. The investigations are carried out in the framework of the piecewise homogeneous body model with the use of the three-dimensional geometrically non-linear exact equations of the theory of elasticity. The normal and shear self-equilibrated… More >

M. Demiral, A. Roy, V. V. Silberschmidt¹

CMC-Computers, Materials & Continua, Vol.19, No.2, pp. 199-216, 2010, DOI:10.3970/cmc.2010.019.199

Abstract Static indentation experiments are typically performed to characterize the mechanical properties of a material of interest by a rigid indenter of known geometry to various depths. In contrast, dynamic indentation of materials has not been fully studied. Evaluating material performance under dynamic loading conditions is a challenge and we demonstrate that various modelling schemes may be appropriate for different flavours of dynamic indentation. In order to compare underlying thermo-mechanics and deformation processes in a static and dynamic indentation process, indentation of a rigid indenter into a workpiece to a fixed chosen penetration is extensively studied. A nonlinear strain rate and… More >

Surkay D. Akbarov^1,2, Resat Kosker³, Yasemen Ucan³

CMC-Computers, Materials & Continua, Vol.17, No.2, pp. 77-102, 2010, DOI:10.3970/cmc.2010.017.077

Abstract In the framework of the piecewise homogeneous body model with the use of the three-dimensional geometrically non-linear exact equations of the theory of elasticity, the method for determination of the stress-strain state in the infinite body containing periodically located row of periodically curved fibers is developed. It is assumed that the midlines of the fibers are in the same plane. With respect to the location of the fibers according to each other the sinphase and antiphase curving cases are considered. Numerical results on the effect of the geometrical non-linearity to the values of the self balanced shear and normal stresses… More >

Chia-Ming Fan^1,2, Chein-Shan Liu³, Weichung Yeih¹, Hsin-Fang Chan¹

CMC-Computers, Materials & Continua, Vol.15, No.1, pp. 67-86, 2010, DOI:10.3970/cmc.2010.015.067

Abstract In this study, the nonlinear obstacle problems, which are also known as the nonlinear free boundary problems, are analyzed by the scalar homotopy method (SHM) and the finite difference method. The one- and two-dimensional nonlinear obstacle problems, formulated as the nonlinear complementarity problems (NCPs), are discretized by the finite difference method and form a system of nonlinear algebraic equations (NAEs) with the aid of Fischer-Burmeister NCP-function. Additionally, the system of NAEs is solved by the SHM, which is globally convergent and can get rid of calculating the inverse of Jacobian matrix. In SHM, by introducing a scalar homotopy function and… More >

Dein Shaw^1,2, Chih-Ren Huang², Li-Cheng Huang²

CMC-Computers, Materials & Continua, Vol.11, No.3, pp. 229-242, 2009, DOI:10.3970/cmc.2009.011.229

Abstract In this study, a method for designing an in-plane, free-form, beam-type spring for use in a lower-limb orthosis was developed. A spring designed by this method follows a predefined relationship between loading and displacement. To facilitate the analysis of the spring, it was divided into several beam segments. The stiffness equations related to loading (including moment and force) and displacements (linear and rotation) of each beam segment were found to follow a modified (non-linear) Castigliano's second theorem (NCST) and were assembled by using the continuity of nodal points of neighbouring curve segments. Using the proposed method, a spring designer can… More >

Eduardo Divo¹, Alain J. Kassab²

CMC-Computers, Materials & Continua, Vol.2, No.4, pp. 277-288, 2005, DOI:10.3970/cmc.2005.002.277

Abstract A Dual Reciprocity Boundary Element Method is formulated to solve non-linear heat conduction problems. The approach is based on using the Kirchhoff transform along with lagging of the effective non-linear thermal diffusivity. A posteriori error estimate is used to provide effective estimates of the temporal and spatial error. A numerical example is used to demonstrate the approach. More >