M.R. Khoshravan¹ and M.A. Setoodeh¹

CMC-Computers, Materials & Continua, Vol.16, No.3, pp. 195-228, 2010, DOI:10.3970/cmc.2010.016.195

Abstract The use of welding to permanently join plates is common in industry due to its high efficiency. But welding creates thermal stresses, which can lead to residual stresses and physical distortion. This phenomenon directly influences the buckling stiffness of the welded structure. The welding distortion not only makes difficult the erection of the project, but also influences the final quality and cost of production. In this research, the thermo-elastic-plastic conditions were simulated by a three-dimensional (3D) finite element model (FE). Mechanical and thermal properties of the material were applied to the model, leading to eigenvalue analysis of the thermal and… More >

Veturia Chiroiu¹, Ligia Munteanu¹, Pier Paolo Delsanto²

CMC-Computers, Materials & Continua, Vol.16, No.1, pp. 75-100, 2010, DOI:10.3970/cmc.2010.016.075

Abstract Conventional continuum theories are unable to capture the observed indentation size effects, due to the lack of intrinsic length scales that represent the measures of nanostructure in the constitutive relations. In order to overcome this deficiency, the Toupin-Mindlin strain gradient theory of nanoindentation is formulated in this paper and the size dependence of the hardness with respect to the depth and the radius of the indenter for multiple walled carbon nanotubes is investigated. Results show a peculiar size influence on the hardness, which is explained via the shear resistance between the neighboring walls during the buckling of the multiwalled nanotubes. More >

E.J. Sapountzakis¹, V.G. Mokos¹

CMC-Computers, Materials & Continua, Vol.12, No.2, pp. 157-196, 2009, DOI:10.3970/cmc.2009.012.157

Abstract In this paper a general solution for the elastic buckling analysis of plates stiffened by arbitrarily placed parallel beams of arbitrary doubly symmetric cross section subjected to an arbitrary inplane loading is presented. According to the proposed model, the stiffening beams are isolated from the plate by sections in the lower outer surface of the plate, taking into account the arising tractions in all directions at the fictitious interfaces. These tractions are integrated with respect to each half of the interface width resulting two interface lines, along which the loading of the beams as well as the additional loading of… More >

D.W. Kelly¹, M.C.W. Lee¹, A.C. Orifici^2,3, R.S.Thomson³, R. Degenhardt^4,5

CMC-Computers, Materials & Continua, Vol.10, No.2, pp. 163-194, 2009, DOI:10.3970/cmc.2009.010.163

Abstract An experimental program for collapse of curved stiffened composite shell structures encountered a wide range of initial and deep buckling mode shapes. This paper presents work to determine the significance of the buckling deformations for determining the final collapse loads and to understand the source of the variation. A finite element analysis is applied to predict growth of damage that causes the disbonding of stiffeners and defines a load displacement curve to final collapse. The variability in material properties and geometry is then investigated to identify a range of buckling modes and development of deep postbuckling deformation encountered in the… More >