S. Ozaki¹, D.H. Chen²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 109-116, 2009, DOI:10.3970/icces.2009.009.109

Abstract In the present study, the collapse behavior of a thin-plate subjected to axial compression is investigated parametrically using the finite element method. It is revealed that the axial collapse of the plate, which has various hardening characteristics, is induced by two dominant factors: the stress limitation of the material and the limitation of in-plane deformation at the side edges of the plate. Then, a simplified collapse condition, which corresponds to two modes, is derived based on the plastic buckling theory and the effective width concept, and the validity of the simplified collapse condition is then 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 More >

A. Owatsiriwong¹, B. Phansri¹, K.H. Park^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.31, No.1, pp. 37-60, 2008, DOI:10.3970/cmes.2008.031.037

Abstract This study deals with the particular integral formulation for two (2D) and three (3D) dimensional elastoplastic analyses. The elastostatic equation is used for the complementary solution. The particular integrals for displacement, stress and traction rates are derived by introducing the concept of global shape function to approximate an initial stress rate term of the inhomogeneous equation. The Newton-Raphson algorithm for the plastic multiplier is used to solve the system equation. The developed program is integrated with the pre- and post-processor. The collapse analyses of the smooth flexible strip, square and circular footings are given by More >

M. Thiriet¹, S. Naili², C. Ribreau²

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.3&4, pp. 473-488, 2003, DOI:10.3970/cmes.2003.004.473

Abstract The laminar steady flow of incompressible Newtonian fluid is studied in rigid pipes with cross configuration of a collapsed tube to determine both the entry length and the wall shear stress (WSS). The cross section shapes have been defined from the collapse of an infinitely long elastic tube subjected to an uniform transmural pressure. Five characteristic collapsed configurations, from the unstressed down to the point-contact states, with a finite and infinite curvature radius at the contact point, are investigated, although the wall contact is not necessary observed in veins. Such collapsed shapes induce cross gradient More >

Chengyu Wei^{1, 2}, Deepak Srivastava ², Kyeongjae Cho¹

CMES-Computer Modeling in Engineering & Sciences, Vol.3, No.2, pp. 255-262, 2002, DOI:10.3970/cmes.2002.003.255

Abstract The temperature dependence of the plastic collapse of single-wall carbon nanotubes under axial compression has been studied with classical molecular dynamics simulations using Tersoff-Brenner potential for C-C interactions. At zero temperature, an (8,0) single-wall carbon nanotube under axial compression collapses by forming fins-like structure which remains within the elastic limit of the system, in agreement of previous molecular dynamics study. At finite temperatures, however, we find that temperature dependent fluctuations can activate the formation of sp3 bonds, in agreement with a recently proposed plastic collapse mechanism of the same nanotube with a generalized tight-binding molecular More >

K. Nesnas¹, A. Abdul-Latif²

CMES-Computer Modeling in Engineering & Sciences, Vol.2, No.3, pp. 373-388, 2001, DOI:10.3970/cmes.2001.002.373

Abstract Large plastic collapse of an identical pair of cylinders of various geometries having the same length and volume is studied under lateral compressive load. Superplastic material is employed as a representative material to simulate the classical engineering material behavior under high strain rate. The effects of the strain rate and the geometry of cylinders on the plastic collapse are taken into account. The experimental study is conducted using a structure in which one cylinder is superplastic and the other is steel (referred to as deformable and non-deformable situation "DND''). The actual structure (DND) and that More >