in this paper, the capabilities of modeling linear viscoelasticty in a finite element method software package (comsol multiphysics) have been investigated. the governing equations of linear viscoelasticity have been developed for 2d cases of plane stress and plane strain. these equations have been verified by solving a related engineering example. since the developed equations are suitable for ...

This study focuses on the optimization of the plane structure. Sequential quadratic programming (SQP) will be utilized, which is one of the most efficient methods for solving nonlinearly constrained optimization problems. A new formulation for the second order sensitivity analysis of the two-dimensional finite element will be developed. All the second order required derivatives will be calculat...

a method for error estimation of isogeometric analysis of plane stress problems which is the based on stress recovery and using the super convergent properties of the gauss points, has been already introduced. this paper is devoted to the development of the method and study of the effects of these supercovergent points on the solution improvement and error estimation of axisymmetric problems by...

An analytical solution is presented for the thermoelastic problem of a half-plane with several cracks under thermo mechanical loading using distributed dislocation technique. The uncoupled quasi-static linear thermoelasticity theory is adopted in which the change in temperature, if any, due to deformations is neglected. The stress field in a half-plane containing thermoelastic dislocation is ob...

the problem of several finite moving cracks in a functionally graded material is solved by dislocation technique under the condition of anti-plane deformation. by using the fourier transform the stress fields are obtained for a functionallygraded strip containing a screw dislocation. the stress components reveal the familiar cauchy singularity at thelocation of dislocation. the solution is empl...

This paper is devoted to study a problem of plane waves reflection at a traction-free surface of a pre-stressed functionally graded piezoelectric material (FGPM). The effects of initial stress and material gradient on the reflection of plane waves are studied in this paper. Secular equation has been derived analytically for the pre-stressed FGPM half-space and used to show the existence of two ...

many metal forming problems have been solved using the slip line field method but all of them have either been two-dimensional (plane strain or plain stress) or axisymmetric problems. in this paper a procedure has been proposed by which the slip line field solution to three dimensional problems of metal forming becomes possible. for this purpose the extrusion of shaped sections has been taken a...

Nomenclature A k , a k Fourier series coefficients, d mean difference between theoretical and experimental stress values, i square root of –1, m mapping function shape descriptor, r, θ polar coordinates in the mapping plane, s standard deviation in the difference between stress values, t distance from the crack tip, x, y Cartesian coordinates in the physical plane, z complex coordinate in the p...

In this paper a numerical approach of the elasto-plastic problem with mixed hardening in the plane stress state, within the classical constitutive framework of small deformation, is proposed. In the formalized problem, the non-zero normal component of the strain (namely, the component in the direction perpendicular to the plane of stress) is considered to be compatible with the plane stress. We...