all the producing and assembling processes exert residual stress on the pieces that may lead to structural failure. therefore, calculating the residual stress in such structures has been common in recent years. in this article, distribution of temperature and residual stress resulting from arc welding in three-pass butt joint in p91 austenitic stainless steel pipes is calculated and estimated u...

Forbidding-enforcing systems (fe-systems) define classes of languages (fe-families) based on boundary conditions. We characterize f -families having not necessarily finite forbidders and prove that none of the Chomsky families of languages can be defined with an fe-system, hence, fe-systems provide a completely new way of defining classes of languages. We show that f -families map to f -familie...

concrete deformation due to temperature and moisture condition will always develop simultaneously and interactively. the environmentally (hygral and thermally) induced stress and deformation are essential to concrete durability. to simulate the deformation of concrete caused by the coupling effect of temperature and moisture, a numerical simulation approach is proposed comprising analytical pro...

The work in this report is motivated by the performance-based engineering approach advocated by PEER. A comprehensive, object-oriented software framework for finite element sensitivity and reliability analysis is developed. The work builds on the existing software OpenSees. An essential ingredient in finite element reliability analysis is accurate, consistent and efficient computation of respon...

We describe and implement a symbolic algebra for scalar and vector-valued finite elements, enabling the computer generation of elements with tensor product structure on quadrilateral, hexahedral and triangular prismatic cells. The algebra is implemented as an extension to the domain-specific language UFL, the Unified Form Language. This allows users to construct many finite element spaces beyon...

Recently there has been growing interest in applying object-oriented approach to large-scale programs with a view to treating the various complexities within these. Software designed using an object-oriented approach can be significantly more robust than traditional software. More codes can be reused and it can be easier to refine, test, maintain and extend the software. Several benefits of thi...

this research work is devoted to the development of a mathematical model for the simulation of the flow of polymeric melts through the die region of extruders. a set of governing equations are solved using finite element method. standard galerkin technique is used in conjunction with the mixed scheme to solve the flow equation. due to the non-linear nature of global equations, the picard iterat...

This paper deals with magnetic modeling of a bearingless synchronous reluctance motor. The motor under consideration includes two separate sets of three-phase windings, one for torque production and the other one for radialforce production. This paper demonstrates by means of finite-element analysis, that it is unrealistic to assume the two three-phase windings to be decoupled from one another....

modelling of crack propagation by finite element method under mixed mode conditions is of prime importance in fracture mechanics. this paper describes an application of finite element method to the analysis of mixed mode crack growth in linear elastic fracture mechanics. crack growth process is simulated by an incremental crack-extension analysis based on the maximum principal stress criterion,...

in recent year, the evolutionary structural optimization (eso) method, has been applied as an effective tool for structures design. the concept of eso method is to use the finite element  results in each iteration of process and removal of inefficient material based on these results. in this method there are several experimental parameters such as rejection rate and evolutionary rate that are e...