Search results for "Finite element limit analysis"
showing 10 items of 10 documents
A mixed finite element method for the heat flow problem
1981
A semidiscrete finite element scheme for the approximation of the spatial temperature change field is presented. The method yields a better order of convergence than the conventional use of linear elements.
BEM application on an external problem comparison with both theoretical and finite elements results and observations on divergence strip
1992
Abstract By means of a computer program the Boundary Element Method is applied to a central hole in an undefined plate with uniform load along the boundary. Results are compared with those obtained by Kirsch's theoretical solution and a previous analysis by the Finite Element Method. The calculus of percentage error shows the advantage of the Boundary Element Method on the external problem with regard to the Finite Element Method. The error causes near the boundary internal points are analysed with the existence of a strip, where the result is not reliable in evidence.
A penalty-based finite element interface technology
2002
Abstract An effective and robust interface element technology able to connect independently modeled finite element subdomains is presented. This method has been developed using the penalty constraints and allows coupling of finite element models whose nodes do not coincide along their common interface. Additionally, the present formulation leads to a computational approach that is very efficient and completely compatible with existing commercial software. A significant effort has been directed toward identifying those model characteristics (element geometric properties, material properties and loads) that most strongly affect the required penalty parameter, and subsequently to developing si…
Limit Analysis of Structures with Stochastic Strength Variations∗
1972
Abstract On the basis of a probabilistic fomulation of the fundamental theorems of “limit analysis,” a procedure is developed which allows, with a very limited amount of computing work, the determination of a domain containing the probability distribution curve of the collapse load factor of any structure that satisfies the usual conditions for validity of the limit analysis, but has randomly distributed limit strengths. Further improvements of the bounds thus obtained can be achieved by the equivalent of either the equilibrium or the kinematic methods of limit analysis.
Limit analysis of arch-beam structures by dynamic programming
1974
We study one-dimensional structures like arch-beams in the limit state of plastic collapse, on the ground of a two-dimensional yielding surface (bending moment and normal generalized stress). The proposed method, which is able to give a numerical solution of the problem of finding the limit load, rests on the upper bound theorem of limit analysis and uses dynamic programming. We examine also some questions linked with numerical procedures. A future work devoted to applications will complete the treatment.
A finite element formulation for large deflection of multilayered magneto-electro-elastic plates
2014
An original finite element formulation for the analysis of large deflections in magneto-electro-elastic multilayered plates is presented. The formulation is based on an equivalent single-layer model in which first order shear deformation theory with von Karman strains and quasi-static behavior for the electric and magnetic fields are assumed. To obtain the plate model, the electro-magnetic state is firstly determined and condensed to the mechanical primary variables, namely the generalized displacements. In turn, this result is used to obtain laminate effective stiffness coefficients that allow to express the plate mechanical stress resultants in terms of the generalized displacements and a…
On the numerical solution of axisymmetric domain optimization problems by dual finite element method
1994
Shape optimization of an axisymmetric three-dimensional domain with an elliptic boundary value state problem is solved. Since the cost functional is given in terms of the cogradient of the solution, a dual finite element method based on the minimum of complementary energy principle is used. © 1994 John Wiley & Sons, Inc.
A preliminary comparison between finite element and meshless simulations of extrusion
2009
In this paper the extrusion process of a cross-shaped profile was investigated. In particular, the study was focused on the distortion of extruding profiles when the workpiece and die axis are not aligned. The process was simulated using the finite element method (FEM) and the natural element method (NEM), both implemented in an updated-Lagrangian formulation, in order to avoid the burden associated with the description of free surfaces in ALE or Eulerian formulations. Furthermore, an experimental equipment was developed in order to obtain reliable data in terms of deformed entity, required process load and calculated pressure. At the end, a comparison between the numerical predictions and …
A beam finite element for magneto-electro-elastic multilayered composite structures
2012
Abstract A new finite element based upon an elastic equivalent single-layer model for shear deformable and straight magneto-electro-elastic generally laminated beam is presented. The element has six degrees of freedom represented by the displacement components and the cross-section rotation of its two nodes. The magneto-electric boundary conditions enter the discrete problem as work-equivalent forces and moments while the electro-magnetic state characterization constitutes a post-processing step. The element possesses the superconvergence property for the static problem of beams with uniform cross-section and homogenous material properties along the beam axis direction. Moreover, it is free…
Finite element analysis in vertebrate palaeontology
2002
The Finite Element Analysis (FEA) is a numerical method which allows to analyse the static and dynamic behaviour of complex structures. A structure is substituted by a model consisting of a number of small, well-defined elements, each interconnected by nodes. Within the element attributes and material properties, the model can be exposed to static or dynamic loads. The displacements of the structure as the reaction to its loadings are calculated. Other data such as stress or strain at localized points in the structure are derived from these displacements. Originally developed for engineering, FEA soon was introduced to human medicine by modelling the behaviour of bone, teeth, cartilage and …