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Mixed finite element analysis of semi-coercive unilateral contact problems with given friction

Ivan Hlaváček (2007)

Applications of Mathematics

A unilateral contact 2D-problem is considered provided one of two elastic bodies can shift in a given direction as a rigid body. Using Lagrange multipliers for both normal and tangential constraints on the contact interface, we introduce a saddle point problem and prove its unique solvability. We discretize the problem by a standard finite element method and prove a convergence of approximations. We propose a numerical realization on the basis of an auxiliary “bolted” problem and the algorithm of...

Mixed finite element approximation of 3D contact problems with given friction : error analysis and numerical realization

Jaroslav Haslinger, Taoufik Sassi (2004)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

This contribution deals with a mixed variational formulation of 3D contact problems with the simplest model involving friction. This formulation is based on a dualization of the set of admissible displacements and the regularization of the non-differentiable term. Displacements are approximated by piecewise linear elements while the respective dual variables by piecewise constant functions on a dual partition of the contact zone. The rate of convergence is established provided that the solution...

Mixed finite element approximation of 3D contact problems with given friction: Error analysis and numerical realization

Jaroslav Haslinger, Taoufik Sassi (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

This contribution deals with a mixed variational formulation of 3D contact problems with the simplest model involving friction. This formulation is based on a dualization of the set of admissible displacements and the regularization of the non-differentiable term. Displacements are approximated by piecewise linear elements while the respective dual variables by piecewise constant functions on a dual partition of the contact zone. The rate of convergence is established provided that the solution...

Mixed formulation for elastic problems - existence, approximation, and applications to Poisson structures

Julian Ławrynowicz, Alain Mignot, Loucas Papaloucas, Claude Surry (1996)

Banach Center Publications

A mixed formulation is given for elastic problems. Existence and uniqueness of the discretized problem are given for conformal continuous interpolations for the stress tensor components and for the components of the displacement vector. A counterpart of the problem is discussed in the case of an even-dimensional Euclidean space with an associated Hamiltonian vector field and the Poisson structure. For conformal interpolations of the same order the question remains open.

Mixed formulations for a class of variational inequalities

Leila Slimane, Abderrahmane Bendali, Patrick Laborde (2004)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

A general setting is proposed for the mixed finite element approximations of elliptic differential problems involving a unilateral boundary condition. The treatment covers the Signorini problem as well as the unilateral contact problem with or without friction. Existence, uniqueness for both the continuous and the discrete problem as well as error estimates are established in a general framework. As an application, the approximation of the Signorini problem by the lowest order mixed finite element...

Mixed formulations for a class of variational inequalities

Leila Slimane, Abderrahmane Bendali, Patrick Laborde (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

A general setting is proposed for the mixed finite element approximations of elliptic differential problems involving a unilateral boundary condition. The treatment covers the Signorini problem as well as the unilateral contact problem with or without friction. Existence, uniqueness for both the continuous and the discrete problem as well as error estimates are established in a general framework. As an application, the approximation of the Signorini problem by the lowest order mixed finite element...

Model problems from nonlinear elasticity: partial regularity results

Menita Carozza, Antonia Passarelli di Napoli (2007)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we prove that every weak and strong local minimizer u ∈ W 1 , 2 ( Ω , ℝ 3 ) of the functional I ( u ) = ∫ Ω | D u | 2 + f ( Adj D u ) + g ( det D u ) , where u : Ω ⊂ ℝ 3 → ℝ 3 , f grows like | Adj D u | p , g grows like | det D u | q and 1<q<p<2, is C 1 , α on an open subset Ω 0 of Ω such that 𝑚𝑒𝑎𝑠 ( Ω ∖ Ω 0 ) = 0 . Such functionals naturally arise from nonlinear elasticity problems. The key point in order to obtain the partial regularity result is to establish an energy estimate of Caccioppoli type, which is based on an appropriate choice of the test functions. The limit case p = q ≤ 2 is also treated for weak local minimizers. ...

Modeling of vibration for functionally graded beams

Gülsemay Yiğit, Ali Şahin, Mustafa Bayram (2016)

Open Mathematics

In this study, a vibration problem of Euler-Bernoulli beam manufactured with Functionally Graded Material (FGM), which is modelled by fourth-order partial differential equations with variable coefficients, is examined by using the Adomian Decomposition Method (ADM).The method is one of the useful and powerful methods which can be easily applied to linear and nonlinear initial and boundary value problems. As to functionally graded materials, they are composites mixed by two or more materials at a...

Currently displaying 61 – 80 of 114