La méthode de Kikuchi appliquée aux équations de von Karman.
La trave in parete sottile a sezione aperta e variabile: formulazione teorica e risultati sperimentali
Theoretical and experimental results concerning the shear-center of a bent beam with variable section are carried out. The matrix methods of structural analysis for the static linear elastic problem is extended; the stiffness and load matrix are formulated starting from the sectorial areas theory in order to interpret the effect of non-uniform torsion. The formulation may be used through the general matrix displacement method of structural analysis.
Least square method for solving contact problems with friction obeying the Coulomb law
The paper deals with numerical realization of contact problems with friction obeying the Coulomb law. The original problem is formulated as the fixed-point problem for a certain operator generated by the variational inequality. This inequality is transformed to a system of variational nonlinear equations generating other operators, in a sense "close" to the above one. The fixed-point problem of these operators is solved by the least-square method in which equations and the corresponding quadratic...
Linear stability results in a magnetothermoconvection problem.
Locking effects in the finite element approximation of elasticity problems.
Locking free matching of different three dimensional models in structural mechanics
The present paper proposes and analyzes a general locking free mixed strategy for computing the deformation of incompressible three dimensional structures placed inside flexible membranes. The model involves as in Chapelle and Ferent [Math. Models Methods Appl. Sci.13 (2003) 573–595] a bending dominated shell envelope and a quasi incompressible elastic body. The present work extends an earlier work of Arnold and Brezzi [Math Comp.66 (1997) 1–14] treating the shell part and proposes a global...
Locking-Free Finite Elements for Unilateral Crack Problems in Elasticity
We consider mixed and hybrid variational formulations to the linearized elasticity system in domains with cracks. Inequality type conditions are prescribed at the crack faces which results in unilateral contact problems. The variational formulations are extended to the whole domain including the cracks which yields, for each problem, a smooth domain formulation. Mixed finite element methods such as PEERS or BDM methods are designed to avoid locking for nearly incompressible materials in plane elasticity....