Study of a stabilized mixed finite element with emphasis in its numerical performance for strain localization problems
Abstract
The numerical performance of a stabilized mixed FE formulation based on the
pressure-gradient-projection method (PGP) using equal-order (linear) interpolation
is evaluated by solving solid mechanics problems, such as structural limit load de-
termination and strain localization modeling. All of them present incompressibility
kinematical constraints induced by the constitutive behavior. This work is specially
devised to obtain critical conclusions about the use of PGP model when the mechan-
ical response is governed by strain softening macroscopic mechanisms. An additional
contribution is the numerical comparative analysis of two different strategies, for
solving the complete linear equation system, addressed to a FE parallel code. The
numerical results are compared with the standard Galerkin formulation and with
an alternative stabilized mixed finite element procedure (PSPG).
pressure-gradient-projection method (PGP) using equal-order (linear) interpolation
is evaluated by solving solid mechanics problems, such as structural limit load de-
termination and strain localization modeling. All of them present incompressibility
kinematical constraints induced by the constitutive behavior. This work is specially
devised to obtain critical conclusions about the use of PGP model when the mechan-
ical response is governed by strain softening macroscopic mechanisms. An additional
contribution is the numerical comparative analysis of two different strategies, for
solving the complete linear equation system, addressed to a FE parallel code. The
numerical results are compared with the standard Galerkin formulation and with
an alternative stabilized mixed finite element procedure (PSPG).