Some numerical verification examples for plane stress elasto-viscoplasticity

This paper presents analytical, semi-analytical and numerical reference examples which can be employed for code verification of elasto-viscoplastic models under plane stress conditions. Mainly because of the overstress function the algorithms traditionally employed in elasto-plastic implementations must be rewritten to correctly impose the plane stress state along with the viscoplastic flow. The viscoplastic formulation presented here considers the strain-rate hardening effects by means of a hardening law that are assumed to have terms depending on the strain rate, which removed can represent a Voce type hardening. The proposed verification tests were employed for the numerical verification of an in-house implementation of the so-called stress-projected procedure inside the finite element method context. Although the focus of this paper is on the stressprojected algorithms the examples presented here can be employed for the verification of other algorithms intended to impose the plane stress state in viscoplasticit

Numerical modeling of strain rate hardening effects on viscoplastic behavior of metallic materials

The main goal of the present work is to provide a finite strain elasticviscoplastic framework to numerically account for strain, strain rate hardening, and viscous effects in cold deformation of metallic materials. The aim is to provide a simple and robust numerical framework capable of modeling the main macroscopic behavior associated with high strain rate plastic deformation of metals. In order to account for strain rate hardening effects at finite strains, the hardening rule involves a rate dependent saturation hardening, and it accounts for linear hardening prevailing at latter deformation stages. The numerical formulation, finite element implementation, and constitutive modeling capabilities are assessed by means of decremental strain rate testing and constant strain rate loading followed by stress relaxation. The numerical results have demonstrated the overall framework can be an efficient numerical tool for simulation of plastic deformation processes where strain rate history effects have to be accounted for

Gendered Path Dependency: Women’s Representation in 20th-century Brazil

This study investigates women’s under-representation in national legislative elections and the gendered legacies embedded in Brazil’s electoral system and party dynamics. Focusing on the historical period prior to the 1996 implementation of a quota law, this article applies a feminist historical institutionalist approach to identify institutions and actors influencing women’s representation. Brazil’s electoral rules for legislative elections, that is, an open-list proportional representation system, remained surprisingly stable throughout periods of regime change and institutional uncertainty in the 20th century. It was not until the return to democracy and the 1986 constituent election that women were able to carve some space in Brazil’s National Congress. This research argues that the relaxing of rules dictating the creation of political parties and the strengthening of women’s movements in the prior decade were influential in creating a propitious moment for increasing the presence of women in national legislative politics

The election and impeachment of Dilma Rousseff, Brazil\u27s first woman president

In October 2010 Dilma Rousseff broke Brazil highest glass ceiling by becoming the country\u27s first woman president. After her re-election in 2014, her government suffered strong opposition both in Congress and on the streets, culminating in her 2016 impeachment. In this talk, I discuss the role gender played in the election of Dilma Rousseff, how being a woman influenced the nomination of cabinet members and policymaking, and the ways in which her gender affected the 2016 impeachment process. By comparing Dilma Rousseff’s presidency with her predecessor and successor, I elaborate on how Brazilian formal political institutions are gendered in a way that benefits men in the electoral process, how women’s leadership is often undermined by the masculine spaces where policymaking is discussed, and how the Brazilian political system undermines the proposal and implementation of feminist and women-centered policies