Referência Completa


Título: A damage evolution law for the constitutive modelling of SHCC materials : application to load transfer in pavements
Autor: Edmir José dos Santos Júnior
Programa: Engenharia de Infraestrutura Aeronáutica
Área de Concentração: Infraestrutura Aeroportuária
Orientador : Sérgio Gustavo Ferreira Cordeiro
Ano de Publicação : 2022
Curso : Mestrado Acadêmico
Assuntos : Pavimentos
t Concretos
t Materiais compósitos
t Endurecimento (materiais)
t Deformação plástica
t Plasticidade
t Projeto estrutural
t Engenharia civil
Resumo : The constitutive modeling of cementitious materials is an important subject in structural mechanics. The constitutive modeling of strain-hardening cementitious composites (SHCC), a new class of composite with several engineering applications, can be achieved by damage-plasticity constitutive models. However, the influence of the plastic strains should be properly accounted into the damage evolution laws. In the present work, a new damage evolution law, to be accounted into the concrete damage-plasticity (CDP) constitutive model [1,2], was developed based on uniaxial damage-plasticity stress-strain relationships and energy dissipation concepts. The dissipated energy is considered to contribute for the evolution of the scalar damage variables and the plastic strains. Thus, it is well-suitable to be applied in the constitutive modeling of the SHCC. The definition of the focus points of unloading, available in the literature for SHCC materials in both tension and compression, was adopted to relate the plastic and elastic uniaxial strains. The main advantage of such an approach is that only the monotonic stress-strains experimental envelops are required. The evolution law of the scalar damage variables, as well as the other material parameters for the CDP model, were updated to reproduce three experimental SHCC tests: uniaxial tensile and compressive tests, and a four-point bending test. An application regarding a load transfer devise, widely used in jointed plain cementitious pavements, was studied. The influence of the strain-hardening behavior in the damaged region near transfer device was evaluated. Numerical results of finite element models were compared regarding adequate constitution parameters and evolution laws for both standard concrete and SHCC materials. The numerical results reveal the potential of such an alternative composite material to reduce the pavement damage.
Data de Defesa : 27/05/2022
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