Banca de QUALIFICAÇÃO: RICARDO AUGUSTO DOS SANTOS HORTA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : RICARDO AUGUSTO DOS SANTOS HORTA
DATA : 03/10/2019
HORA: 15:30
LOCAL: Prédio 12 auditório
TÍTULO:

Rheological behaviour and mechanical properties of cement paste with addition of graphene oxide.

PALAVRAS-CHAVES:

Rheological behavior. Cement composites. Nanomaterials. Graphene oxide.

Mechanical properties

PÁGINAS: 80
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Civil
SUBÁREA: Construção Civil
ESPECIALIDADE: Materiais e Componentes de Construção
RESUMO:

In recent years, the interest of the construction industry and government agencies linked to infrastructure has grown in the development of more durable and higher mechanical performance materials capable of extending the useful life of current structures. These materials include graphene oxide (GO) reinforced cement composites. As a new class of nanomaterial in two-dimensional scale, GO has received great attention in various fields of application in civil engineering due to its high specific surface, good water dispersion, high thermal and electrical conductivity, high modulus of elasticity, as well as superior tensile and flexural strength. The addition of GO allows the partial replacement of cement in cementitious composites, aiming to make them more resistant, durable and with less pollutant load associated with their production. However, it is known that the addition of very thin materials to the cement paste, especially those of nanometer dimensions, may cause the reduction of rheological parameters such as flowability and workability. This work aimed to investigate the changes in rheological behavior, heat of hydration and mechanical properties of Portland cement pastes with GO addition. The resolution procedure for this research objective was divided into two main steps. The first stage consisted of a systemic literature review, which enabled the identification of the best practices adopted in the scientific environment as well as research opportunities related to obtaining cement composites with the addition of GO.The second stage consisted of an experimental program, in which rheology and hydration heat tests were performed on the Portland condiment masses with GO addition and patented at CTNANO (Center for Technology in Nanomaterials of the Federal University of Minas Gerais). For an addition content of 0.03% GO, increases of 39.78% and 20.84% in plastic viscosity and 52.17% and 32.63% in yield stress were observed for pastes prepared with CP. -III and CP-V, respectively. Through the calorimetry test, it was observed that the addition of GO significantly increases the rate of evolution of the hydration heat of the pastes, indicating that it acts as a catalyst for the hydrated calcium silicate formation reaction.It is believed that this research work contributes to the investigation of the potential use of cementitious resources, thus encouraging a consolidation of a new class of nanomaterability capable of promoting greater sustainability in construction.

MEMBROS DA BANCA:
Interno - CONRADO DE SOUZA RODRIGUES
Interna - JUNIA NUNES DE PAULA
Externo à Instituição - JOSÉ MÁRCIO FONSECA CALIXTO - UFMG
Externo à Instituição - MANUEL HOUMARD - UFMG