Banca de QUALIFICAÇÃO: ALEXANDRE NASCIMENTO DE LIMA
Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.STUDENT : ALEXANDRE NASCIMENTO DE LIMA
DATE: 26/04/2024
TIME: 09:00
LOCAL: Universidade Federal de Alagoas
TITLE:
DEVELOPMENT OF A METHODOLOGY FOR OBTAINING HIGH-PERFORMANCE CELLULAR FOAMY CONCRETE
KEY WORDS:
foam cellular concrete; dosage; performance
PAGES: 84
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Construção Civil
SPECIALTY: Materiais e Componentes de Construção
SUMMARY:
In order to overcome the disadvantages of conventional concrete in terms of its high self-weight, lightweight concretes are being used. Foam concrete (FC) is a type of lightweight concrete that can be achieved by incorporating unconnected millimeter-sized air bubbles into its structure, in the fresh state, with a stable foam that resists the stresses of mixing, transportation and casting. This concrete reaches densities of between 400 kg/m3 and 1850 kg/m3, which, in addition to reducing weight, improves acoustic and thermal insulation and increases fire resistance, among other advantages. Despite some disadvantages in terms of mechanical behavior, its use is increasing in the construction industry. Although some FC dosing methods are known and even incorporated into standards, they do not take into account the interactions between the constituent materials of the concrete (mortar) that can affect its performance, leading to a trial and error manufacturing process. The purpose of this work is to propose a dosing methodology for FC that takes into account the materials used and the interactions between them. The idea was to study the effects of the foam formed by the air-entraining admixture in the base paste and the incorporation of the sands into the base paste and cellular paste by means of dosing curves, analyzing their effects on the plastic and hardening properties. Two (2) sands of different grain sizes were used, two (2) cements of different classes, one (1) pozzolanic admixture and one (1) superplasticizing admixture (to improve performance) and um (1) viscosity modifying admixture (to improve the stability of the foams). The development of foam generation using a common laboratory agitator with an adapted probe should be highlighted. The results indicate that the proposed methodology is efficient, regardless of the materials chosen. The influence of the materials used on the properties of the SCC can be clearly seen.
COMMITTEE MEMBERS:
Presidente - 2120767 - PAULO CESAR CORREIA GOMES
Interno(a) - 2544065 - MARCIO ANDRE ARAUJO CAVALCANTE
Externo(a) ao Programa - 3182546 - CASSIA VANESSA ALBUQUERQUE DE MELO - UFALExterno(a) ao Programa - 1121792 - FLAVIO BARBOZA DE LIMA - UFALExterno(a) à Instituição - ROBERTO CESAR DE OLIVEIRA ROMANO