Banca de QUALIFICAÇÃO: RENATA BORGES JACOE

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : RENATA BORGES JACOE
DATA : 18/12/2019
HORA: 09:00
LOCAL: CEFET-MG, Campus II, PPGEC
TÍTULO:

 Influence of cement matrix modification on extruded fiber cement production

PALAVRAS-CHAVES:

extrusion, pozzolans, fiber cement, rheology

PÁGINAS: 90
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Civil
SUBÁREA: Construção Civil
ESPECIALIDADE: Materiais e Componentes de Construção
RESUMO:

Natural fiber reinforced cement composites are an alternative to asbestos replacement. However, natural fiber challenges the problems caused by the alkalinity of the cementitious matrix, reducing the durability and long term performance of the composite. The use of pozzolanic mineral additions, such as rice husk ash, has been studied as a treatment for the fiber cement matrix to reduce alkalinity, in addition to refining pore structure, reducing porosity and permeability and increasing mechanical strength and the durability of the composite materials that use this ash. Fiber cement production is by the Hatschek method, which consists of a very fluid mixture of fibers and cement, which is transferred to a belt through rotating rollers creating a sheet of material. Through a vacuum system, part of the water is removed and soon after compacted with a cylinder, and then the material is cut and taken to cure. An alternative method for the production of fiber cement is extrusion, which has lower implantation cost, lower water/cement ratio, similar physical mechanical properties, fibers are oriented, and products can be of various shapes and sizes, and potential use a waste. This work will evaluate the fiber cement production by the extrusion method with the incorporation of rice husk ash in its matrix, which is already studied in the Hatschek method, leading to satisfactory results in terms of mechanical performance and durability when compared to the conventional matrix. Due to the characteristics of rice husk ash it is estimated that a smaller amount of additives will be necessary to ensure the workability of the material. For this purpose, rheological parameters of the cementitious matrix and the fresh composite will be evaluated. It is also proposed to perform accelerated carbonation of the material as a treatment for durability.

MEMBROS DA BANCA:
Presidente - CONRADO DE SOUZA RODRIGUES
Interna - JUNIA NUNES DE PAULA
Externo à Instituição - GUSTAVO HENRIQUE DENZIN TONOLI - UFLA