Banca de DEFESA: DAIANE TELLES DA SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : DAIANE TELLES DA SILVA
DATA : 31/03/2021
HORA: 14:00
LOCAL: Porto Velho
TÍTULO:

USE OF CALCINATED CLAYS FOR PARTIAL REPLACEMENT OF PORTLAND CEMENT IN CONCRETE MIXTURES

PALAVRAS-CHAVES:

Portland Cement, Pozzolans, Concrete, Environment.

PÁGINAS: 48
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Civil
SUBÁREA: Estruturas
ESPECIALIDADE: Estruturas de Concreto
RESUMO:

The human evolution process are constant and inevitable, mainly when it comes to society infrastructure development. Following this development, there is a very old origin material and has been used until today, the Portland cement. This material is still manufactured with a very aggressive process to the environment, mainly by nature extractions and CO₂ emissions into the atmosphere. This highly impacting process for the environment has meant that many researches have been and are still being developed, aiming to find alternative materials to cement. To replace Portland cement, much has been studied about the materials calcination in order to obtain pozzolans. In this regard, this paper seeks to evaluate the pozzolanic potential of clays from deposits in Rondonia state, in order to replace cement in different percentages within concrete mixtures and subsequently analyze its compressive strength characteristics through parameters established by regulatory standards. The employed method was the clay samples treatment, calcination of these in a muffle furnace (heat treatment), calcined samples analysis by X-ray fluorescence (FRX) and aftermost using as pozzolan. The pozzolans utilization stages was carried out by the partial replacement of Portland Cement by pozzolans addition percentages, in conventional construction concrete mixes. The additions percentages were 10%, 30% and 50%, beyond to producing a concrete mix without any addition in the form of a control dash. Finally, the specimens were obtained for the resistance analysis of these mixtures with additions, by comparing these with the strength results of a conventional concrete mix (without addition), besides to results analysis based on parameters established by NBR 6118:2014. The soil samples analyzed by FRX showed average values of 0.15; 6.91; 20.36 and 70.87% for contents of calcium oxides, iron, aluminum and silicon, respectively. The kaolinite content average value in the analyzed samples was 51.53%. In the consistency test, the cement substitutions for pozzolan presented acceptable values in soil samples from Candeias do Jamari NBR 8953:2015 and less than acceptable in the Ji-Paraná sample having restriction in its use,
however consistency problems can be solved with the use of concrete additives. The mechanical resistance indexes required by NBR 6118:2014 presented gradual increases over time, however only in the 10% Candeias do Jamari and Ji-Paraná replacement reached the minimum resistance of 20Mpa; in Ji-Paraná the up to 30% replacement reached the minimum of 15MPa to be considered a concrete, but without structural purposes.

MEMBROS DA BANCA:
Presidente - 1545801 - JAIRO ANDRE SCHLINDWEIN
Externo ao Programa - 3063165 - DIEGO HENRIQUE DE ALMEIDA
Externo ao Programa - 1548288 - PETRUS LUIZ DE LUNA PEQUENO