Banca de QUALIFICAÇÃO: LORENA KARLA SOARES PEIXOTO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : LORENA KARLA SOARES PEIXOTO
DATE: 23/03/2023
TIME: 09:30
LOCAL: https://meet.google.com/nvr-ifux-gdu
TITLE:

Evaluation of durability parameters against attack by chloride ions in self-compacting concrete using recycled aggregates from civil construction waste

KEY WORDS:

Self-compacting concrete. CDW. Recycled aggregates. Metakaolin. Attack by chloride ions. Durability properties.

PAGES: 26
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Construção Civil
SPECIALTY: Materiais e Componentes de Construção
SUMMARY:

As economic development drives the accelerated pace of construction, it is known that it projects a global environmental crisis as a result of the waste of natural resources from non-renewable sources, thus arousing the search for alternatives for reuse of construction and demolition waste (CDW). In this study, the influence of incorporating recycled aggregates of CDW, sand and gravel, on the durability parameters in mixtures of self-compacting concrete (SCC), with and without the addition of metakaolin, submitted to two exposure conditions: in open air and in chloride ion attack cycles, was verified. Five mixtures were produced: (1) reference SCC, with natural sand and gravel; (2) SCC with recycled sand and gravel; (3) SCC with recycled sand and gravel and addition of 10% MK; (4) SCC with recycled sand, natural gravel and addition of 10% MK and (5) SCC with natural sand, recycled gravel and addition of 10% MK. The water/cementitious material ratio was kept constant for all mixtures and the additive dosage was adjusted according to the variation in the use of aggregates. The evaluation of mechanical properties and durability was performed from tests of axial compressive strength, ultrasonic pulse velocity, chloride penetration, chloride ion diffusion, electrical resistivity and corrosion potential. The results showed that the SCC properties were reduced with the use of recycled CDW aggregates. However, for some durability indicators, SCC with recycled aggregate behaved similarly to SCC with natural aggregates. The addition of metakaolin compensated for the decrease in quality of the SCC with the use of recycled aggregates. The SCC mixture with recycled sand and metakaolin stood out positively in relation to the others, with better results than the reference mixture.

COMMITTEE MEMBERS:
Interno - ***.621.844-** - MARCOS ALYSSANDRO SOARES DOS ANJOS - IFRN
Interna - 1507841 - MARIA DAS VITORIAS VIEIRA ALMEIDA DE SA
Externa ao Programa - 1717461 - LUCIANA DE FIGUEIREDO LOPES LUCENA - UFRN