Banca de DEFESA: INGRID SILVA ASSIS SANTANA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : INGRID SILVA ASSIS SANTANA
DATE: 07/08/2023
TIME: 09:00
LOCAL: Ambiente virtual
TITLE:

Sisal fibers reinforced cement breeze blocks: geometric Project, prototyping and mixture design

KEY WORDS:

Breeze blocks, 3D print, composites, sisal fibers, pozzolan, mixture design.

PAGES: 120
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Construção Civil
SPECIALTY: Materiais e Componentes de Construção
SUMMARY:

The application of breeze blocks is notable for their significant climatic potential, as they can reduce energy consumption in buildings. Currently, progress has been made in developing unconventional geometries and exploring materiality studies to enhance the functionality of these elements. In this context, this study proposes the development of geometric designs for breeze blocks using the Rhino7/Grasshopper software. Parameters such as dimensions, opening orientations, and fitting systems of the parts are applied, along with prototyping through additive manufacturing, to create molds. This approach combines fiber-reinforced cementitious composites to reproduce hollow elements on a laboratory scale. Investigations were conducted to study the consumption of calcium hydroxide (Ca(OH)2) in the cementitious matrix using response surface design. The aim was to optimize the curing process to ensure the viability and durability of the fibers incorporated into the matrix. This step determined the ideal curing parameters, considering a proportional relationship between high curing temperatures and a pozzolanic content of 30% to consume calcium hydroxide equal to 0%. To make the practical application of composites feasible, rheological and mechanical properties were studied using Portland Cement CP V ARI, pozzolans, sisal fibers, superplasticizer additives, and viscosity modifiers. Statistical mixture design and simultaneous optimization techniques were applied to develop formulations. Consequently, the ideal self-compacting formulation was determined, considering the influence of inserting 3% sisal fibers with a length of 30mm. This formulation achieved a spreading diameter of 200mm and mechanical properties compatible with sealing materials. The next step involved producing the hollow element and assessing the feasibility of the designed geometry by creating a mold using silicone material. The optimized formulation led to the development of the breeze block on a laboratory scale, resulting in a mixture that facilitated self-densification in the mold and ensured uniform disposition of the sisal fibers, thereby improving the distribution of forces. The bending test results demonstrated that the cast elements achieved excellent toughness and fracture energy. Furthermore, the parts produced using unconventional geometries exhibited compressive strength compatibility with hollow blocks without structural function, according to NBR 6236 (2016), with a strength of 12.77 MPa. The breeze blocks designed through additive manufacturing and using self-compacting cementitious matrices reinforced with sisal fibers offer opportunities for advancing the geometries of breeze blocks. They have the potential to expand applications in architecture and civil construction.

COMMITTEE MEMBERS:
Interno - ***.925.915-** - PAULO ROBERTO LOPES LIMA - UEFS
Externa ao Programa - 2358674 - ERICA DE SOUSA CHECCUCCI - UFBAExterna à Instituição - LEILA APARECIDA DE CASTRO MOTTA