Performance of cementitious composites using modified waste tire rubber as recycled aggregate

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Data

2023-09-18

Tipo de documento

Dissertação

Título da Revista

ISSN da Revista

Título de Volume

Área do conhecimento

Engenharias

Modalidade de acesso

Acesso aberto

Editora

Autores

Rodrigues André, Fellipe

Orientador

Aboelkheir, Mostafa Galal

Coorientador

Resumo

The tire rubber, although widely consumed in the automotive industry, creates a challenge to sustainable development due to its non-degradable nature and recycling difficulty attributed to vulcanization. In this regard, the academic world seeks viable alternatives for reutilizing elastomers through various treatments. For over 25 years, the exploration of this polymer as an aggregate in cementitious composites has been a subject of research. However, the reduction of the mechanical properties arises from the weak interface between cement paste and rubber, due to the hydrophobic nature of the polymer, increased by the vulcanization process. This work aims to prepare mortar floor boards by volumetrically replacing fine aggregate with untreated and chemically treated ground tire rubber (GTR). A Vinyl Acetate emulsion was also tested as an admixture additive. At first, two treatment reagents were tested: hydrogen peroxide and potassium permanganate during three intervals of time; 1h, 2h, and 3h. Consequently, the GTR samples were characterized by contact angle, crosslinking degree, and Fourier-transform infrared spectroscopy (FTIR), highlighting the potassium permanganate for 3 hours as the optimal treatment. Prismatic specimens were cast for water absorption, voids ratio, and bulk density tests, alongside mechanical tests for compressive and flexural strength, and dynamic modulus of elasticity. The monitoring of the thermal behavior of the rubberized floor boards was through the use of thermocouples during the exposure to solar radiation in an open environment. The volumetric replacement of 10% of fine aggregate by the treated GTR showed that the results did not undergo a significant change closest to control samples for all conducted tests. The treated GTR caused 21% increase in compressive strength and 27% in flexural strength. The disposal of waste tires for use as recycled aggregate in cementitious composites reduces the inappropriate disposal of the product, contributing to sustainable development in its 3 pillars, environmental, social and economic, and also contributes to the Sustainable Development Goals (SDG) 3, 6, 11, 12, 13 and 15 of the 2030 Agenda.

Palavras-chave

rubberized mortar, recycled aggregate, end of life tire, chemical treatment, agenda 2030, sustainability

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