Caracterização mecânica e retração em argamassas produzidas com cimento reciclado

José Bernardo Mota Pinho Bandeira

Key information

Authors:

José Bernardo Mota Pinho Bandeira (José Bernardo Mota Pinho Bandeira)

Supervisors:

José Alexandre De Brito Aleixo Bogas (José Alexandre De Brito Aleixo Bogas); Manuel Francisco Costa Pereira (Manuel Francisco Costa Pereira)

Published in

09/29/2020

Abstract

Due to growing environmental concerns, the various countries and international institutions have invested in the search for sustainability. In this sense, concrete being the most used material in construction, is one of the main sources of environmental impact, with cement, in particular, being responsible for more than 80% of the Greenhouse Gases (GHG) released in the production of this material. The present work intends to contribute to the increase of knowledge in the development, production and characterization of thermally activated Recycled Cements (RC). For this purpose, a work with a strong experimental component was developed with the main objective of analyzing the shrinkage of mortars produced with partial or total substitution of Ordinary Portland Cement (OPC) for RC, and also the analysis of its synergetic effect in the presence of different levels of Fly Ash (FA). The work considers residues from pastes of different compactness and also residues from concrete, simulating the most usual real case. The mortars are also subject to mechanical characterization and analysis of the microstructure through capillary absorption tests. With this work it was possible to confirm the potentiality of thermoactivated recycled cement as an addition in mortars, verifying that for identical relation to/l, it is possible to obtain mortars with similar behavior to OPC, but associated to a significant reduction of GHG emissions. It is confirmed the synergetic effect between RC and fly ash, as well as the higher activity and efficiency of RC compared to FA as OPC addition material.