O efeito filler em blocos de pavimentação com uso do pó de mármore

Abstract

Civil construction is one of the sectors that represents the greatest potential in the generation of wealth and jobs in the world. However, as a result of its economic relevance, it is one of the most impactful segments to the environment. This is due to the extraction of natural resources and the large generation of solid waste, leading to the need for practices aimed at minimizing waste and sustaining the activity. Therefore, there has been a significant growth in studies on the reuse and recycling of waste materials in recent decades, and one of the options for use of these materials is in the composition of concrete and mortar, as aggregates. An example of waste that has shown this applicability is marble dust which presents more homogeneous characteristics when compared to natural sands, since it is a by-product of an industrial process. In addition, that material shows high compressive strength due to its mostly limestone composition, contributing to an improvement in concrete performance. In this context, the present work aims to verify the effect of marble dust as a filler, analyzing concrete with partial replacement of natural sand in the production of paving blocks. In order to determine the best ratio of replacement, tests were carried out on three concretes, one of which was a reference and two were experimental, with 15% and 25% of replacement of the natural sand mass by marble powder, respectively. In this context, the results showed an improvement in compressive strength, absorption and, consistency for both experimental mixtures, and in the case of absorption content, the improvement was more substantial for the 25% replacement of natural sand. It can be said that this is due to the reduction of air voids, caused by the increase in the filler content from the addition of marble powder to the concrete. Other properties, such as the modulus of elasticity and specific mass, did not vary show any variation in the results with the replacement of the natural aggregate. The microscopic analysis of the mixtures also showed an improvement with the replacement, verified by the reduction of porosity and microcracks. For the tests that involved the average of the results, an analysis of variance (One-Way ANOVA) was performed, in order to validate the results and give greater credibility to the research. Therefore, it is concluded that the experimental concretes met the normative requirements for strength and absorption, indicating their high application potential in the production of concrete blocks for paving.