Produção de blocos intervalados de concreto com a substituição parcial do agregado miúdo natural pelo agregado miúdo reciclado de corpos de prova de concreto

Abstract

With the automotive revolution, highways became the main means of transportation, leading to a growing demand for construction materials. However, civil construction and the consumption of natural resources generate waste that affects the environment. To help solve this problem, the recycling of construction and demolition waste is proposed in the construction of interlocking pavement, through the recycling of aggregates. The research aims to develop an alternative sustainable concrete block for interlocking pavement, using Recycled Concrete Fine Aggregate (RCFA) in different proportions: 0%, 5%, 10%, and 15%. 80 concrete blocks were produced, divided into reference mixes (BCR) and with RCFA (BCRE5%, BCRE10%, and BCRE15%), subjected to water absorption, dimensional evaluation, and compressive strength tests. A statistical study was also conducted to determine if the percentages of RCFA altered the properties of the produced concrete. At the end of the research, it was possible to observe a decrease in the slump test of the concrete mixes produced with different percentages of RCFA compared to the reference block, a decrease in water absorption compared to the reference block. In the dimensional evaluation, the four types of concrete blocks presented maximum and minimum values within the limits imposed by the Standard for the three dimensions. In the compressive strength test, no concrete block reached the minimum value required by the Standard. Finally, in the study conducted, it was noticed that the concrete blocks did not reach satisfactory levels in the water absorption and compressive strength tests, according to NBR 9781 (ABNT, 2013). However, the use of RCFA can be a sustainable and viable alternative for the production of concrete blocks for interlocking pavement, provided that adjustments are made to the mix to guarantee the quality of the block.