Avaliação de resistência à compressão de concreto com teores de resíduos das atividades extrativistas de macaúba, coco babaçu e jatobá no cariri cearense.

Abstract

Concrete is widely used in civil construction, consisting of cement, water, and aggregates such as sand and gravel, and may also incorporate additives and/or admixtures that improve its workability and strength. However, its production is associated with the high consumption of non-renewable natural resources and the significant generation of waste, making it an activity with a significant environmental impact. In this context, the search for more sustainable solutions that minimize these effects is intensifying. Among these alternatives, the use of alternative concrete stands out, obtained from the partial replacement of conventional aggregates with plant-based waste from extractive activities. Considering this scenario, the present study aims to evaluate the performance of alternative concrete using waste from macauba, babassu coconut, and jatobá. The alternative concretes analyzed were produced with partial replacement of fine aggregates, with the bioaggregates previously characterized in terms of their physical properties and incorporated in proportions of 10% and 30%. Furthermore, a conventional reference concrete mix was developed, used as a basis for comparing the final strength and for defining the mix design of the alternative concrete mixes developed. Axial compression strength tests were performed at 7 and 28 days. In the slump tests, with the exception of the mixture containing 10% macauba, high values were obtained, ranging from 160 mm to 225 mm. The compression strength results indicated that the partial replacement of conventional aggregates with vegetable residues caused a reduction in final strength, this influence being dependent on the type and content of bioaggregate used. Statistical analysis revealed that macauba showed the most promising performance among the materials studied, with the mix containing 10% replacement reaching a compressive strength of 14.83 MPa, the best result among the alternative concrete mixes. In contrast, jatobá showed the lowest strength values, possibly due to its high water absorption rate.