Avaliação da substituição da areia natural por areia de britagem nas propriedades do concreto de cimento portland

Abstract

This work aims to evaluate the influence of replacing natural sand with crushed sand on the fresh and hardened properties of a conventional concrete, with the aim of contributing to the mitigation of the exploitation of natural sand and disposal of accumulated stone dust. in the quarries in the form of crushing sand. Five treatments were defined, differing only in the proportion of fine aggregates, with other fixed parameters, namely the contents tested were 0% (reference trait), 25%, 50%, 75% and 100% of crushed sand in relation to the natural sand. For analysis in the fresh state, the slump test of the truncated cone was carried out, resulting that the higher the crushing sand content used, the lower the slump obtained, due to the greater specific surface of the pulverulent material. For the analysis in the hardened state, a compression test, traction by diametral compression and modulus of elasticity were performed. Regarding compression, it resulted in greater resistance in all mixes with some amount of crushed sand, with emphasis on the mix with 25% of crushed sand and 75% of natural sand, in which it obtained the best results. It was observed that substitutions between 25% and 50% are more viable because they improve the mechanical capacity of the material without large slump losses, which in turn can be adjusted to match the slump of the reference mix, obtaining a better cost-benefit ratio.