The influence of post-consumer car mats waste on selected concrete parameters

Czestochowa University of Technology, Faculty of Civil Engineering

^* Corresponding author: apietrzak@bud.pcz.czest.pl

Abstract

In recent years, a systematic increase of various types of wastes has been observed, including polymeric wastes that, to a large degree, are difficult to manage. The present paper deals with the problem of car mats wastes and the possibility of their application for producing concrete composites. The scope of the research involved designing and making concrete mixtures modified by waste rubber retrieved from rubber car mats. For the experiment the authors used: Portland cement CEM I 42,5R, sand, gravel aggregate of the 2-8 and 8-16 fractions, water, plasticizing and aerating admixture and car mats wastes fragmented into 0-2 mm and 2-8 mm. The authors made 4 series of concrete samples modified by wastes, for which the following factors have been assigned: compression strength after 7 and 28 days of maturing, absorptivity, frost resistance F100 of freezing and thawing and bulk density. In two samples’ composition (S1 and S2) the authors used 2-8 mm fraction rubber wastes as a substitute for 2-8 mm gravel in the amount of 5% and 7,5% of the cement bulk, making the density correction of 2-8 gravel. In contrast, in the remaining two samples S3 and S4 were modified by rubber wastes of the 0-8 mm fraction in the amount of 5% and 10%, respectively, of the cement bulk, subtracting a certain amount of the aggravate mixture at the same time. The research conducted for the series of the designed concrete samples, unfortunately did not confirm the thesis that rubber wastes retried from rubber car mats could be reused as the aggravate substitute.