Birziklatutako poliuretano-aparraren erabilera nahaste bituminosoetan: Employment of recycled polyurethane foam in bituminous mixes

Abstract

Many substances have been used to modify bitumens with the aim of enhacing their properties and performance, but the most widely used are the polymers. Polyurethane foam is a waste product from themal insulation, which is frequently deposited in landfills. Waste polyurethane foam was selected as a possible bitumen modifier in bitumens to produce two differente bituminous mixes: hot mix asphalts with a B 50/70 bitumen and mastic asphalt with B 35/50 bitumen. Different quantities of polymer were added to the bitumens, from 1 % to 5 % in weight of the bitumen. In both bitumens it was shown that 5% or more of polymer made samples became rough and with low workability and, hence, they were discarded. Specimens of both bituminous materials were produced with 4% of polymer. The Marshall test showed that modified hot mix asphalt obtained improvements in stability and a lower deformation when compared to non-modified mixtures. Similarly, the modifed mastic asphalts showed lower identation values than non-modified samples, being able to be employed in road with heavy traffic. Consequently, the waste polyurethane foam resulted in a promising bitumen modifier that enhances bitumen properties.