Waste Rubber from End-of-Life Tires in ‘Lean’ Asphalt Mixtures—A Laboratory and Field Investigation in the Arid Climate Region

Waste rubber from end-of-life tires has been proved to be an excellent source of polymeric material for paving applications. Over the years, however, the rubberized asphalt technology has never been used in ‘lean’ (low bitumen content) asphalt mixtures typically used in arid regions. This study offe...

Full description

Saved in:
Bibliographic Details
Main Authors: Stefano Marini, Michele Lanotte
Format: article
Language:EN
Published: MDPI AG 2021
Subjects:
IRI
Online Access:https://doaj.org/article/dd08e9db46be4e76a4137475f8caa47f
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Waste rubber from end-of-life tires has been proved to be an excellent source of polymeric material for paving applications. Over the years, however, the rubberized asphalt technology has never been used in ‘lean’ (low bitumen content) asphalt mixtures typically used in arid regions. This study offers an insight on the potential benefits and drawbacks resulting from this technology if applied in such ‘lean’ mixes. Results show that the ‘lean’ nature of those asphalt mixes eliminates the potential benefits given by the modified bitumen for rutting performance. Instead, the aggregates gradation plays a major role in the response of the materials, with gap-graded mixtures often outperforming those with a dense-graded gradation. On the contrary, fatigue cracking resistance is affected by the bitumen properties, and rubberized asphalt perform better than others. The performance-based analysis suggests that the current specifications tend to overachieve the goal of reducing permanent deformation while cracking becomes a major concern which can be solved by using rubberized asphalt. In the field, gap-graded asphalt with rubberized bitumen showed the best response in terms of skid resistance and noise reduction.