The Use of Asphalt Rubber in a Motorway Section Pavement Rehabilitation in Portugal



Taking advantages of its several benefits, there has been a growing use of asphalt rubber in the bituminous mixes for the pavement wearing course. Asphalt rubber in the surfacing course, among other advantages, can strongly contribute to cope with the reflective cracking and to mitigate the road noise, in maintenance and rehabilitation works.
An open graded asphalt rubber was used in the rehabilitation works of a highly trafficked motorway section (M5), with over 120 000 vehicles per day, for the surfacing course. The motorway section, built in Portugal in the early 40’s, was the first one with portland cement concrete slab pavement, with a 2×2 cross section. In the early 90’s, the existing pavement was widened to 2×3 and to 2×4, again with portland cement concrete slab pavement, overlaid
in the entire cross section with bituminous mixes. During the last years, extensive reflective cracking was observed on the pavement surface. The paper describes the existing previous pavement distresses, the technical solutions and the results, emphasizing the contribution of asphalt rubber to overcome the reflective cracking and to mitigate the road noise.

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