Uniformity and mechanical properties of dense asphalt concrete with steel wool fibers

• Fibers in asphalt concrete are known for enhancing its strength and fatigue characteristics while increasing ductility. Additionally, fibers may increase the dynamic modulus, moisture resistance, creep compliance, rutting and freeze-thaw resistance of asphalt concrete, preventing the formation and propagation of cracks. The addition of fibers may influence the properties of the material, but it is not clear how is this influence, and which are the optimum amount, length and diameter of fibers needed for not having a negative impact on the mixture. For this reason, fibers (steel wool) distribution and their effect on the porosity and electrical conductivity of dense asphalt concrete have been studied. With that purpose, 25 different mixtures, with the same aggregates gradation and amount of bitumen, but with two different lengths of fibers, four different percentages, and four different diameters of steel wool have been built. Results show that long and thin fibers produce many clusters and a poor distribution, while short and thick fibers disperse very well in the mixture. It was also observed that fibers can be seriously damaged during the mixing and compaction processes. Finally, it has been found that steel wool fibers do not have a relevant influence on the particle loss resistance and flexural strength of dense asphalt concrete.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Samhällsbyggnadsteknik -- Infrastrukturteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Civil Engineering -- Infrastructure Engineering (hsv//eng)

Nyckelord

Asphalt mixture

Clusters

Fibers distribution

Mechanical properties

Porosity

Steel fibers

Compaction process

Creep compliance

Electrical conductivity

Fatigue characteristics

Freeze-thaw resistance

Moisture resistance

Propagation of cracks

Asphalt concrete

Asphalt mixtures

Concretes

Creep resistance

Electric conductivity

Mixtures

Wool

Wool fibers

Yarn

Asphalt

Compaction

Concrete

Creep

Resistivity

Steel

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)