Tribological characterization of bituminous binders with Warm Mix Asphalt additives

Evaluation of Graphite Nanoplatelets Influence on the Lubrication Properties of Asphalt Binders

“…In tribology, the lubrication properties of a material placed between two solids in relative motion is normally described through the Stribeck curve ( Figure 1), which shows the evolution of the coefficient of friction µ as a function of the sliding speed [16,17]. The change in the coefficient of friction values is due to the variation of the thickness of the lubricating film, as shown in Figure 1.…”

“…The change in the coefficient of friction values is due to the variation of the thickness of the lubricating film, as shown in Figure 1. The Stribeck curve can be generally divided into four regions, which correspond to different regimes of lubrication [16,17]:…”

“…However, in addition to the sliding speed, other important parameters also govern the phenomenon. Since friction is not an intrinsic property of the material but of the overall system, it strongly depends also on the nature, surface roughness and wear of the solids in contact [16,17]. Such factors are extremely crucial mainly when the lubricating film is not thick enough to separate all solid asperities.…”

“…In this regard, a new test method, used for lubricants and based on tribology, has been recently proposed in order to characterize the lubricating behaviour of asphalt binders [15][16][17][18]. To date, this approach has been used mainly to investigate the lubricating properties of warm mix asphalt (WMA) binders, produced with different WMA technologies [17,19,20]. Other fields of application, such as the modification with nanomaterials, should be considered.…”

“…Other fields of application, such as the modification with nanomaterials, should be considered. Although the use of rough substrates in the tests is generally recommended for the study of asphalt binders [10,17], only smooth substrates have been used up to now in previous research.…”