Vibration-induced aggregate segregation in asphalt mixtures

Abstract

Aggregate segregation in asphalt mixture is a bothersome engineering issue during pavement construction. The practitioners have some measures to mitigate the segregation potential based on experiences which, however, can only reduce the risk to a certain extent. In this research, the authors aim to contribute to the discussion in a rational non-empirical way, by using novel experimental and numerical techniques. A case study is carried out to investigate the vibration-induced segregation in asphalt mixtures, corresponding to the circumstance arising during material transportation to the construction site. A novel experimental test is conducted for evaluating the segregation characteristics of asphalt mixtures under vertical vibration in laboratory conditions. A numerical investigation based on discrete element method is further performed to study the phenomenon from a micromechanical point of view. The obtained experimental and numerical results indicate that vibratory loading induces aggregate size segregation in asphalt mixtures, and the degree of segregation is influenced profoundly by the adhesive properties of bituminous binders and the aggregate gradation.

Quest for improving service life of asphalt roads

“…Based on the results with the quasi-static slump test, another novel test was created and combined with DEM for inquiring vibration-induced segregation as found on bumping trucks on their way from the asphalt plant to the construction site. First results demonstrate that the largest particles show greatest tendency to segregate, tending to rise up on top of the smaller ones, and that the segregation potential appears to increase with continuous vibration in a nonlinearly proportional way to vibration time [26].…”

“…This paper gives examples of selected efforts and research initiatives in that direction during the last decades based on own experience and involvement in projects within the road engineering/sealing components lab at Swiss Federal Laboratories for Material Science and Technology (Empa) [3,[8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]27] and both the highway/railways engineering and building materials group at Swedish Royal Institute of Technology (KTH) [24][25][26][27][28]. Some of these activities are closely linked to the work within different international technical committees of the International Union of Laboratories and Experts in Construction Materials, Systems and Structures (Rilem), e.g.…”