Characterisation and modelling of vapour-conditioned asphalt binders using nanoindentation

Abstract

Nanoindentation tests were conducted on unconditioned and vapour-conditioned asphalt binder samples to determine damage processes by characterising contact creep data and using viscoelastic mechanical models. For vapour-conditioned asphalt binders, a thin film of asphalt binder was prepared on a glass slide and subjected to relative humidity (RH) of 25%, 49% and 71% inside enclosed desiccators using three aqueous solutions: potassium acetate, potassium carbonate and sodium chloride, respectively. Based on the nanoindentation contact creep test data, it was observed that vapour-conditioned asphalt binders showed larger indentation viscous depth than the unconditioned binders. Indentation test data were modelled using viscoelastic mechanical models such as Burgers and Maxwell models. The models showed that elasticity increased and viscosity decreased in the vapour-conditioned asphalt binders. In 71% RH-conditioned binders, elastic components of Burgers model, E 1 and E 2 increased about 10% and 15%, respectively, compared to the unconditioned binder. The relaxation time decreased about 35% and retardation time increased about 69% in 71% RH-conditioned binders compared to unconditioned binders.

Microstructural Characteristics of Interfacial Zone in Asphalt Mixture Considering the Influence of Aggregates Properties

“…To determine the viscoelastic parameters based on the indent penetration, linear spring and dashpot elements are used to represent the creep behavior of a wide range of materials according to the hold period force-displacement data of nanoindentation test. Then, mechanical characteristics are described using viscoelastic mechanical models such as the Burgers and Maxwell models [28,29]. Besides, relation time and creep compliance are used to provide quantitative indicators to evaluate viscoelastic material properties [30,31].…”

Examination of Poly (Styrene-Butadiene-Styrene)-Modified Asphalt Performance in Bonding Modified Aggregates Using Parallel Plates Method

“…The corresponding methodologies can be divided into three major categorizations that are dependent on physical scales: micro-scale [3], meso-scale [4], and macro-scale [5]. Numerical simulations and analytical approaches are commonly applied at these scales, such as molecular dynamics (MD) [6], finite element method (FEM) [7], and discrete element method (DEM) [8]. A fact was known, as that asphalt-aggregate bonding illustrates an important impact on the performance of HMA.…”

Creep and Fatigue Performance of Partial Vapor Conditioned Asphalt Binder

“…Moisture-induced damage in Asphalt Concrete (AC) has been studied for many years by conventional and sophisticated laboratory tests, and by using advanced numerical methods [1][2][3][4][5][6][7][8]. Recently, researchers have shown interest on vapor-induced damage in AC since micro-and macro-scale laboratory tests can be performed on vapor conditioned test samples [8][9][10][11][12]. Moisture diffuses through the AC in both liquid and vapor form [8,13].…”

“…Later, fatigue test was done on AC samples at 100% and 0% Relative Humidity (RH) [14]. Following the footsteps, asphalt binder samples were partially vapor conditioned, and nanoindentation test was done to access the vapor-induced damage by developing a mechanical model of the asphalt binder [10,11]. One viscoelastic (i.e., Bargers model) and one viscoelasticplastic (i.e., Spring-Dashpot-Rigid or SDR model) mechanical models were developed based on the creep nanoindentation tests.…”