Abstract Atomic force microscopy (AFM) has the capacity to distinguish among different phases at high resolution, and it is widely used in obtaining topography and mechanical property maps for asphalt binders. This study investigated the effects of long-term aging on both SBS-modified asphalt and base asphalt using AFM. In describing the study findings, this paper introduces two new indices used to quantify changes in the microstructures of asphalt, namely, the percentage of elliptical bee structures and surface roughness. In addition, the Derjaguin-Muller-Toporov modulus and adhesive force were measured to quantify the mechanical properties of the micro-phases. Finally, to evaluate the influence of aging on composite phase properties, a parallel model from the field of composite materials was introduced and applied. The results indicate that aging significantly affected the microstructures and mechanical behavior of micro-phases of asphalt binders. Aging also had a significant influence on the microstructures of the asphalt, especially in the bee structures. The percentage of bee structures increased or decreased after aging depending on the asphalt binder type, while surface roughness always decreased. Aging also increased the composite modulus of the micro-phases and decreased the composite adhesion of the micro-phases. These findings are in agreement with the macroscale aging behavior of asphalt binders.

Investigation of Microscale Aging Behavior of Asphalt Binder Using Atomic Force Microscopy

Ultraviolet ageing of bituminous materials: A comprehensive literature review from 2011 to 2022

In this paper, the effect of physical hardening and aging temperatures on the low temperature rheological properties of the asphalt binder is experimentally investigated and modelled. First, Dynami...

Investigation on the effect of physical hardening and aging temperature on low-temperature rheological properties of asphalt binder

Application of atomic force microscopy in bitumen materials at the nanoscale: A review

Application of Atomic Force (AFM), Environmental Scanning Electron (ESEM) and Confocal Laser Scanning Microscopy (CLSM) in bitumen: A review of the ageing effect.

Asphalt binder ageing leads to significant changes in mechanical and physicochemical properties and often to premature cracking in asphalt pavements. A polymer-modified asphalt binder is repeatedly...

https://www.tandfonline.com/doi/pdf/10.1080/14680629.2020.1820891

Rheological, spectroscopic and microscopic assessment of asphalt binder ageing

Laboratory and field ageing of SBS modified bitumen: Chemical properties and microstructural characterization

In this study, usual asphalt mixtures are tested using known and established performance testing methods. In a second step, the asphalt mastics (mastic considered as composite of asphalt binder and aggregate filler) that correspond to the asphalt mixtures are investigated with regard to their rheological properties. All asphalt mixtures and corresponding asphalt mastics are subjected to (i) creep tests in the high temperature range, (ii) fatigue tests in the intermediate temperature range, and (iii) relaxation tests in the low temperature range. Hence, test results are obtained on both scales, the asphalt mixture scale and the corresponding asphalt mastic scale. At the mastic scale, a new set of rheological tests is composed. This set covers the full temperature range, but all results are obtained from the same Dynamic Shear Rheometer (DSR). In the last step, data from both scales are correlated, and finally, sound regressions are identified between asphalt mixture performance parameters and asphalt mastic rheological parameters. It is concluded, that the identified set of rheological tests at the asphalt mastic scale provides a rapid and significant estimate of asphalt mixture performance.

Relating Asphalt Mixture Performance to Asphalt Mastic Rheology

The 4 mm parallel plate geometry in the DSR with a new sample installation method is proposed to evaluate low temperature rheological properties of asphalt binders. For this purpose, the influences of temperature conditioning and normal force were studied, and finally suitable test conditions were identified to run T-f-Sweep tests in oscillation mode. Appropriate shear stresses were identified by amplitude sweep tests considering the instrument limitations. Consequently, testing conditions and instrument limitations are determined, which need to be respected to obtain precise and repeatable rheological data.

On low temperature binder testing using DSR 4 mm geometry

Asphalt mastic is known to play an important role when determining the fatigue performance of asphalt mixture. Time sweep test using a Dynamic Shear Rheometer can be used. However, a long testing t...

Johannes Büchner

Papers

Rheological, spectroscopic and microscopic assessment of asphalt binder ageing

Laboratory and field ageing of SBS modified bitumen: Chemical properties and microstructural characterization

Relating Asphalt Mixture Performance to Asphalt Mastic Rheology

On low temperature binder testing using DSR 4 mm geometry

Accelerated Dynamic Shear Rheometer Fatigue Test for investigating asphalt mastic