Recently, the Human Bitumen Study has been finished (Schlüter, 2011). Including 500 workers from more than 80 construction sites it represents the world-wide largest study on adverse health effects caused by bitumen. The study answers a question that has been controversially discussed since decades: Bitumen exposed workers do not show higher levels of DNA damage than unexposed individuals. On t...

One of the important factors of cracks on the asphalt pavements is bitumen aging that associated with the loss of volatile components and oxidation of asphalt binder. This paper is about effect of Styrene-Butadiene-Styrene (SBS) polymer on asphalt aging In order to decrease asphalt aging effects. For this purpose samples of base bitumen and SBS modified bitumen aged according to the rolling thi...

Layered double hydroxides (LDHs) are an ultraviolet-light (UV) resistant material. In this study, LDHs were used to modify bitumen. The optical and UV aging properties of LDHs modified bitumen were investigated. Firstly, the thin films of bitumen, with and without LDHs, were prepared. By using the UV-Vis spectrophotometer, absorbance, reflectance, and transmittance of bituminous thin film were ...

Atomic force microscopy (AFM) is capable to picture the topology of bitumen at a submicrometer level and optical spectroscopy can gather chemical information [1-3]. Here we combine AFM and Raman spectroscopy, which allows a better specification of the chemical origin of bitumen. AFM imaging was performed from the topology, following with Raman imaging from the same area correlating the chemical...

the neat bitumen, an oil refining by-product, has its own inherent weakness under long-time loading at low and high temperatures. these performance limitations of neat bitumen have led researchers to modify its physical andmechanical properties. according to several studies, polymers can be used to modify the properties of bitumen. due to much lower production costs and aiming to reduce environ...

This doctoral thesis consists of a literature review, presented in two papers, and another six papers describing experimental studies of the influence of different kinds of wax and polyphosporic acid on bitumen and asphalt concrete mixture properties. The literature review should give an extensive description of the field of knowledge concerning wax in bitumen. Effects of wax in crude oil, bitu...

Fundamental understanding of micro-mechanical behaviors in bitumen, including phase separation, micro-friction, micro-abrasion, etc., can help the pavement engineers better understand the bitumen mechanical performances at macroscale. Recent researches show that the microstructure evolution in bitumen will directly affect its surface structure and micro-mechanical performance. In this study, th...