Asphalt quality and strength of asphalt pavements

X-ray fluorescence detection of waste engine oil residue in asphalt and its effect on cracking in service

“…The colloidal sol/gel nature of asphalt cements has been investigated for a very long time with important contributions published at regular intervals (Nellensteyn 1923, Pfeiffer and Van Doormaal 1936, Benson 1937, Pfeiffer and Saal 1939, Saal and Labout 1940, Traxler and Romberg 1952, Traxler 1961, Pechenyi 1977, Lesueur et al 1996. A sol material exhibits behaviour that is largely Newtonian while a gelled material behaves in a non-Newtonian manner with significant elasticity, delayed elasticity and non-linearity in viscoelastic properties Labout 1940, Lesueur 2009).…”

“…A sol material exhibits behaviour that is largely Newtonian while a gelled material behaves in a non-Newtonian manner with significant elasticity, delayed elasticity and non-linearity in viscoelastic properties Labout 1940, Lesueur 2009). The general consensus in the literature is that overly gelled, blown or elastic materials should be avoided for paving applications (Traxler 1961, Pechenyi 1977, Van Gooswilligen et al 1989, Van de Ven and Van Assen 1996, Isacsson and Zeng 1998. Thermal stresses are able to relax in sol-type asphalts but are retained in gel-type asphalts, often leading to premature and excessive cracking.…”

“…viscous behaviour is preferred over elastic behaviour) (Pechenyi 1977, Van de Ven and Van Assen 1996, Isacsson and Zeng 1998.…”

Effect of Waste Engine Oil Residue on Quality and Durability of SHRP Materials Reference Library Binders

“…It is generally accepted that gelled materials should be avoided, because of their tendency for thermal cracking (19,(31)(32)(33)(34)(35)(36)(37). Cold temperature stresses are able to relax in sol-type asphalts but are retained in gel-type materials.…”

“…Adding WEO to asphalts with modest to high asphaltene contents results in effects analogous to regular aging (loss in phase angle and increase in stiffness). Those binders that retain a high phase angle at both low and high temperatures are known to do well in terms of resisting thermal and fatigue cracking (19,(31)(32)(33)(34)(35)(36)(37)(38)(39)(40). However, the absolute phase angle after aging is likely more important than the loss.…”