Asphalt, or bitumen, is a petroleum product used in the road (pavement), roofing and construction industries. A mixture of aromatic hydrocarbons (varying with geographical source), this black viscoelastic material is considered to be a complex colloidal system including inorganic elements such as S, Ni and V.
Asphalt is used as a binder with aggregates in road (pavement) construction and as such determines performance and lifetime. Additives such as polymers, crumb rubber, oils, REOB (Re-refined Engine Oil Bottoms) and pH adjusters are used to enhance mechanical properties in modified asphalt binders. Asphalt emulsions are also used as water-proofing and re-surfacing materials.
With our asphalt industry and application knowledge, Malvern Panalytical systems enable:
• Grade testing to industry standards such as AASHTO , ASTM and EN specifications
• Formulation development, additive optimization and quality control metrics
• Accurate measurement of absolute molecular weight, molecular size, Molecular Weight Distribution (MWD), intrinsic viscosity, branching, and other intrinsic properties
• Determination of Mixing and Compaction Temperatures
• Improvement and insight to enhancing pavement preservation practices
• Blend testing of Warm Mix, Crumb Rubber/Ground Tire Rubber (GTR) and Recycled Asphalt Paving (RAP)
• Solids/Torsion testing of Asphalt Cores for Fatigue or Accumulated Strain testing
• Emulsion stability, particle sizing and viscosity profiling of Asphalt Emulsions
• Elemental analysis and screening for the presence of re-refined engine oil bottom (REOB) in asphalt binder
• Benchmarking and comparison of competitive products.
• Full asphalt characterization of rheological behavior with Mastercurves
• Penetration, pull off and tack testing
Rheological characterization by Dynamic Shear Rheometers (DSR) is the standard method of classifying asphalt binders for behavior over time and loading conditions, and in different climates.
While some still use viscosity (vis) & penetration (pen) methods for grading, the use of DSR grading methods provides a much broader range of information about the asphalt performance properties and its suitability for desired applications. This is especially the case with engineered binders; binders designed with elastomeric properties to reduce rutting, aging, thermal & fatigue cracking.
Blending recycled materials (e.g. REOB, RAP, and GTR) in asphalt could give enhanced properties and reduce cost while being environmentally conscious. Used automobile oil can be re-refined to recycle its hydrocarbons. The asphalt-like residue from recycling engine oil, known as Re-refined Engine Oil Bottom (REOB) contains a concentration of the inorganic elements used in manufacturing engine oil lubricants, including Ca, P, and Zn and sometimes Mo and Ba. Other elements derived from burning fuel and engine wear may also be found in REOB such as Fe, Cl, S, Si and Cu as well as others. REOB is primarily used to soften the asphalt binder, but may also cause premature failure and is banned in some areas. Consequently, it is necessary to be able to detect the presence of REOB, and X-Ray Fluorescence (XRF) is commonly used for this purpose.