Methods for Evaluation of Affinity of Bitumen to Aggregate
Keywords:
phase affinity, bitumen, aggregatesAbstract
The purpose of the study was to compare techniques related to a laboratory method for determination of affinity of bitumen to aggregate. The standard method EN 12697-11/AC was used for the purpose. Three methods can be used: the rolling bottle method, static method and boiling water method. Visual, photographic and extraction evaluation of stripped surface on aggregate after the rolling bottle method was used and compared. The static method showed submarginal differences among modified bitumen. The boiling water method showed the best repeatability in evaluation of stripped surface by acidimetry. The acidimetric determination of the affinity is recommended for the bottle rolling method instead of visual evaluation. Polymer modifiers as additives affecting the affinity were also compared.