Survey for Reactive Blends of Asphalt and Antistripping Additives

摘要

When subjected to elevated temperatures, some blends of asphalts and antistripping additives undergo a reaction that causes the additive to be ineffective. The frequency of occurrence of reactive asphalt-additive blends used by the Virginia Department of Highways and Transportation was determined to ascertain the level of testing that is necessary to prevent acceptance of their use in asphaltic paving mixtures. Samples of asphalt cement were collected, combined with the two additives used most frequently by the Department, heat treated, and tested. Bottle and stripping tests were used to evaluate the reactivity of the blends. Although approximately 50% of the asphalts reacted with an additive, the reactions were not detrimental when normal additive doses were used. It was concluded that no modifications to the present test procedures and frequency of tests are needed.