Evaluation of Different Test Methods for Bitumen Adhesion Properties

The adhesion between mineral aggregates and bitumen is an important criterion which describes the quality of the asphalt mixture, asphalt pavement performance and resistance to distress. The lack of bonding can lead to a significant asphalt pavement damage. For the evaluation of the adhesion behavior between bitumen and aggregates, used in road construction, many test methods are known. Therefore, it is important to assess the most appropriate test method for bitumen adhesion properties. In the European standard three testing methods are used to determine the affinity between bitumen and aggregate: Rolling-Bottle-Test, static water storage, detachment in boiling water. Whereas, in the Lithuanian standard – boiling water test method is used. The aim of this research is to determine an effective test method for bitumen and aggregates adhesion properties. Also, to investigate the validity of the test methods for the Lithuanian asphalt binders and to compare the adhesion test methods and parameters used in European standard. The materials used in the experiment research: 5 types of aggregates (granite, dolomite, crushed gravel, and quartz diorite), 6 types of asphalt binders used in Lithuania market (50/70, 70/100, and PMB 45/80-55) and 2 additives – Iterlene 400/IL, Antrocelbond. The test results showed a difference in bitumen adhesion according to test methods used in European and Lithuanian standards, since these methods differ in their methodology, preparation of the samples and results of the measurement unit. Based on the results of this research the conclusions and recommendations were made for determination of bitumen and aggregates adhesion in Lithuania.