Studying the effect of emulsified asphalt type on cold emulsified asphalt mixtures properties

Abstract

Recently, due to environmental restrictions and economics, cold emulsified asphalt mixtures have become the dominant binder material used in cold mix applications. Cold emulsified asphalt mixtures are generally mixtures made using different types of emulsified asphalt with a range of aggregate materials. This research aims to test the physical properties of two types of emulsified asphalt binder (cationic and anionic) used as binders for paving mixtures to evaluate the properties of the resulting cold emulsified asphalt mixtures, using one type of quartz aggregate with different variables such as mixing procedures and compaction effort (75 or 150 blows). The evaluation includes the volumetric and mechanical properties of emulsified asphalt mixture such as bulk density, air voids, and Marshall properties, and compares these with the common local specifications. The results show that the quartz aggregate is more suitable for the cationic emulsified asphalt mixture, due to its negative charge and chemical composition which produce a good bond with a positive charge for cationic emulsified asphalt. However, the results obtained from a test of Marshall stability suggest maximum Marshall stability ratings for mixtures of cationic emulsified asphalt were greater than those for mixes with anionic emulsified asphalt mixtures. The stability values were 16.8 and 10.87, kN respectively, and the optimum emulsified content was 6.36%.