Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

Abstract

Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt with aggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and water with approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to 60% water plus some minor components. This study aims to use the cold emulsified asphalt mixtures for road construction and maintenance in Iraq as an alternative to the hot asphalt mixtures, due to its economical, practical and environmental advantages. This studyfocused to test and evaluates the emulsified asphalt material properties to be used as paving mixture. The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshall stability, wet Marshall stability, retained Marshall stability, flow tests and compared with the common used specification.The results indicate that the emulsified asphalt type cationic slow setting low viscosity (CSS-1) is very suitable with quartz type of aggregate from Al-Nibaay quarry. From many trial mixes it is found that the best percentages of initial residual bitumen content to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshall stability were ranged from (2.5%, 3%,3.5%,4% and 4.5%), andthe optimum percentage is (3.5%).Finally it can be conducted that the emulsified asphalt mixture is a suitable alternative mixture to the hot asphalt mixture for road construction and maintenance in Iraq.