Effect of Residual Asphalt Content on Creep Strain of Cement Modified Emulsified Asphalt Mixtures

Objective of this paper is to determine the rutting performance of residual asphalt content on cement modified emulsified asphalt mixtures at heavy duty highways. For this purpose, emulsified asphalt specimens with dense graded aggregate were prepared according to Marshall method for emulsified asphalt-aggregate cold mixture design. The specimens were prepared in such a way that portland cement was substituted for mineral filler in an increased percent from 0 % to 6 %. In this way, three asphalt emulsion mixtures with different residual asphalt contents of 4.2 %, 5.2 %, and 6.2 % by the mass of dry aggregate were produced. Static load asphalt creep tests were performed on the specimens. Based on the experimental work, it has been reached that dense graded cement modified emulsion mixtures are of great performance in rutting compared to hot mixtures with the same aggregate grading and bitumen content. Results showed that cement acts as a secondary binder in emulsion mixture. Creep and permanent deformation resistance are all improved by portland cement addition but the resistance to creep deformation of emulsion mixture was decreased by the increase of residual asphalt content.