A Laboratory Study on Open and Dense Graded Cold Asphalt Emulsion Mixtures for Surface Courses

Cold Asphalt Emulsion Mixture (CAEM) is considered as an eco-friendly asphalt
mixture because it eliminates the emission. It is produced at ambient temperatures and
reducing the requirement to heat aggregates and bitumen prior to mixing process, so it is good
for energy saving in pavement construction. In application, there are two type gradations of
aggregate for cold asphalt mixture, dense gradation and open gradation. A series of laboratory
works were conducted to analyse the performance of dense and open graded cold mixture for
surface courses, which is the main objective of this study. Marshall Samples were kept indoor
at room temperature for 7 days prior to Marshall Test to obtain the effect of curing process for
cold mixtures. All samples were tested using Marshall Tests for stability and flow. The results
show that dense graded mixtures need less bitumen content than open graded mixtures. For
cured samples, dense graded mixtures produces higher Marshall Stability than open grades
mixtures, while uncured samples have almost the same Marshall stability value for both
gradations. For open graded mixtures, curing process reduce the porosity of mixtures.