Compaction test of the recycled aggregate mixture with different particle size was conducted, and the influence factors of the optimum moisture content (
wopt) and the maximum dry density (
ρmax) were analyzed. Considering such three effective factors including aggregate amount, cement amount and fly ash amount, the compaction test was conducted using orthogonal experimental design. The primary relationship for the influence of the optimum moisture content and maximum dry density was analyzed by the extremum difference analysis.