Reuse of reclaimed asphalt concrete in Mosul roads construction

This paper presents an assessment of the possible reuse of asphalt concrete waste available in the city of Mosul-Iraq in road construction alone or with cement addition. Compaction, unconfined compressive strength (UCS), and California bearing ratio (CBR) tests were conducted on the Reclaimed Asphalt Pavement (RAP) with silty sand soil mixture (SM) used to improve grading to meet the grading A of general specifications for roads and bridges (SCRB) of (RAP/Soil of 92/8) %. Results show that the optimum moisture content (OMC), maximum dry density (MDD), UCS of RAP, and CBR will generally increase with the addition of cement. Longer curing periods will yield a higher strength. The OMC increases from 5 to 7.4%, and MDD increases from 1.972 to 2.13 g/cm3 when using 7% cement. The UCS of RAP stabilized with (1, 3, 5, and 7) % of cement for 7days are (11.25, 43.7, 70, and 73.57) kg/cm2 respectively and the CBR increases from 34% to (190, 260, 1150, and 2120) % when using (1, 3, 5, and 7) % of cement respectively. The obtained results confirm the possibility of using asphalt concrete waste in a sub-base layer after improving grading. Also, the possibility of using it in the base layer of roads after 2% cement addition, according to SCRB.