Compaction and cbr properties of reclaimed asphalt pavement mixed with sand

The use of recycled materials for construction is beneficial to both the environment and the economy. Reclaimed asphalt pavement (RAP) is one of the most commonly used recycled materials. RAP is most commonly used as an aggregate substitute in asphalt mix. It is also used as granular sub-base or base aggregate and embankment or fills material. The objective of this study was to evaluate the effect of the addition of sand to (RAP), on the compaction and strength of it. To achieve this objective of the study, five large pieces of asphalt cubes were collected from three different places (Maxmwr, Shaqlawa, Mosul street) in Erbil City/Iraq and experiments were conducted to find out their densities, water absorption, compressive strength and particle size distributions, RAP sample were mixed with 5%, %10, 15%, 20%, 25%, 50% by weight of poorly graded sand. Modified compaction, Soaked and Un-soaked CBR tests were performed on each mix, The modified proctor test were performed according to ASTM D 1557 for different sand/RAP mixtures, the results showed that increasing sand content in RAP caused an increase in maximum dry density (MDD) and optimum moisture content (OMC) of mixtures. Soaked and Un-soaked California bearing ratio test (CBR) was conducted at OMC for each mix. The results revealed that the increase in sand content for RAP samples resulted in an increase of CBR values for soaked and unsoaked samples. The RAP samples derived from different sources had different densities, water absorption and compressive strength values. None of the tested samples met the CBR requirements of the AASHTO Standards to be used as base or subbase.