Evaluation of Combined Excavation Waste and Reclaimed Asphalt Pavement Aggregates for Use in Road Bases and Sub-bases

Abstract

More than 15 million tons of aggregates are imported each year to Qatar from neighbouring countries. Large quantities of waste materials (around 20 million tons/year) from excavation waste, demolition rubble and reclaimed asphalt pavement (RAP) are being generated. The main objective of this paper is to present the results on the use of combined excavation waste (EW) and RAP aggregates in the construction of road bases and sub-bases. Physical and chemical properties were determined. Different combinations of both materials were subjected to compaction and California Bearing Ratio (CBR) testing in accordance with Qatar Construction Specifications. Results indicated that, for the materials tested, it is not feasible to use excavation waste, RAP aggregates or a combination of the two materials in road bases and sub-bases. The materials failed to meet some Qatari standards such as Los Angeles abrasion, liquid limit, plasticity index and CBR specified for road construction.