Evaluate the strength of cement treated recycled construction and demolition aggregates as a pavement material

Abstract

Generation of construction and demolition (C&D) waste is a part of urbanization and causes adverse effect on the environment. The most popular method of managing C&D waste is through disposal in landfills which is becoming an environmental hazard. Therefore, use of such waste as recycled aggregate in road construction will make more benefits in environmental and economic aspects. However, lack of research on properties and performances of recycled C&D has limited its use in pavement structures in many developing countries including Sri Lanka. This study discusses the possibility to partially replace conventional aggregates with recycled C&D aggregate in base or sub base road construction. Test samples were made by mixing C&D aggregates in different ratios with conventional aggregates. Tests were carried out for particle size distribution (PSD) and dry density - moisture content relationship. California bearing ratio (CBR) was conducted to better understand the bearing strength of recycled mixtures. The study further extended by adding cement to evaluate the improving range in strength. The resulted high strength properties of the C&D mixed samples revealed the potential use of recycled C&D aggregates as an alternative for conventional aggregates in road construction.