Unconfined Compressive Strength of Chemical Stabilised Recycled Asphalt Pavement (RAP) and Crusher Run Mixture for Road Base Course Application

Abstract

Due to depletion of natural resources and rising awareness of environmental preservation, the road construction practitioners are always seeking alternative materials and technology to make the industry more sustainable in pavement construction. This paper examines the chemical stabilisation of Recycled Asphalt Pavement (RAP) materials and Crusher Run (CR) mixtures with a proprietary chemical binder as a potential way forward. The materials were mixed in ratios of 0, 25, 50, and 75% RAP replacement of CR, with the chemical stabiliser added in dosages between 2-4% per dry weight of the materials. Compacted and cured for 7 days as per requirements of the local authority, the samples were then subjected to the Unconfined Compression Test where the strength UCS (qu7) was recorded. Triple samples were tested for each case to ensure reliability of the results obtained. It was found that with RAP substitution, the UCS is inversely proportionate to ratio RAP used in the mixture, while UCS is directly proportional to dosage chemical added. Besides, It is technical viable to partially replace CR with RAP during chemical stabilization for road base course application.