Simple Procedure to Assess Performance and Cost Benefits of Using Recycled Materials in Pavement Construction

Abstract

The use of recycled materials in pavement engineering has a great potential to benefit our society in terms of reducing demands on natural pavement materials, reducing environmental problems, and conserving energy. However, pavement design/construction practitioners often hesitate to use recycled materials due to the lack of cost benefit and performance information. This paper presents a simple approach to evaluate economic effects of using recycled materials in pavement construction based on in situ pavement testing procedures. These testing procedures, including dynamic cone penetrometer, California bearing ratio, Dynaflect, and falling weight defelectometer, are commonly employed by state highway agencies. A full-scale accelerated pavement test section was built to investigate the performance of different base course materials: Louisiana Class II crushed limestone, foamed-asphalt-treated recycled asphalt concrete, fly-ash-stabilized blended calcium sulfate (BCS), and BCS stabilized with the 120 grade ground granulated blast furnace-slag (GGBFS). Among these base materials, GGBFS-stabilized BCS was found to have the highest strength and stiffness. On the basis of these field testing results, life-cycle cost analyses showed that the GGBFS-stabilized BCS provides a durable and cost-effective alternative to traditional pavement base materials.