Pavement Subgrade Stabilization Using Recycled Materials

摘要

The performance of subgrade stabilization with cement, lime or lime/fly ash are extensively studied. However, the use of recycled materials for subgrade stabilization is yet to be properly studied. If proper mix designs and construction specifications for subgrade stabilization with recycled materials are available, those materials can be used for pavement construction. Recycled materials not only provide cheaper alternatives for subgrade stabilization, they also alleviate landfill problems. Most of the previous studies were related to subgrade modification with recycled materials, limited to quantify immediate benefit through construction facilitation. However, there is a need to identify the long-term benefits and/or associated risks to use recycled material for subgrade stabilization. With satisfactory long-term benefits, subgrade stabilization can be potentially used for optimizing pavement designs that will result in cost effective pavement sections. If this study reveals any long-term risks associated with subgrade stabilization, those will be addressed by either remedial actions or by limiting usage of those stabilizing materials. This paper examines the preliminary results of a laboratory testing program to determine benefits and risks of using recycled materials such as Cement Kiln Dust (CKD), Lime Kiln Dust (LKD), Fly Ash (FA) and Concrete Fines (CF) for subgrade modification as well as stabilization.