Guidance, parameters, and recommendations for rubblized pavements

Abstract

The objectives of this research project were to document historical information and data on the rubblization projects that have been built in Wisconsin; to provide guidelines and recommendations for the selection, design, testing, and construction of rubblized portland cement concrete (PCC) slabs; and to determine the conditions for which rubblizing PCC pavements is a feasible rehabilitation strategy. Two documents were prepared as a result from this study ? the main research report (presented herein), and the appendices. Appendix A summarizes the design criteria and construction suggestions for rubblized projects and Appendix B includes the catalog of rubblized projects built in Wisconsin between 1990 to 2003. The research study included a review of existing literature and an analysis of rubblization projects built in Wisconsin to determine the performance characteristics and expected service life of rubblized PCC projects. The performance analyses included a comparison of the condition of hot mix asphalt (HMA) overlays placed over intact and rubblized PCC pavements, and an extrapolation of the expected service life of the rubblized PCC pavements using empirical-mechanistic type relationships. The average elastic modulus of the rubblized PCC layer was estimated to be 65,000 psi and was based on matching the predicted to observed pavement performance of the Wisconsin rubblized projects. An American Association of State Highway and Transportation Officials (AASHTO) structural layer coefficient of 0.22 was also determined and recommended for use in designing rubblized projects in Wisconsin. Based on these performance analyses, the rubblized PCC projects are expected to equal or exceed the design life of this rehabilitation strategy. This rehabilitation strategy is recommended for continued use in Wisconsin under those conditions conducive for rubblization. In addition, recommendations were provided for the continued monitoring, sampling, and testing (nondestructive and destructive) of existing and future rubblization projects to confirm the recommendations from this study.