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NRRA States have been diamond grinding concrete pavements for many years traditionally as a preservation treatment to improve smoothness and/or enhance friction and in new construction to meet contract requirements and avoid penalties. More recently diamond grinding has used for noise reduction. NRRA States that use diamond grinding have conducted research that can add to the collective knowledge base of this process and performance. This project explores the state of practice of diamond grinding PCC surfaces and the benefits.

Due to increased traffic congestion and reduced budgets, National Road Research Alliance (NRRA) states are seeking effective rehabilitation techniques for older concrete pavements. Unbonded concrete overlays have a successful history as a rehabilitation option, and there is interest by NRRA member states to assemble information on best practices for the design, construction, and maintenance that relate to field performance. The goal of this project is to produce a brief technical document synthesizing the design, construction, maintenance, best practices, and performance observations of unbonded concrete overlays in NRRA member states.

Significant improvements have been made in base stabilization practice that include design specifications and methodology, experience with the selection of stabilizing additives, and equipment for distribution and uniform blending of additives. For the rehabilitation of existing pavements the stabilization of base material has delivered performance as good as or better than reconstruction at a reduced cost. Many additive products exist to stabilize base materials for roadway construction, but it is not always clear which additive is the right one to use. This guidebook intends to focus on stabilization for new construction and Stabilized Full Depth Reclamation (SFDR) and to help with the selection of suitable nonproprietary stabilization additives for individual specific project(s).

Recycled Asphalt Pavement (RAP) is encouraged to be used in the construction of new roadways and pavements. Its use reduces cost and environmental impacts of road construction by reusing existing asphalt pavement. In Minnesota existing asphalt pavement material is often crushed and blended with other aggregates to create aggregate base or shouldering materials or transported to an Asphalt plant, crushed, and incorporated into new asphalt material. Both strategies reduce demand for virgin aggregates. Incorporation into new asphalt material has the additional benefit of reducing demand for asphalt binder material. It is recognized that a greater benefit to the environment and economy can be realized when incorporated into new asphalt material. This document was developed as a reference for local agencies that have minimal knowledge of incorporating RAP material into new asphalt and would like to understand more.