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MnROAD | NRRA | Structure & Teams | Geotechnical Team

Determining Pavement Design Criteria for Recycled Aggregate Base and Large Stone Subbase

Status: Complete
Project Start Date: November 16, 2017
Project End Date: October 31, 2020

Project summary

Although recycled pavement materials have been used in roadway base layers for many years, a specific design method does not exist that describes how to build roadways with these materials. Many state Departments of Transportation (DOTs) assume recycled base materials behave similar to base layers built with conventional virgin aggregates (VA). There is a similar lack of an existing design methodology for pavement systems built with a large stone subbase (LSSB).

The proposed project has three main goals. The first goal of the project is to determine the field and laboratory performance of materials and test sections built with recycled aggregate bases (RAB) including recycled concrete aggregate (RCA), recycled asphalt pavement (RAP), and mixtures of these materials with VA. In addition, similar analyses will be conducted for the test sections built with 18 inches thick LSSB with different compaction methods (1-lift and 2-lift), and those 9 inches thick LSSB built with geogrids and geotextiles. To accomplish this goal, the research team will evaluate both the geomechanical and environmental properties of these pavement systems. It should be noted that the LSSB sections have only one type of aggregate base and the multiple recycled aggregate base sections do not have LSSB indicating that experiments for each different design methods are separate. The second goal of the project is to develop a method to estimate the stiffness and permeability of RAB and LSSB designs. This goal will be achieved by establishing correlations between common laboratory test data and both laboratory and field modulus and permeability values. The third goal is to prepare a pavement design and construction specification for roadways built with RAB and LSSB designs. This goal will be accomplished via a summary of the results of all tasks, taking into account the performance, cost benefits, and life cycle costs of these systems. The outcome of this research will optimize the use of recycled materials and LSSB designs, while maintaining pavement quality, resulting in cost savings and conservation of natural resources.

Project tasks

Original Need Statement: Recycled Aggregate Base and Large Subbase (DOC), 6/14/2017

Task 1: Literature review and recommendations

Task 2: Tech transfer “State of Practice”

Task 3: Construction monitoring and reporting

Task 4: Laboratory testing

Task 5: Performance monitoring and reporting

Task 6: Instrumentation

Task 7: Determine pavement design criteria

Task 8: Draft final report

Task 9: Final report

Project team

Principal Investigator: Bora Cetin, Michigan State University, cetinbor@msu.edu
Co-Principal Investigators: William Likos, Tuncer Edil, Ashley Buss, Halil Ceylan, Junxing Zheng
Technical Liaison: Raul Velasquez, MnDOT
Project Technical Advisory Panel (TAP)

  • Tim Andersen, MnDOT
  • Terry Beaudry, MnDOT
  • James Bittmann, MnDOT
  • Richard Endres, Michigan DOT
  • Thomas Fennessey, MoDOT
  • Ed Johnson, MnDOT
  • Jeff Horsfall, WisDOT
  • Deepak Maskey, Caltrans
  • Heather Shoup, IL DOT
  • John Siekmeier, MnDOT
  • Raul Velasquez, MnDOT

Related materials

Final report

Final Report, June 2021
Report Appendices, June 2021