Performance Monitoring of Olmsted CR 117 and 104 and Aggregate Base Material UpdateStatus: CompleteReport Date: 06/22/2015 Summary: Researchers continued monitoring of Olmsted County Road 104 and CR 117 to evaluate the effect of limestone aggregate base particle size on pavement performance. They found that a Class 5 modified aggregate base allowing larger top-size limestone particles performs better than standard Class 5 aggregate and another permeable aggregate base. MnDOT has updated its standard specifications to allow a new gradation category named Class 5Q, which reflects the Class 5 modified base used in section 3. Olmsted and other southern Minnesota agencies are using Class 5 modified bases on projects. Final Deliverables: Report #2015-28 Research Summary Related Materials: Related Research: