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The objective of this project was to document data for further development and refinement of QC/QA specifications and procedures, enhancement of material property based compaction requirements, development of statistically based requirements and tests, and further development of the link between mechanistic-empirical pavement design and construction. This report details the field and laboratory test results and analyses of the tests performed. A summary of the following tests results is included: intelligent compaction, light weight deflectometer, dynamic cone penetrometer, falling weight deflectometer, nuclear gauge, moisture testing, Proctor, Atterberg limits and gradation. The report consists of the following topics: Background and Data Summary, Intelligent Compaction Data, Falling Weight Deflectometer (FWD) Data and Companion Test Data. These data are synthesized, compared and correlated. Some of the observations are that the LWD, DCP and nuclear gauge are sensitive to material properties in a relatively thin surface layer of the material, in comparison to the relatively great thickness of material sensed by an IC roller. Also, the various materials and test types are sensitive to material moisture in differing ways. A strong correlation between IC data and small scale point test was not expected for at least three reasons: wide material variations, varying depth sensitivity, and varying material moisture sensitivity. This report confirms this expectation and further clarifies the value of continuous compaction control for contractor quality control. The report also confirms the value of the LWD and DCP for quality assurance by the agency/owner.

Full-depth reclamation (FDR) as a rehabilitation method improves the service life of pavement structures by reusing asphalt materials, thereby reducing costs and allowing for conservation of nonrenewable resources. However, the lack of mechanicsbased material testing procedures and performance-based specifications limit the use of FDR processes. First, the FDR design and construction process are presented, then, a literature review focusing on FDR research is completed, and a survey is conducted to obtain relevant information regarding current FDR practices in Minnesota. Next, Indirect Tensile Test (IDT) and Dynamic Modulus Test in IDT mode testing is performed on four FDR materials: Field mixed, Lab compacted; Lab mixed, Lab compacted; FDR with cement additive; and FDR with graphene nanoplatelet (GNP) additive. Two curing times are used to determine how physical properties change over time. Test results are used to perform simulations in MnPAVE software and a Life Cycle Cost Analysis (LCCA). Laboratory observations indicate that cement additive reduces predicted life and increases critical cracking temperature with a slight increase in cost; GNP additive reduces predicted life but also reduces critical cracking temperature with a significant cost increase; Lab mixed samples performed better than Field mixed, suggesting that field methods could be improved; and curing has a positive effect on the FDR materials with cement and GNP additives--for both materials, the dynamic modulus increase, and the GNP samples also had a slight increase in tensile strength. MnPAVE simulations and LCCA results indicate that over a 35-year period, FDR may be a more cost-effective method than traditional mill and overlay.

Pothole repairs continue to be a major maintenance problem for many highway agencies. There is a critical need for finding long-lasting; cost-effective materials and construction technologies for repairing potholes. This research effort investigates critical components associated with pothole formation and pothole repair and proposes solutions to reduce the occurrence of potholes and increase the durability of pothole repairs. The components include investigating and documenting pavement preservation activities; experimental work on traditional repair materials as well as innovative materials and technologies for pothole repairs; stress analysis of pothole repairs to identify whether certain geometric configurations are more beneficial than others; evaluating cost analyses to determine the effectiveness of various repair methods. A number of conclusions and recommendations were made. Potholes are mainly caused by the delayed response to timely fixing common pavement distresses. The state of Minnesota has a number of preservation strategies that are available and have been successfully used. Recommendations are made to improve these strategies using documents made available as part of new Every Day Counts; EDC-4; initiative. Currently; there are no required specifications for patching materials. Mechanical testing can be used to select patching materials based on the estimated durability of the pothole repair; such as short-; medium-; and long-term. A number of new materials and technologies are available for more durable solutions for winter pothole repairs; however; they require additional heat source and are more expensive.