The NCAT Pavement Test Track was originally constructed as a result of interest and support from state Departments of Transportation (DOTs) who shared a concern for building and maintaining safe and cost effective pavement infrastructure. Track research operations began in the summer of 2000. Forty-six 200-ft test sections were subjected to 10 million equivalent September 1, 2017 single axle loadings (ESALs) of heavy truck traffic through December of 2002. Test sections were rebuilt in 2003, 2006, 2009, 2012, and 2015 with 10 million ESALs applied within each 3year research cycle. Positive experiences with implementable findings that reduce the life cycle costs of flexible pavements and facilitate rapid deployment of sustainable technologies have made Track research an outstanding investment for numerous state DOTs, who pool their resources to share the cost of construction, operations, and research in a cooperative manner. The summer 2018 rebuild is the starting point for the seventh research cycle, with many high reward research options available for potential sponsors. NCAT is again partnering with MnROAD in the 2018 research cycle to execute a pavement performance experiment with a nationwide implementation impact. Background information on the scope of the NCAT/MnROAD partnership is provided as an attachment.

The primary objectives of the pooled fund project described herein will be: 1. Constructing 200 ft test sections on the existing 1.7 mile NCAT test oval that are representative of in-service roadways on the open transportation infrastructure. Each section will be built precisely in accordance with the directives of the research sponsor. Consequently, the final experiment design will likely not be determined until just before the summer of 2018; 2. Applying accelerated performance truck traffic in the 2 years following construction, and extending traffic at the discretion of research sponsors on sections built in previous research cycles both on the NCAT test oval and at MnROAD for the duration of the 3-year research cycle. Design traffic for each unique research cycle on the NCAT test oval is 10 million equivalent single axle loadings (ESALs); 3. Assessing/comparing the functional and structural field performance of trafficked sections on a regular basis via surface and subsurface measures. Surface performance measures are comprehensive and MAP-21 compliant. Subsurface high-speed response measurements will be used to document how each structural section responds to passing loads as a function of temperature, age, and damage accumulation; 4. Validating/calibrating new and existing M-E approaches to pavement analysis and design using pavement surface condition, pavement load response, precise traffic and environmental logging, and cumulative damage. Calibration is essential to the successful implementation of AASHTOWare’s Pavement ME Design as well as other M-E design programs. Implementation without calibration often results in overly conservative designs; 5. Correlating field results with laboratory data for both mechanistic and preservation applications. Laboratory performance data that can predict long term preservation outcomes will provide DOTs with an additional mechanism for making rational selection decisions. State-of-the-art laboratory testing will be utilized, with a focus on balanced mix design; and 6. Answering practical questions posed by research sponsors through formal (i.e., reports and technical papers) and informal (e.g., one-on-one responses to sponsor inquiries) technology transfer. For example, can the same laboratory tests be used to screen both virgin and high binder replacement (i.e., higher RAP and RAS) mixes for cracking susceptibility for both mix design approval and quality control test applications? Support for implementation through the development of guide specifications, training, and technical support are research products.

The scope of work for the pooled fund project will include: 1. Hauling materials to the project from offsite locations. Material donations are typically secured by state sponsors, while reasonable hauling expenses are handled by the pooled fund; 2. Rebuilding sections in accordance with sponsors’ directives via competitively bid subcontracts administered by NCAT. It is anticipated that aggregate hauling, liquid asphalt supply and delivery, rental of select construction equipment, plant production, and mix placement may all be procured via competitively bid subcontracts; 3. Installing both environmental (i.e., multi-depth pavement temperature probes) and response instrumentation (i.e., high speed stress and strain gages) in new experimental sections; 4. Operating a 5-truck heavy triple-trailer fleet in order to apply accelerated truck traffic on the NCAT test oval following the completion of construction. Human drivers operate NCAT vehicles in order to best induce representative vehicle wander, but it is expected that autonomous vehicles will be implemented in the future. Interstate traffic is used to load test sections at MnROAD; 5. Measuring field performance each week when the fleet is parked to fully document the changes in surface condition as a function of traffic and temperature. High-speed pavement response will also be measured on a weekly basis. Pavement deflection and surface friction will be measured on a monthly basis; 6. Conducting laboratory testing to quantify basic material and mix performance properties, which will serve as the basis of performance model development; and 7. Comparing predicted and measured pavement response as well as predicted and measured cumulative pavement damage in order to validate then calibrate prevailing M-E methodologies.

This project is expected to be eligible for 100% SP&R funding. Each sponsor participating in the study is asked to contribute funding as a function of the scope of their selected research. The cost to participate varies as follows according to the amount of effort required: • Continue traffic on existing mill/inlay section – $80k / year ($240k / section) • Surface treatment on existing mill/inlay section - $80k / year ($240k / section) September 1, 2017 o Intended to provide access to project for private sector partners o Does not include the cost of materials, construction or mitigation o Commitment to rapid mitigation of failed experiments is required • Continue traffic on existing structural section – $100k / year ($300k / section) o This option also applies to participation in the cracking group (CG) study • Mill/inlay surface performance section – $150k / year ($450k / section) • Mill/inlay structural performance section - $180k / year ($540k / section) • Structural performance section – $210k / year ($630k / section) o This option also applies to participation in the innovation group (IG) study