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 reducing and predicting distresses in their flexible pavements. The 2009 NCAT Pavement Test Track is expected to consist of an even larger structural experiment as well as more mill/inlay surface mixes, with formal research sponsorship expanded to include private sector partners. Track research sponsors have always been encouraged to choose experiments that meet their specific research needs. Individualized test sections will still be optional on the 2009 Track; however, NCAT is also encouraging sponsors to consider supporting a pre-designed six section ¿Group Experiment¿ that is intended to encompass multiple timely issues that are important to the entire pavement community.
Additional details are available at http://www.pavetrack.com or in the attachment to this solicitation.
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;
2. Applying accelerated performance truck traffic in the 2 years following construction;
3. Assessing/comparing the functional and structural field performance of trafficked sections on a regular basis via surface and subsurface measures;
4. Validating the M-E approach to pavement analysis and design using both surface and subsurface measures;
5. 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;
6. Correlating field results with laboratory data; and
7. 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 high RAP content mixes provide the same level of performance as virgin mixes? If so, can they be used in both deep and shallow layers? Although warm mix is better for the environment, will it provide the same level of rut and moisture damage resistance as conventional mixes?
Scope of Work
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 supply and grade control of subgrades and bases, aggregate hauling, liquid asphalt supply and delivery, plant production, and mix placement may all be procured via competitively bid subcontracts. In order to reduce construction costs as much as possible, surplus equipment such as dump trucks, dozers, etc. will be provided by ALDOT in exchange for prescribed monthly usage fees. Any equipment that can not be obtained from ALDOT will be rented commercially to facilitate construction;
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 following the completion of construction. Actual human drivers pilot the vehicles in order to best induce representative vehicle wander;
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.
100% SP&R funding has been requested for this project. 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 ¿ $55k / year ($165k / section)
¿ Surface treatment on existing mill/inlay section - $55k / year ($165k / section)
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 ¿ $70k / year ($210k / section)
¿ Mill/inlay surface performance section ¿ $120k / year ($360k / section)
¿ Mill/inlay structural performance section - $150k / year ($450k / section)
¿ Structural performance section ¿ $180k / year ($540k / section)
¿ Group experiment - $180k / year ($540k total assuming 6 sponsors)
o Actual amount will be less if more than 6 sponsors participate
o For example, cost will be only $72k / year ($216k total) with 15 sponsors
Funding requirements are based on reasonable assumptions; however, if project costs increase significantly (e.g., fuel) either a proportionate amount of additional funding or a modified scope of work may be required. Please visit the project web at http://www.pavetrack.com for additional information.
Note: $1,620,000 of the commitments required will be funded by Shell Global Solutions (US)Inc. and Kraton Polymers, LLC, private industry supporters of this study.