High Performance Concrete Pavements
CHAPTER 31. TENNESSEE 1 (I-65, Nashville)
Over the past decade, significant progress has been made in the development of performance-related specifications (PRS) for the acceptance of newly constructed jointed plain concrete pavement (JPCP). A PRS is able to relate the construction acceptance quality characteristics (AQCs) (e.g., smoothness, thickness, strength, air content, and percent consolidation around dowels) to the levels of expected pavement performance and future life cycle costs (LCCs), thus providing the basis for rational acceptance and price adjustment decisions. The PRS methodology has been verified through the use of shadow specifications on actual construction projects.
In this study, the Tennessee Department of Transportation (TDOT) is implementing PRS on a field trail basis under an FHWA contract. Should the implementation of PRS in this project be successful, TDOT would be able to use PRS in more projects without outside assistance and would be able to achieve the full benefits of PRS.
The main objective of this project is to evaluate the practicality and effectiveness of PRS for JPCP based on a real-world field trial in Tennessee. The long-term benefits of PRS expected to be derived from this project include (Gharaibeh 2003) :
- Better linkage between design and construction.
- Higher quality pavements (through incentives).
- Testing that focuses on key quality characteristics that relate to the pavement's long-term performance.
- Incentives and disincentives that are justified through reductions or increases in life cycle costs.
- Specifications that give contractors more flexibility, responsibility, and accountability.
- Incentive to contractors to be more innovative and more competitive.
- Lower "fear factor" for contractors and less administrative complexity for the agency than warrantees.
Project Design and Layout
TDOT provided the following candidate projects for the implementation of PRS (Gharaibeh 2003) :
- I-65 north of Nashville. This project is ongoing and consists of widening a 5.6-km (3.5-mi) long roadway from 6 to 10 lanes, with the existing concrete pavement to be reconstructed. Paving is expected to take place in March or April 2004.
- I-75 north of Chattanooga and I-65 north of Nashville. These projects are expected to be let in December 2004. However, paving could take place 2 to 3 years after letting.
After a project coordination meeting, it was recommended to TDOT that the most practical option is to implement PRS on a portion of the ongoing I-65 project.
State Monitoring Activities
No final decisions have been made regarding the State monitoring activities.
Acceptance test results from three concrete pavement projects that were constructed in Tennessee in the past 5 years were obtained and analyzed. The project-wide results are summarized in Table 49. These results will assist in establishing the target values (mean and standard deviation) for the PRS project, considering the quality levels achieved in these past projects (Gharaibeh 2003).
Table 49. Summary of Past Concrete Pavement Projects in Tennessee
|ATTRIBUTE||PROJECT 1||PROJECT 2||PROJECT 3|
|Tennessee Department of Transportation Identification||S.P. 33003-4154-04 (Contract No. 4359)||IM-40-2(71)87,57001-8172-44 (Contract No. 4559)||NH-I-75-1(95)3,33005-3161-44 (Contract No. 5356)|
|Location||I-24, Hamilton County||I-40, Madison and Henderson Counties||I-75, Hamilton County|
|Approximate length, mi||2.76||8.02||3.2|
|28-day compressive strength, lbf/in2||Field average||6432||5247||6046|
|Field standard deviation||892||315||625|
|Specifications||Min 3000||Min 3000||Min 3000|
|Thickness, in.||Field average||N/A||N/A||12.04|
|Field standard deviation||N/A||N/A||0.11|
|Air content, %||Field average||5.46||5.11||5.14|
|Field standard deviation||0.51||0.11||0.44|
|P.I, in./mi||Field average||2.55||N/A||2.53|
|Field standard deviation||0.88||N/A||0.71|
Point of Contact
Federal Highway Administration
Office of Infrastructure
Office of Pavement Technology (HIPT)
1200 New Jersey Avenue SE
Washington, DC 20590
Gharaibeh, N. G. 2003. Performance-Related Specifications (PRS) Field Trial in Tennessee. Quarterly Progress Report to the Federal Highway Administration.