This document discusses the use of precast concrete panels (PCP) for repairing and rehabilitating high-traffic concrete and asphalt pavements. PCP allows for rapid renewal with short lane closure times and improved work zone safety. Nominal reinforcement and pre-tensioning of panels reduces thickness and allows for wider/longer panels. Proper bedding and leveling of panels is important for performance. PCP can provide 15-20 years of service for repairs or 40+ years for continuous applications. States commonly use PCP for heavily traveled interstates, ramps, intersections and other critical locations requiring minimal traffic disruptions.

1. Precast Concrete for Rapid Repair and
Rehabilitation of High Traffic-Volume
Concrete and Asphalt Pavements
39th Annual Concrete Paving Workshop
January 16-17, 2018
Lincoln, Nebraska
Samuel Tyson, P.E.
Federal Highway Administration
Washington, District of Columbia

2. Precast Concrete Pavement (PCP)
• High Traffic Volumes
• Alternate Route Availability
• Rapid Renewal
• Lane-Closure Times
• Work-Zone Safety
• Opening to Traffic
• Concrete Quality
• Long-Life Performance

3. Highway Agencies in USA
Used PCP
PCP in Progress

4. Reinforcement & Prestressing
• Nominal reinforcement (0.12-0.15 %)
for handling stresses & to control
potential cracking.
• Pre-tensioning by fabricator allows
reduced panel thickness.
• Pre-tensioning also for wider and
longer panels (e.g., two-lane width).
• Post-tensioning applied on site to
connect a series of panels.

5. Bedding Support for PCP Systems
Uniform support key to PCP performance
• Existing base graded and compacted
• New base material
• Cement-treated
• Rapid-setting lean concrete
• Undersealing
• Rapid-setting grout
• Polyurethane

6. Base Preparation & Panel Leveling
• Trimming of Stabilized Base – Time-
consuming activity.
• Thin Shims – Typically requires
lifting of panels to adjust shims.
• Polyurethane Foam Injection –
Specialized equipment required.
• Fast-Setting Lean Concrete – Partial
removal of base and screeding.
• Leveling Bolts – Rapid and accurate.

7. Trimmed base with 0.5-inch (12-mm)
bedding layer of cemented fine-grained
granular material

8. Typical Leveling Bolts

9. Leveling Bolt & Grout Ports
During Concrete Placement

10. Panel-to-Base Contact
• Panels Installed Directly on Base
–Grout injected through ports to fill
any voids.
–Panel raised to grade by injection
of polyurethane foam.
• Panels Installed with Leveling Bolts
–Grout fills 0.5-in. (12 mm) gap
between bottom of panel and base.

11. Load Transfer Slots & Dowels
for Jointed PCP Systems

12. • Repair Applications
o Nominally reinforced panels routinely used
o Pre-tensioned panels if longer/wider
dimensions
• Continuous Applications
o Jointed PCP systems
 Nominally reinforced
 Pre-tensioned panels
o Post-tensioned systems
 Nominally reinforced panels
 Pre-tensioned panels
 Fewer active joints and longer sections
PCP Applications

13. PCP Applications (continued)
• Repair Applications
–Service-life of 15 to 20 years is
predicted for PCP repairs.
–Existing pavement may need to be
reconstructed prior to 15 years.
–Exceeds 8 to 10 years experienced
with rapid-hardening concretes.

14. Single Panel for Full-Depth Repair
Dowels for Load Transfer

15. PCP Applications (continued)
• Continuous Applications
–Service-life of 40+ years.
–No early failures or materials-
related distress.
–Reduced potential for cracking,
faulting & spalling.
–Smoothness and surface texture
initially good & easily maintained.

16. Rapid Replacement of Rutted Asphalt Ramp.

17. Continuous Applications –
Dowel slots top/bottom for load transfer
Jointed

18. Continuous Application –
Post-tensioned

19. Typical Uses/Nighttime Work
• Principal Uses
oHeavily-traveled interstate and primary
roadways – Critical need in all States.
oInterstate and urban ramps – Often no
convenient alternate routes.
• Special Uses
oIntersections – Traffic delays minimized.
oBridge approaches – Smooth transition
from pavement to bridge.
oBus pads – Avoid disruption of service.
oAirfields – A developing application.

20. Delaware DOT –
Outside Lane and
Shoulder/Right-Turn
Lane
Left-Turn
Lane

21. Virginia DOT –
3 Lanes and
Outside
Shoulder/Rush-
Hour Lane

22. Virginia DOT –
Outside Lane of
Exit Ramp

23. Hawaii DOT – Full-Depth
Repair of 5 Lanes and
Outside Shoulder/Right-
Turn Lane

24. Texas DOT – Reconstruction of
Industrial Intersection in
Energy Sector

25. Surface Finishing
• Vertical tolerances with routine
leveling methods may or may not
be satisfactory for high-speed
roadways.
• Grinding may be needed for
smoothness due to vertical
differences at transverse joints.
• Smoothness and surface texture
achieved on-site with grinding.

26. • Panel fabrication rate –
–Inside plant; 10 panels/day.
–Pre-stressing bed; 30 panels/day.
• Panel installation rate –
–Repair; 20 panels/night.
–Continuous; 50 panels/night.
• Inventory – Several weeks (or months)
of panel production is needed before
installation on project can begin.
Panel Fabrication/Installation Rates

27. Precast Panel Fabrication
Outdoor Prestressing Bed for
Multiple Panel Production
Typical Reinforced
Panel Production

28. • Experience in the USA with PCP
systems is limited to 16 years.
• PCP systems are rapidly installed.
• PCP systems provide long-term
performance following satisfactory
design, fabrication and installation.
• Fabricators & contractors having
no prior experience are producing
and installing panels satisfactorily.
Summary