FAA Airport Pavement Technology Program

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FAA Airport PavementTechnology Program

• National Airport Pavement Test Facility, FAA
  William J. Hughes Technical Center, Atlantic
  City, New Jersey, U.S.A.
• New PCC Test Items
• Pavement Thickness Design Software
• www.airporttech.tc.faa.gov

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New Concrete Mix Design

• 5.2 MPa (750 psi) or lower flexural strength to
  maximize thickness and minimize tendency for
  corner cracking due to curl (minimum 4.1 MPa (600
  psi)).
• Final mix has 50 percent cement replacement with
  flyash.

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Single Test Slab Placement

• Gain experience with high volume flyash mix
  placement and finishing.
• Measure curling of cured slab.
• Further refine instrument installation from that
  done in previous test strip.
• Monitor procedures for test item curing and early
  age behavior.
• Develop field curing methods.

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Placing Test Slab
Finished Slab
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Field Curing of Slab, Beams and Cylinders

• Soaker hoses
• Burlap
• Plastic
• Automatic timer for water
• Wet cure for 28 days

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Results from Test Slab

• Experience in placing the high flyash concrete
  mix.
• Instrumentation installation procedures
  satisfactory.
• Low heat of hydration with fairly uniform
  temperature profile during first 24 hours.
• Curling minimal during 28-day cure.
• Curling significant after removal of burlap and
  during drying period.

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Remaining Plans for CC2

• Continue monitoring test slab behavior.
• Place three concrete test items on 8 CBR
  subgrade.
• One on grade (concrete placed by 1/30/04).
• One on aggregate subbase (concrete placed by
  1/30/04).
• One on econocrete subbase (concrete placed by
  3/12/04).
• Subgrade and support placement complete.
• Instrumentation complete and installed.

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CC2 Test Objectives

• Compare life and performance for 4-wheel and
  6-wheel traffic.
• Compare life and performance for three different
  support conditions.
• Obtain data on SCI versus repetitions to failure.
• Compare interior and edge stresses.
• Measure shrinking/warping.

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Tilling Subgrade
Rolling Subgrade
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Forms for 20-Slab Test Item
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Placing Test Item Slabs in a
Checker-Board Pattern
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Installing Strain Gages at Slab Center
Strain Gages Installed at Slab Edge
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Pavement Software Products
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All checked programs available on
www.airporttech.tc.faa.gov