Recycling and Reclamation of Airfield Pavements

Recycling and Reclamation
of Airfield Pavements
35th Airports Conference
FAA Eastern Region, Hershey, PA
April 4, 2012
Presented by: Mark D. McGuire, P.E.
Items for Discussion
•
•
•
•
•
•
•
Brief Introduction (Mark McGuire, P.E. C&PE)
Potential Applications / Recent Project Examples
Construction Specifications / FAA MOS process
Mix Designs / Construction Schedules
Equipment / Advancements / Videos - References
Economic Impacts / Environmental Benefits / ACRP 42
Questions
Brief Introduction
Brief Introduction
•
•
•
Recycling existing Bituminous Concrete, Portland Cement Concrete, and Crushed
Aggregate Materials
Mobile Jaw Crushers / Mobile Impact Crushers
Mobile Screens / In-Place Recyclers / Mobile Secondary Crushers
Potential Applications / Recent Project Examples
•
Re-Use of Materials on Site
• RAP – as a base course / aggregate substitute (D-754 ditches)
• RAP material condition assessment (binder) – may be more valuable at mixing
plant ($10 per ton)
Potential Applications / Recent Project Examples
•
Re-Use of Materials on Site
• RAP – as a base course / aggregate substitute (P-610 ditches)
• RAP material condition assessment (binder) – may be more valuable at mixing
plant ($10 per ton)
Potential Applications / Recent Project Examples
•
Re-Use of Materials on Site (RAP Stockpile)
• RAP – stock pile location
• Calculating waste – depends who you ask!
Potential Applications / Recent Project Examples
•
Re-Use of Materials on Site – Mix In Place Operations
• Cement Treated Aggregate / Base Course (Manassas Regional Airport)
Potential Applications / Recent Project Examples
•
Re-Use of Materials on Site – Mix In Place Operations
• Cement Treated Aggregate / Base Course
•
•
Mix In Place
Cement Added
Potential Applications / Recent Project Examples
•
Re-Use of Materials on Site – Mix In Place Operations
• Cement Treated Aggregate / Base Course (Burlington Int. Airport)
Potential Applications / Recent Project Examples
•
Re-Use of Materials on Site – Mix In Place Operations
• Cement Treated Aggregate / Base Course (Burlington Int. Airport)
Potential Applications / Recent Project Examples
•
Re-Use of Materials on Site – Mix In Place Operations
• Cement Treated Aggregate / Base Course (Burlington Int. Airport)
Project Specifications / FAA MOS Process
•
RAP Specification
•
FDR Specification
•
•
DOT/FAA Order 5300.1F
Eastern Region 5300 Form
Mix Designs / Construction Schedules
•
Access to Site to Obtain Material
•
Specification requirements for mix designs: open to interpretation or strict
requirements?
•
Does the schedule account for the laboratory time to process the mix designs?
•
Initial paperwork Milestone: QC Plan, Construction Schedule, Submittals, & Mix
Designs
Equipment / Advancements / Videos (source: Wirtgen America)
Ripped Asphalt
• Large slab feed. Often
contaminated with dirt.
Milled Asphalt
• When stockpiled it often clumps
together.
Equipment / Advancements / Videos (source: Wirtgen America)
Benefits of shape
Flaky aggregates
Road aggregate




Better compaction
Improved mechanical properties
Better layer’s stability
Better wear resistance
Elongated
aggregates
Concrete aggregate




Better flow ability
Better compaction
Better quality
Less cement and water
Cubical aggregates
Equipment / Advancements / Videos (source: Wirtgen America)
Jaw Crusher
7:1 reduction ratio = 25” feed reduced to 3.5” final product size
Horizontal Shaft Impact Crusher
15:1 reduction ratio = 25” feed reduced to 1 ½” final product size
Vertical Shaft Impact Crusher
4:1 reduction ratio = 3” feed reduced to ¾” final product size
Cone Crusher
5:1 reduction ratio = 4” feed reduced to 13/16” final product size
Equipment / Advancements / Videos (source: Wirtgen America)
Horizontal shaft impact crusher
Primary, Secondary and Tertiary crushing.
•crushing ratio max. 15:1
advantages
disadvantages
•high production
•high wear costs
•cubical shaped end product
•high content of fines
•large crushing ratio
•flexabile
Economic Impacts / Environmental Benefits
SOCIAL, ECONOMIC, AND SUSTAINABLE DESIGN CONSIDERATIONS
Typical Recycling or Mix in Place operations have the following benefits:

Eliminate operations associated with full depth demolition and removal of pavement section

Eliminate off-site hauling operations

Reduce risk and potential delay associated with subgrade exposure

Alleviate construction efforts required for achieving compaction of problematic subgrade

Eliminate necessity for quarry to produce virgin aggregate material

Eliminate batch plant operations for new material (if applicable)

Eliminate hauling operations associated with importing new material

Simplified construction methods requiring less equipment and man-power to complete construction
Economic Impacts / Environmental Benefits
Economic Impacts / Environmental Benefits
EXAMPLE CALCULATIONS
RAP Base Course for Shoulders
Recycled In Place CTA
2143 SY
66809 SY
For Typical Full Depth Demolition & Removal
Total Material Hauled Off Site
At 8 Yards / Truckload
18,558 Cubic Yards
2,320 Truck Loads
12" Depth
10" Depth
Quarry Production of Aggregate and Batch Plant Mixing of Cement Treated Aggregate
Amount of cement treated aggregate (CTA) required
520,355 Cubic Feet
Total Tonnage of CTA
39,547 Tons
@ 152lbs/ft3
Tonnage of cement
2,768 Tons
@ 7%
Fuel Burn for mining aggregate & cement
$45,700 Energy Costs ($1.08/ton)
12,187 Approximate Fuel Burn @$3.75/gal
Fuel Burn for CTA mixing operations
47,456 @ 1.2 gallons / ton
Subtotal Fuel Burn
59,643 gallons
$223,662 Fuel Savings
Economic Impacts / Environmental Benefits
Demolition & Removal Activities (Base Course) ‐ Dump Truck Activities
Total Traversed Expended Fuel Diesel Price Destination of Disposed Materials
Miles
(gallons)
($3.75 / gallon)
Alternate # 1 ‐ 1 Mile (2 Miles Round Trip)
4,640
1,031
$3,866
Alternate # 2 ‐ 6 Miles (12 Miles Round trip)
27,837
6,186
$23,198
Alternate # 3 ‐ 20 Miles (40 Miles Round Trip)
92,790
20,620
$77,325
Assume 4 MPG Loaded / 9 MPG Unloaded
Assume Asphalt Material is recycled as RAP during typical full depth demolition / removal activities
Virgin Material Used to Replace Removed Material (Base Course)
Total Traversed Expended Fuel Diesel Price Source of Virgin Material
Miles
(gallons)
($3.75 / gallon)
Nearest Quarry ‐ 11 Miles (22 Miles Round Trip)
51,035
11,341
$42,529
Alternate # 1 ‐ 1 Mile (2 Miles Round Trip)
4,640
1,031
$3,866
Alternate # 2 ‐ 6 Miles (12 Miles Round trip)
27,837
6,186
$23,198
Alternate # 3 ‐ 20 Miles (40 Miles Round Trip)
92,790
20,620
$77,325
Assume 4 MPG Loaded / 9 MPG Unloaded
According to EPA, 22.2 pounds CO2 / Gallon Diesel
77,170 Gallons
1,713,178 Pounds CO2 Eliminated
$289,388 Fuel Cost Savings
Economic Impacts / Environmental Benefits
Questions?