Recycling and Reclamation of Airfield Pavements

Transcription

1 Recycling and Reclamation of Airfield Pavements 35 th Airports Conference FAA Eastern Region, Hershey, PA April 4, 2012 Presented by: Mark D. McGuire, P.E.

2 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

3 Brief Introduction

4 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

5 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)

6 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)

7 Potential Applications / Recent Project Examples Re-Use of Materials on Site (RAP Stockpile) RAP stock pile location Calculating waste depends who you ask!

8 Potential Applications / Recent Project Examples Re-Use of Materials on Site Mix In Place Operations Cement Treated Aggregate / Base Course (Manassas Regional Airport)

9 Potential Applications / Recent Project Examples Re-Use of Materials on Site Mix In Place Operations Cement Treated Aggregate / Base Course Cement Added Mix In Place

10 Potential Applications / Recent Project Examples Re-Use of Materials on Site Mix In Place Operations Cement Treated Aggregate / Base Course (Burlington Int. Airport)

11 Potential Applications / Recent Project Examples Re-Use of Materials on Site Mix In Place Operations Cement Treated Aggregate / Base Course (Burlington Int. Airport)

12 Potential Applications / Recent Project Examples Re-Use of Materials on Site Mix In Place Operations Cement Treated Aggregate / Base Course (Burlington Int. Airport)

13 Project Specifications / FAA MOS Process RAP Specification FDR Specification DOT/FAA Order F Eastern Region 5300 Form

14 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

15 Equipment / Advancements / Videos (source: Wirtgen America) Ripped Asphalt Large slab feed. Often contaminated with dirt. Milled Asphalt When stockpiled it often clumps together.

16 Equipment / Advancements / Videos (source: Wirtgen America) Benefits of shape Road aggregate Flaky aggregates 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

17 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

18 Equipment / Advancements / Videos (source: Wirtgen America) Horizontal shaft impact crusher Primary, Secondary and Tertiary crushing. crushing ratio max. 15:1 advantages high production cubical shaped end product disadvantages high wear costs high content of fines large crushing ratio flexabile

19 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

20 Economic Impacts / Environmental Benefits

21 Economic Impacts / Environmental Benefits EXAMPLE CALCULATIONS RAP Base Course for Shoulders 2143 SY 12" Depth Recycled In Place CTA SY 10" Depth For Typical Full Depth Demolition & Removal Total Material Hauled Off Site At 8 Yards / Truckload 18,558 Cubic Yards 2,320 Truck Loads 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, lbs/ft3 Tonnage of cement 2,768 7% Fuel Burn for mining aggregate & cement $45,700 Energy Costs ($1.08/ton) 12,187 Approximate Fuel Fuel Burn for CTA mixing operations 1.2 gallons / ton Subtotal Fuel Burn 59,643 gallons $223,662 Fuel Savings

22 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

23 Economic Impacts / Environmental Benefits

24 Questions?