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Recycled Asphalt Program & Environmental Stewardship Program ( Post Consumer Content). Robert C. Rea Nebraska Department of Roads WASHTO – Omaha, Nebraska April 2014. Average RAP Contents (Overall). 39.2%. 37.3%. 34.4%. 28.6%. 27.3%. 6.9%. RAP Savings ($ millions). 43.6M. 41.7M.
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Recycled Asphalt Program & Environmental Stewardship Program (Post Consumer Content) Robert C. Rea Nebraska Department of Roads WASHTO – Omaha, Nebraska April 2014
Average RAP Contents (Overall) 39.2% 37.3% 34.4% 28.6% 27.3% 6.9%
RAP Savings ($ millions) 43.6M 41.7M 35.3M 23.3M 19.8M 3.6M
How did we get to 39.2% average RAP ? • Design and Specifications to optimize RAP • RAP Incentive for binder savings
RAP Incentive for binder savings • 1. Binder Cost Subsidiary to Mix (36 States) • Not Needed -- Incentive is already there to use less contractor purchased ‘new’ binder • SPECIFICATIONS • 2. Binder Paid Separately as Bid Item (14 States) • Needed -- No incentive for the Contractor to underrun an established item, so we must place incentive on the net binder savings • SPECIFICATIONS and INCENTIVE
DOT Millings from ‘ON’ project DOT Millings from ‘OFF’ project Contractor ‘Owned’ Millings 15% of Binder Savings For Contractor 35% of Binder Savings For Contractor 50% of Binder Savings For Contractor 65/35 Incentive Split 85/15 Incentive Split 50/50 Incentive Split 90% of our projects are this 8% of our projects are this 2% of our projects are this
Example 40,000 Ton Project ( 5 M ESAL Design – Typical SPR mix ) MILLINGS FROM ON PROJECT 85/15 Incentive Split • Mill 2” – Fill 3” • Hot Mix = $ 30 per ton • Binder PG 64-34 = $650 per liquid ton • Design is for 5.4% Binder Content
Virgin Mix (No RAP) • Hot Mix = 1,200,000 • Virgin Binder = $1,404,000 • Binder from RAP = $0 • Total Cost = $2,604,000 Total Cost = $2,604,000 Recycle Savings to DOT = $0.00 Recycle Incentive to the Contractor = $0.00 Total final Cost Realized by DOT $2,604,000 • Pre-incentive 2008 (6.9% RAP) • Hot Mix = 1,200,000 • Virgin Binder = $1,307,124 • Binder from RAP = $96,876 • Total Cost = $2,507,124 Total Cost = $2,604,000 Recycle Savings to DOT = $96,876 Recycle Incentive to the Contractor = $0.00 Total final Cost Realized by DOT $2,507,124 • Current w/Incentive (45% RAP) • Hot Mix = 1,200,000 • Virgin Binder = $772,200 • Binder from RAP = $631,800 • Total Cost = $1,972,200 Total Cost = $2,604,000 Recycle Savings to DOT = $537,030 Recycle Incentive to the Contractor = $94,770 Total final Cost Realized by DOT $2,066,970
Virgin Mix (No RAP) Total final Cost Realized by DOT $2,604,000 Pre-incentive 2008 (6.9% RAP) Savings from optimizing RAP $440,000 to $550,000 Total final Cost Realized by DOT $2,507,124 Current w/Incentive (45% RAP) Total final Cost Realized by DOT $2,066,970 On one 40,000 ton hot mix project
REASONS RAP USE MAY BE LIMITED • Agency limits use of RAP or says ‘I want the new stuff, not the used stuff ’ • Stigma of lesser quality, Engineered Design a must • Plant Superintendant says ‘The plant won’t run that much’ • Design must optimize mill and fill strategies or ‘Road Mining’ • Requires binder grade bumps/dumps when higher amounts are used • Restrictive in the specification, i.e. dust/asphalt maximum • Limits the RAP #200 amounts and therefor rejects the RAP • Voids and VMA and other properties restrict the amount of RAP
SPR – Mix Design • CAA • 83 Allows for RAP Variation, typically 90+ • FAA • Allows for RAP Variation, typically 44+ • FAA Sp. Gravity slightly lowers true FAA • Binder Grade and Volumetrics provide added Rutting Resistance • Overshoot FAA – Increased Cracking • Voids • Allow more dust & binder, better field density • Min. Binder • Used as Factor for VMA • #200 • Typically around 4-6%, D/B around 1.0-1.2
APA Testing of SPR Mixes • 8000 Cycles • 100 PSI Pressure Load • 64 degrees C • Max of 12 mm Rutting
Approach to a 50% RAP Project • Pick a 20,000 to 40,000 Ton Project • Use a ‘tried and true’ mix that you know works and has been a workhorse for your state • Specify the quality and type of virgin aggregate that you want to use, in other words, the ones that you like and are of good quality • Use softest base oil you can get either -34 or -28 if you can • Specify a minimum Binder Content if you don’t pay ac separately • Specify minimum 40 % RAP • Have the RAP come from the road…….fresh processed millings • Be flexible with the #200 material • Lower voids and no VMA spec, effects of burnoff oven – another all day presentation to discuss this control by voids and binder content • Place it in all lifts, especially surface, we want to monitor this material
Robert C. Rea 402 479 3839 office 402 326 9934 mobile robert.rea@nebraska.gov
Type ‘R’ Asphalt $ 12 - $ 20 $ 44 $ 36 $ 24
RAP Savings Potential • $ 12 to $20 per Ton • x ?? Million Tons • $ 10 to 40 Million • Annual Savings realized every year, over and over and over again . • Not to mention, Better on the environment, Green Technology, Recycling, Less Raw Materials, Less Hauling, Less Transportation and consumption of fuels ……..