Asphalt Materials: Basics of RAP, Usage and Specifications

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2 Asphalt Materials: Basics of RAP, Usage and Specifications 36 th Annual Rocky Mountain Asphalt Conference and Equipment Show February 19, 2009 Denver, Colorado

3 By Tom Blair Director of Product Engineering Asphalt Group Schmidt Construction/ Edw. C. Levy Co West 12 Mile Rd. Wixom, MI (248)

4 About the Edw. C. Levy Co.

5 LEVY IS ONE OF THE LARGEST RECYCLERS IN THE UNITED STATES, AUSTRALIA, AND THAILAND WE HAVE BEEN RECYCLING SINCE WE PROCESS MILLIONS OF TONS OF SLAG IN THE U.S. PER YEAR THAT IS SOLD AS CONSTRUCTION MATERIALS. WE ALSO RECOVER MORE THAN A MILLION TONS OF METALLICS PER YEAR THAT ARE RECYCLED BACK INTO THE STEEL MAKING PROCESS. WE PROCESS AND UTILIZE NEARLY A HALF A MILLION TONS OF RECYCLED ASPHALT PAVEMENT (RAP) PER YEAR IN OUR ASPHALT MIXES AND HAVE BEEN USING RAP SINCE 1975.

6 Edw. C. Levy Co. U.S.A. Asphalt Production & Paving Operations in 11 States Sand & Gravel Operations Quarry Operations Steel Mill Services Trucking Aggregate Docks Sand, Gravel, Limestone, S.F. Slag, B.F. Slag Ready Mix Concrete

7 Asphalt Production & Paving

8 Colorado Asphalt Production & Paving Quarry Operations Sand & Gravel Operations Trucking

9 DELTA YARD COLORADO SPRINGS

10 RAP Usage and Specifications

11 WHO SHOULD RECYCLE ASPHALT PAVEMENTS?

12 ANYONE WHO WANTS TO SAVE MONEY AND HELP THE ENVIRONMENT

13 RAP IS THE NATIONS TOP RECYCLED MATERIAL

14 WHY SHOULD WE RECYCLE ASPHALT PAVEMENTS?

15 ENVIRONMENTALLY FRIENDLY CONSERVE NATURAL RESOURCES AND ENERGY SAVE MONEY STRETCH THE HIGHWAY DOLLARS FURTHER WITH LOWER BID PRICES BECAUSE WE CAN DESIGN AND BUILD AS GOOD OR BETTER PAVEMENTS WITH RAP THAN WITH ALL NEW MATERIALS

16 NEWER ASPHALT PLANTS ARE DESIGNED TO BLEND RAP UNIFORMLY WITHOUT ADVERSE ENVIRONMENTAL EFFECTS. BETTER SPECIFICATIONS MEASURE PERFORMANCE RELATED PROPERTIES. SMARTER PEOPLE ON BOTH SIDES AGENCIES AND CONTRACTORS. MORE QUALITY CONTROL AND QUALITY ASSURANCE TESTING.

17 COST EFFECTIVE RECYCLING ASPHALT BACK INTO ASPHALT MIXTURES IS ACTUALLY LESS EXPENSIVE THAN MAKING MIX WITH ALL NEW MATERIALS. LOTS OF OTHER MATERIALS ARE MORE EXPENSIVE TO USE THAN USING ALL NEW MATERIALS. MANY REQUIRE SUBSIDIES BEFORE THEY ARE USED AND MANY RESULT IN LOWER QUALITY FINISHED PRODUCTS THAN ALL NEW.

18 RAP Value per Ton Aggregate Value $9.00x0.955= $8.60 Asphalt Cement Value $360.00x0.045= $16.20 Total RAP Value per Ton = $24.80 Less Crushing and Handling Costs -$5.00 Remaining Value per Ton = $19.80 Mix Cost Savings 10% in Mix = $1.98/per mix ton 20% in Mix = $3.96/per mix ton 25% in Mix = $4.95/per mix ton

19 RAP Value per Ton Aggregate Value $9.00x0.955= $8.60 Asphalt Cement Value $360.00x0.045= $16.20 Total RAP Value per Ton = $24.80 Less Crushing and Handling Costs -$5.00 Remaining Value per Ton = $19.80 Less Agency Ownership Replacement Cost for Use on Shoulders -$10.00 Remaining Value per Ton = $9.80

20 WHERE SHOULD WE RECYCLE ASPHALT PAVEMENTS?

21 INTO ANY PAVEMENT THAT WE CAN DESIGN AND ENGINEER IT TO PERFORM AS GOOD OR BETTER THAN IT WOULD WITHOUT RAP

22 WHEN SHOULD WE RECYCLE ASPHALT PAVEMENTS?

23 RIGHT NOW BEFORE WE RUN OUT OF GOOD AGGREGATES OR MONEY

24 A BRIEF HISTORY OF USING RAP 1970 s EXPERIMENTAL JOBS FROM 70% UP TO 100% RAP ANY WAY WE COULD. NO MIX DESIGNS DUMP AND RUN. LOTS OF FAILURES 1980 s CUT HOLES IN PLANTS AND HAD ENVIRONMENTAL ISSUES. LOTS OF STATES USED UP TO 50% RAP. LITTLE OR NO QUALITY CONTROL TESTING. NO VOLUMETRIC AND VERY LITTLE ACCEPTANCE TESTING. MANY MORE FAILURES. THEN RAP COLLARS INVENTED TO PROVIDE A BETTER WAY TO INTRODUCE RAP INTO THE PLANT 1990 s BETTER PLANT DESIGNS FOR INTRODUCING RAP INTO THE PLANT. THEN COUNTERFLOW PLANTS DESIGNED TO USE HIGH PERCENTAGES OF RAP. VOLUMETRIC TESTING INTRODUCED. LOTS OF QUALITY CONTROL TESTING FOR VOIDS ACCEPTANCE JOBS. MORE QUALITY ASSURANCE TESTING. GOOD RAP MIX PERFORMANCE

25 A BRIEF HISTORY OF USING RAP (cont.) LATE 1990 s TO THE PRESENT EVEN BETTER ASPHALT PLANTS DESIGNED TO RUN HIGHER RAP PERCENTAGES YET BE EVEN MORE ENVIRONMENTALLY FRIENDLY. MORE EMPHASIS ON QUALITY CONTROL. TIGHTER ACCEPTANCE SPECIFICATIONS LIKE PWL. SUPERPAVE INTRODUCED. LOTS OF NEW RESEARCH ON MIXTURE PERFORMANCE AND RAP USE. EXCELLENT RAP MIX PERFORMANCE REMEMBER WHEN WE FIRST STARTED RECYCLING PAPER AND PLASTIC? THEY USED TOO HIGH OF A RECYCLED MATERIAL CONTENT AND THE PERFORMANCE WAS POOR. NOW THEY USE LESS RECYCLED MATERIAL CONTENT BUT PUT IT IN ALMOST EVERYTHING AND NO ONE KNOWS THE DIFFERENCE. SAME THING WITH AN ALUMINUM CAN OR YOUR NEW CAR. RAP ASPHALT MIXES CAN PERFORM BETTER THAN ALL NEW MATERIAL IF DONE CORRECTLY

26 THREE MAIN RULES FOR SUCCESSFUL RECYCLING OF ASPHALT PAVEMENTS

27 1. THE QUALITY OF THE PRODUCT MADE WITH RECYCLED MATERIALS MUST BE EQUAL TO OR BETTER THAN THE QUALITY OF THE ORIGINAL PRODUCT. AS GOOD OR BETTER DON T USE TOO HIGH OF A RECYCLED MATERIAL CONTENT.

28 2. THE RECYCLED PRODUCT PRODUCED MUST BE COST EFFECTIVE. SOME DAY IT MAY BE ABLE TO COST MORE WHEN WE GET CREDIT FOR USING RECYCLED MATERIALS. THE GREAT THING ABOUT USING RECYCLED ASPHALT PAVEMENT (RAP) IS THAT IT LOWERS THE COST OF THE FINISHED PRODUCT AND CAN PROVIDE AS GOOD OR BETTER FINISHED PRODUCT THAN USING ALL NEW MATERIALS IF DESIGNED PROPERLY.

29 3. WE MAY NEED TO CHANGE SOME OF THE OTHER RAW MATERIALS WE USE WITH THE RECYCLED MATERIAL AND SOME OF OUR PROCESSES TO MEET THE FIRST TWO RULES. DON T JUST SUBSTITUTE IN A RECYCLED MATERIAL WITHOUT DESIGNING FOR IT MOST OF THE TIME WHEN USING RAP WE NEED TO USE CLEANER AGGREGATES

30 SO - HOW CAN WE DESIGN AND ENGINEER THE PAVEMENT TO PERFORM AS GOOD OR BETTER THAN IT WOULD WITHOUT RAP?

31 KEEP THE MIX SPECIFICATIONS THE SAME AS THEY WOULD BE WITHOUT RAP KEEP IT CLEAN KEEP IT SMALL KEEP IT CONSISTENT KEEP IT HOT KEEP IT TESTED KEEP IT PERFORMING

32 KEEP THE MIX SPECIFICATIONS THE SAME DESIGN THE MIX WITH THE SAME AIR VOIDS, VMA, VFA, AC/FINES RATIO AS VIRGIN MIX DON T JUST SUBSTITUTE RAP INTO THE MIX WITHOUT A NEW MIX DESIGN!!! EVALUATE THE AGGREGATE PROPERTIES OF THE RAP AGGREGATE AND USE CLEANER BETTER QUALITY AGGREGATES TO MEET THE MIX DESIGN CRITERIA IF NECESSARY DO NOT USE WIDER TOLERANCES FOR ACCEPTANCE TESTING - USE VOIDS ACCEPTANCE

33 SPECIFICATIONS FOR THE RAP TESTING REQUIREMENTS AT ACCEPTABLE FREQUENCIES ON IMPORTANT PARAMETERS UNIFORMITY TOLERANCE LIMITS QUALITY CONTROL PLAN TO ADDRESS RAW MATERIAL HANDLING, CRUSHING AND SCREENING, STOCKPILING, SAMPLING AND TESTING, AND RAP MIX PRODUCTION MONITORING MAXIMUM PARTICLE SIZE

34 RAP MIX DESIGN HINTS START WITH THE RAP AND DESIGN AROUND IT. USE CLEANER AGGREGATES IF NECESSARY TO MEET ALL THE SAME CRITERIA AS FOR VIRGIN MIXES. MAKE SURE YOU KNOW ALL THE PROPERTIES OF THE RAP; AC CONTENT/STIFFNESS, GRADATION, SPECIFIC GRAVITY AND ABSORPTION, DELETERIOUS, PARTICLE SHAPE, AND ANGULARITY. WATCH WHAT GRADE OF VIRGIN BINDER YOU SELECT. BUMPING THE TOP AND BOTTOM IS OFTEN TIMES TOO SOFT AND CAN RESULT IN SOFT MIXES. NEW RESEARCH SHOWS CHANGING GRADES OF VIRGIN ASPHALT IN RAP MIXES MAY NOT BE NECESSARY.

35 KEEP IT CLEAN DO NOT ALLOW ANYTHING OTHER THAN BROKEN ASPHALT, RETURNED ASPHALT, CLEAN- OUT ASPHALT, OR MILLINGS IN THE RAP RAW MATERIAL PILE. HAVE SIGNS MADE UP THAT SAY WE ACCEPT CLEAN BROKEN ASPHALT ONLY. VIOLATERS WILL LOSE DUMPING PRIVILEGES CHECK TRUCKS DUMPING MATERIAL IN YOUR RAW MATERIAL PILE FOR CONTAMINATION AND REJECT THEM

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41 KEEP IT CLEAN (cont.) MAKE SURE THE RAP CRUSHER IS CLEANING DEBRIS OFF HIS SCREEN REGULARLY TO KEEP IT OUT OF THE FINISHED PRODUCT PILE. A GOOD RAP CRUSHER IS YOUR MOST VALUABLE RESOURCE IF HE BLENDS THE RAW MATERIAL AND FINISHED PRODUCT PILES UNIFORMLY AND KEEPS THE BAD MATERIAL AND JUNK OUT. THIS MATERIAL LIKE TOPSOIL, CLAY, TIRES, CONCRETE, BRICKS, AND WOOD MUST BE HAULED TO THE LANDFILL. DON T GET CHEAP WITH THE RAP CRUSHER. WE ARE ALWAYS TRING TO SAVE A NICKEL AND THIS WILL TRANSLATE INTO THE TYPE OF SERVICE HE GIVES YOU.

42 KEEP IT SMALL PICK THE RIGHT SIZE TO CRUSH RAP AT - BALANCING COST WITH HOW MANY MIXES IT CAN BE UTILIZED IN. SMALLER SIZES CAN HAVE LESS VARIABILITY, LESS SEGREGATION, AND TRANSFER HEAT BETTER. SMALLER SIZES SCREEN OUT MORE DEBRIS DURING CRUSHING. SMALLER SIZES OF SCALPER SCREENS ALLOW BETTER HEAT TRANSFER, DRYING, AND MIXING OF THE RAP WITH THE AGGREGATE AND AC.

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45 KEEP IT CONSISTENT SPREAD OUT PLANT CLEAN OUT MATERIAL, WASTED SILO MATERIAL, AND RETURNED MATERIAL SO THAT IT DOESN T HARDEN INTO BIG CHUCKS. THIS MAKES IT HARD TO CRUSH AND CAN CAUSE POCKETS OF HIGH ASPHALT CONTENT FINISHED PRODUCT BUILD THE RAW MATERIAL PILE IN LAYERS AND SPREAD OUT MILLINGS SO THAT THE PILE WILL BE UNIFORM IN MATERIAL TYPE WHEN CRUSHED WORK A LARGE LOADING FACE OF THE RAW MATERIAL PILE TO FEED THE CRUSHER

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47 NOT TOO CONSISTENT

48 NICE RAW MATERIAL PILE

49 KEEP IT CONSISTENT (cont.) BLEND THE RAW MATERIAL PILE WHILE FEEDING THE CRUSHER. MOVE POCKETS OF MILLINGS OR CLEAN-OUT MATERIAL OUT OF THE WAY IF NECESSARY TO HELP KEEP CONSISTENCY OF THE FINISHED PRODUCT. MAKE SURE SOMEONE TAKES SAMPLES OF THE FINISHED PRODUCT DURING CRUSHING FOR TESTING AT SET INTERVALS. ALSO, TAKE SOME RANDOM SAMPLES TO COMPARE RESULTS. BUILD THE FINISHED PRODUCT PILE IN LAYERS. USE A DOZER OR A PROGRAMABLE STACKER

50 KEEP IT CONSISTENT (cont.) IF POSSIBLE, AVOID DOUBLE HANDLING THE FINISHED PRODUCT TO PREVENT SEGREGATION USE AS BIG OF A LOADING FACE AS POSSIBLE ON THE FINISHED PRODUCT PILE TO FEED THE RAP BIN LOAD OUT PERPENDICULAR TO THE DIRECTION THE STOCKPILE WAS BUILT IN

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52 KEEP IT HOT MAKE THE AGGREGATE HOT ENOUGH IN THE PLANT FOR GOOD DRYING AND HEAT TRANSFER TO OCCUR DON T RUN THE PLANT TOO FAST MONITOR MOISTURE CONTENTS OF THE RAP OFTEN AND UPDATE PLANT CONTROLS IF USING STIFFER ASPHALT CEMENTS, MAKE THE MIX HOTTER WHEN IT IS WET OR COLD USE LESS RAP

53 KEEP IT TESTED TEST THE RAP DURING CRUSHING ONCE EVERY 1000 TONS OR MORE AS IT IS BEING PRODUCED VERIFY PRODUCTION TEST RESULTS LATER WITH LOADING FACE SAMPLES DURING USE GIVE FEEDBACK TO RAP CRUSHER DURING CRUSHING IF CONSISTENCY IS NOT BEING MET TEST AND ADJUST THE VOLUMETRIC PROPERTIES OF THE MIX OFTEN TO ENSURE QUALITY ADD A LITTLE EXTRA ASPHALT CEMENT TO ACCOUNT FOR ABSORPTION IF THE MIX WILL BE STORED FOR AN EXTENDED PERIOD

54 KEEP IT TESTED (cont.) WATCH OUT IF USING THE IGNITION FURNACE FOR AC CONTENTS OF THE RAP. IT IS BEST TO VERIFY THE RESULTS ONCE IN A WHILE WITH SPLIT SAMPLE TESTING USING A SOLVENT EXTRACTION WITH A GOOD SOLVENT. TO BE SUCCESSFUL, YOU PROBABLY WILL NEED INCREASED TESTING CAPABILITY FOR RUNNING RAP MIXES BECAUSE THEY CAN TAKE A LITTLE EXTRA WORK.

55 TO KEEP IT PERFORMING MAKE SURE YOU ACCOUNT FOR THE RAP AGGREGATE AND BINDER PROPERTIES IN THE MIX DESIGN STAGE. DON T BE AFRAID TO ADJUST THE MIX PROPERTIES DURING PRODUCTION TO KEEP THE BOAT IN THE MIDDLE OF THE CANAL. CONTROL THE VARIABILITY IN ALL PHASES OF THE PROCESS. TREAT THE RAP LIKE IT IS WORTH TWO TO FOUR TIMES AS MUCH AS ONE OF YOUR AGGREGATE STOCKPILES. IT IS!

56 TO KEEP IT PERFORMING (cont.) BECAUSE OF THE STIFFER ASPHALT BINDERS IN THE RAP, IT CAN ACT AS AN ASPHALT MODIFIER AND INCREASE RUTTING RESISTANCE IF USED CORRECTLY. ALSO RAP MIXES USUALLY HAVE BETTER RESISTANCE TO MOISTURE DAMAGE. CALIBRATE THE RAP FEEDER OFTEN. WATCH THE PERFORMANCE OF THE RAP FEEDER AND PREVENT BRIDGING OR FLOW PROBLEMS WITH THE FEEDER. LINE THE BINS. DON T BUILD THE RAP FINISHED PRODUCT STOCKPILES TOO HIGH.

57 HOW CAN WE DESIGN AND ENGINEER THE PAVEMENT TO PERFORM AS GOOD OR BETTER THAN IT WOULD WITHOUT RAP?

58 KEEP THE MIX SPECIFICATIONS THE SAME AS THEY WOULD BE WITHOUT RAP KEEP IT CLEAN KEEP IT SMALL KEEP IT CONSISTENT KEEP IT HOT KEEP IT TESTED KEEP IT PERFORMING

59 SUMMARY GOOD CRUSHED, BLENDED, CLEAN RAP PILE GOOD PLANT, OPERATED PROPERLY MIX THOROUGHLY TO GET IT DRY, HOT, AND CONSISTENT GOOD MIX DESIGN MEET ALL PROPERTIES GOOD QUALITY CONTROL CONTROL VOLUMETRIC PROPERTIES. DON T JUST WATCH IF NECESSARY, ADD A LITTLE AC IF STORING THE MIX OVERNIGHT OR FOR LONG PERIODS TO ACCOUNT FOR ABSORPTION AND DON T FORGET TO KEEP IT HOT IN THE SILOS

60 LET S KEEP RAP THE NATIONS TOP RECYCLED MATERIAL

61 THANK YOU!

62 QUESTIONS?