环氧沥青钢桥面讲座

1、ChemCo SystemsDurable pavement for Steel DecksChemCo Systems Historyplate 1950sShell Oil develops jet fuel and hydraulic oil resistant paving for airport taxiways. p1966 Caltrans uses Epoxy Asphalt on San Mateo-Hayward Bridge (in use). p1976 Bay Bridge 18mm overlay on lightweight concrete (in use).p

2、1984 Golden Gate Bridge redecked (in use). p2000 2nd Nanjing (first Asia project). -5th generation product used for the first timeChemCo SystemsApplicationspOrthotropic steel decks New construction Replacement paving Re-deckingpOverlayspTemporary chip sealsFor replacement deck panelspHigh (heavy wei

3、ght) traffic, strategic roads with long life requirementpFuel and chemical resistant pavingLionsgate BrChemCo SystemsEA ChemistrypEpoxy cross-linked polymer: continuous phase, asphalt: discontinuous phasep2 component binder and 2 component bond coat Part A Resin Part B Asphalts and cross-linkerspAmb

4、ient temperature reactive cure mechanismpCured polymer is thermoset (wont melt)ChemCo SystemsPropertiespExtremely high fatigue resistancepHigh strength bond coat Protects against delamination Ensures composite action with steel Resists high summer deck temperaturespThermoset Will not meltpHigher mod

5、ulus than other flexible pavements Reduces deck deflectionElement meshing“Epoxy Asphalt has a fatigue life of 2 to 3 orders of magnitude greater than the PG76-22 I-5 mix”.-Rutgers University study ChemCo SystemsPropertiespDoes not oxidize (like all other asphalts) No embrittlement upon agingpLow voi

6、ds (typically 2 %) Water impermeable No chloride ion penetration No corrosion-no membrane requiredHigh Temperature bond performanceFHWA OECD Long Lived Pavement StudyTurner Fairbanks Highway Research CenterChemCo SystemsFundamental differencepHMA Asphalt, SMA, Gussasphalt, PMA are thermoplastics: wi

7、ll meltpEpoxy Asphalt is thermoset: will not melt“Epoxy Asphalt concrete has shown excellent performance including anti-cracking feature under low temperature, stability under high temperatures and oil-corrosion resistance.”-W. Wang, Changan University ChemCo SystemsAdvantagespLow permeability preve

8、nts deck corrosion pFatigue resistance minimizes cracksp4+ times more stability than standard ACpHandles truck wheel overloads (common in Asia)-Rutgers Univ.ChemCo SystemsAdvantagespNo rutting or shovingpUse standard AC paving equipment Very high bond strength Paving placement is fastpWont delaminat

9、e“The superior oxidation resistance of the epoxy asphalt material was even more obvious in the Cantabro tests”-Transit New ZealandOECD report ChemCo SystemsTypical new construction detailChemCo SystemsEA SpecificationsDense graded mix, ” (12mm) minus Basalt rock for skid resistance and long wearpLow

10、 temperature paving (110-121C) Time/temp monitoring is critical QC element Similar temps to warm mixpLab simulation (fatigue testing) advised for unique decksChemCo SystemsO-T Deck Pavement Stressfrom wheel load deflectionLongitudinal stiffenerTENSIONTENSIONChemCo SystemsFatigue testingevaluate pave

11、ment design on project specific deckpKeys Realistic paving composite specimens Good tests take time Research performance of local materials (aggregates) Use environmental chamber to control extreme tempsChemCo SystemsComparison: EA vs. polymer modified AC or SMAPropertiesConditionEpoxy AsphaltPolyme

12、r ACHigh temperaturesWill not meltMeltsPermeabilityNonemeasurableChanges with agea. Will not oxidizeb. Flexibility constantNo age related performance lossesOxidizesFlexibility declinesDelamination potentialVery lowConsistent composite behaviorHighFuel resistanceHighLowwill soften and dissolve binder

13、Rutting, shovingStableUnstable under high temps and loadsChemCo SystemsChinese standard deck detailFatigue test specimenwith 3 pt. dynamic loadon 300 mm centerp300 mm stiffener spacingp12 mm deck plate (prior to 1999)p14 mm deck plate (after 1999)p50-55 mm EA pavingpLocus of highest stress is over s

14、tiffeners, particularly in truck lanespDynamic fatigue test is good predictorChemCo SystemsAsian conditionspHigh deck temps To 90 CpExtreme temperature cycle between winter and summerpConstruction QC varies widelypStandardized deck design in mainlandChemCo SystemsAsian conditionspConsistent very hig

15、h truck wheel overloads To 120 MT on 18 wheelers SMA and gussasphalt sometimes fail as quickly as 2-3 yrs. SuTong Br.ChemCo SystemsEA: DisadvantagespTime and temperature controls criticalControls can lead to higher quality and uniformityPaving plant needs to be within 45-50 minute drive pToo complic

16、atedOver 35 bridges in Asia in past 10 yrs successfully completed including 1st suspension bridge in Viet NamChemCo provides advisorsUse test section in convenient location to train local paving crews before deck placementpCosts moreCost difference dwarfed by frequent closures and repavingThuan Phuo

17、c BridgeDaNang, Viet NamChemCo SystemsNext in N. AmericaFremont, Portland 2011Repave in JulyMacDonald, Nova Scotia 2015Redeck similar to LionsgateSan Francisco-Oakland Bay 2012Single anchored suspension (new East Span)ChemCo SystemsFuturepReduce pavement weightpLocal manufacturingpOECD-ECMT Joint Tr

18、ansport Research on long life pavements (U.S., U.K., France, Germany, Denmark, New Zealand, Australia) Open graded performance benefits demonstratedpImprove fatigue performance in most challenging applications Decks with extremely high wheel overloads Decks with thin plates (12 mm) Hottest tropical environmentsChemCo SystemsConclusionspDesign, test and confirm for we