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Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Durable pavement for Steel Decks
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
History
late 1950s Shell Oil develops jet fuel and hydraulic oil resistant paving for airport taxiways.
1966 Caltrans uses Epoxy Asphalt on San Mateo-Hayward Bridge (in use).
1976 Bay Bridge 18mm overlay on lightweight
concrete (in use).
1984 Golden Gate Bridge redecked (in use).
2000 2nd Nanjing (first Asia project). --5th generation product used for the first time
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Applications
Orthotropic steel decks• New construction• Replacement paving• Re-decking
Overlays Temporary chip seals
• For replacement deck panels
High (heavy weight) traffic, strategic roads with long life requirement
Fuel and chemical resistant paving
Lionsgate Br
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
EA Chemistry
Epoxy cross-linked polymer: continuous phase, asphalt: discontinuous phase
2 component binder and 2 component bond coat• Part A Resin• Part B Asphalts and cross-linkers
Ambient temperature reactive cure mechanism
Cured polymer is thermoset (won’t melt)
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Properties Extremely high fatigue
resistance High strength bond coat
• Protects against delamination
• Ensures composite action with steel
• Resists high summer deck temperatures
Thermoset• Will not melt
Higher modulus than other flexible pavements• Reduces deck deflection
Element 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
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Properties
Does not oxidize (like all other asphalts)
• No embrittlement upon aging
Low voids (typically ~2 %)• Water impermeable• No chloride ion
penetration• No corrosion--no
membrane required High Temperature bond performance
FHWA OECD Long Lived Pavement Study
Turner Fairbanks Highway Research Center
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Fundamental difference
HMA Asphalt, SMA, Gussasphalt, PMA are thermoplastics: will melt
Epoxy 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, Chang’an University
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Advantages
Low permeability prevents deck corrosion
Fatigue resistance minimizes cracks
4+ times more stability than standard AC
Handles truck wheel overloads (common in Asia)
--Rutgers Univ.
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Advantages
No rutting or shoving Use standard AC
paving equipment• Very high bond
strength• Paving placement
is fast Won’t delaminate
“The superior oxidation resistance of the epoxy asphalt
material was even more obvious in the Cantabro tests…”
--Transit New Zealand—OECD report
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Typical new construction detail
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
EA Specifications
Dense graded mix, ½” (12mm) minus• Basalt rock for skid
resistance and long wear Low temperature paving (110-
121ºC)• Time/temp monitoring is
critical QC element • Similar temps to warm mix
Lab simulation (fatigue testing) advised for unique decks
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
O-T Deck Pavement Stressfrom wheel load deflection
Longitudinal stiffener
TENSION
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Fatigue testingevaluate pavement design
on project specific deck
Keys• Realistic paving
composite specimens
• Good tests take time
• Research performance of local materials (aggregates)
• Use environmental chamber to control extreme temps
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Comparison: EA vs. polymer modified AC or SMA
Properties
Condition Epoxy Asphalt Polymer AC
High temperatures Will not melt Melts
Permeability None measurable
Changes with age a. Will not oxidizeb. Flexibility constant
No age related performance losses
a. Oxidizesb. Flexibility
declines
Delamination potential Very lowConsistent composite
behavior
High
Fuel resistance High Low—will soften and dissolve binder
Rutting, shoving Stable Unstable under high temps and loads
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Chinese standard deck detail
Fatigue test specimen
with 3 pt. dynamic load
on 300 mm center
300 mm stiffener spacing12 mm deck plate (prior to 1999)14 mm deck plate (after 1999)
50-55 mm EA pavingLocus of highest stress is over stiffeners, particularly in truck lanesDynamic fatigue test is good predictor
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Asian conditions High deck temps
• To 90 °C Extreme temperature cycle
between winter and summer Construction QC varies
widely Standardized deck design in
mainland
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Asian conditions
Consistent very high truck wheel overloads• To 120 MT on 18
wheelers
• SMA and gussasphalt sometimes fail as quickly as 2-3 yrs.
SuTong Br.
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
EA: Disadvantages
Time and temperature controls critical• Controls can lead to higher quality and uniformity• Paving plant needs to be within 45-50 minute drive
Too complicated• Over 35 bridges in Asia in past 10 yrs successfully
completed– including 1st suspension bridge in Viet Nam
• ChemCo provides advisors• Use test section in convenient location to train local paving
crews before deck placement
Costs more• Cost difference dwarfed by frequent closures and repaving
Thuan Phuoc Bridge
DaNang, Viet Nam
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Next in N. America
Fremont, Portland 2011• Repave in July
MacDonald, Nova Scotia ~2015
• Redeck similar to Lionsgate
San Francisco-Oakland Bay ~2012• Single anchored suspension
(new East Span)
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Future
Reduce pavement weight
Local manufacturing OECD-ECMT Joint
Transport Research on long life pavements• (U.S., U.K., France,
Germany, Denmark, New Zealand, Australia)
• Open graded performance benefits demonstrated
Improve fatigue performance in most challenging applications• Decks with
extremely high wheel overloads
• Decks with thin plates (12 mm)
• Hottest tropical environments
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Conclusions
Design, test and confirm for wear course successEpoxy Asphalt, a thermoset material, performs on challenging decksEpoxy Asphalt offers life cycle cost benefits
Asian lessons learned• Over design
surfacing when realistic data not available
• Be flexible to adopt local improvements
Epoxy AsphaltEpoxy Asphalt
ChemCo Systems
Thanks for your interest!