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Warm Mix Technology to Improve Compaction Larry Michael 2005 NEAUPG Annual Meeting Burlington Vt.
Warm Mix Technologyto
Improve Compaction
Larry Michael
2005 NEAUPG Annual MeetingBurlington Vt.
Warm Mix Technology• Reduce Mixing and Compaction
Temperature• Reduce Fumes• Reduce Fuel Costs• Improve Workability• Improve Density• Extend Paving Window• Improve Quality
CONCERNS:
• Costs• Process• Binder Storage Tanks• PG Binder Grade• Long Term Performance• DOT Acceptance• There’s No Smoke
Available WMAAvailable WMATechnologiesTechnologies
Processes include:Processes include:
–– WAM Foam – Shell/WAM Foam – Shell/KoloKolo VeidekkeVeidekke–– Zeolite – Eurovia/Hubbard ConstructionZeolite – Eurovia/Hubbard Construction–– SasobitSasobit – – SasolSasol Int./Moore and Int./Moore and MungerMunger–– Evotherm Evotherm - - MeadWestvacoMeadWestvaco–– New processesNew processes
Sasobit®• Product of
– Sasol Wax GmbH (Germany)• Fischer-Tropsch parrafin wax
– Fine crystalline long chain aliphatichydrocarbon
– Produced from coal gasification• Available in
– Flakes or powdered form– 2, 5, 20, and 600 kg bags
Sasobit®• Fischer-Tropsch waxes
– Different than naturally occurring asphaltwaxes in structure and physical properties
– Higher melting point– Lower penetration– Higher viscosity– Higher molecular weight
Asphalt Case Studies presented at NAPA Convention Feb 17, 2005
Frankfurt AirportFrankfurt Airport• Asphalt mixture laid at low temperature• Better compactability• Increased resistance to deformation at
high temperatures
Asphalt Case Studies presented at NAPA Convention Feb 17, 2005
Frankfurt AirportFrankfurt Airport• Bear heaviest aircraft in 2-3 hours• Reduced cooling, key to 300-step project
Will Sasobit have a
negative effect on mix
quality?
QUESTION…
NCAT Evaluation
• Improved compact ability to 1900F• Did not affect resilient modulus• Did not increase rutting potential (APA)• Cure time to open to traffic is not an issue• Moisture damage with lower temperature
may be an issue• Anti-aging Properties
TSRST
-30.0
-27.5
-25.0
Cra
ckin
g Te
mpe
ratu
re (°
C)
Unmodified Memons Sasobit 3%
Replicate 1Replicate 2Replicate 3Average
XXXXXXXXXX
Field Trials
1. 45% RAP 19mm Base2. SMA 19.0mm Intermediate Base3. 35% RAP 9.5mm Surface Mix
Added – 1.5% Sasobit by weight of total binder
45 % Rap45 % Rap
340 F
Performance Evaluation of High RAP Base Mixture Containing Sasobit
Maryland State Highway Administration
Advanced Asphalt Technologies, LLC108 Powers Court, Suite 100
Sterling, VA 20166-9321(703) 444-4200
August 19, 2005
ADVANCED ASPHALT TECHNOLOGIESENGINEERING SERVICES FOR THE ASPHALT INDUSTRY
1
10
100
1000
10000
1.E-06 1.E-05 1.E-04 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06
Reduced Frequency, Hz
E*, k
si
Plant Aged Control
Plant Aged SASOBIT
-3
-2
-1
0
1
2
3
0 10 20 30 40 50Temperature, C
Log
Shift
Fac
tor
Mixture Dynamic Modulus Master Curves for Plant Aged Conditions
1
10
100
1000
10000
1.E-06 1.E-05 1.E-04 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06Reduced Frequency, Hz
E*, k
si
LTOA Control
LTOA SASOBIT
-3
-2
-1
0
1
2
3
0 10 20 30 40 50
Temperature, C
Log
Shift
Fac
tor
Mixture Dynamic modulus Master Curves for Long-Term Oven Aged Conditions
0.8
1.0
1.2
1.4
1.6
1.8
2.0
1.E-06 1.E-05 1.E-04 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01Reduced Frequency, Hz
Plan
t Age
d E*
/ LT
OA
E*
Control
Sasobit
Effect of Simulated Long-Term Aging
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Number of Loads
Per
man
ent A
xial
Stra
in, %
Control 1
Control 2
Control 3
SASOBIT 1
SASOBIT 2
SASOBIT 3
Repeated Load Permanent Deformation Response for Control and Sasobit® Mixtures
0100200
300400500600700
800900
1000
-40 -20 0 20 40
Temperature, F
Stre
ss, p
si
Control
SASOBIT
Estimated Thermal Stresses and Critical Cracking Temperatures
Comparison of Master Creep Compliance Curves
1.E-07
1.E-06
1.E-05
1.E-04
1.E+00 1.E+02 1.E+04 1.E+06 1.E+08 1.E+10
Loading Time, s
D(t)
, 1/p
si
Control
SASOBIT
19.0mm SMA
Sasobit: Mix temp 252ºF. Using tighter temp scale. Mat looks good.
Intelligent Compaction
• Improve Compaction Efficiency
• Improve Compaction Quality
• Real Time Information
• Identify Questionable Areas
• Improve Quality
ICC Draft Report
• Stiffness of Conventional Mix and Sasobit
were statistically the same with Sasobit
being placed 50°F cooler.
9.5mm with 35% RAP9.5mm with 35% RAP
350 F without Sasobit
SUMMARY• Reduce Mixing and Compaction
Temperature• Reduce Fumes• Reduce Fuel Costs• Improve Workability• Improve Density• Extend Paving Window• Improve Quality
With Sasobit you can:
