warm mix asphalt - apwa · evotherm 1 warm mix asphalt can your community benefit from this green...

EVOTHERM

1

Warm Mix AsphaltCan Your Community Benefit from this

Green Technology?Green Technology?

John I. Duval, P.E., LEED APTechnical Marketing Manager, Evotherm

APWA International Public Works CongressSeptember 14 2009September 14, 2009

Columbus, Ohio

Outline

• What is Warm Mix Asphalt?• Why Warm Mix Asphalt?

– Pavement Performance– Environmental Benefits

• Case Study

EVOTHERM

2

What is Warm Mix

• Reduce production temperatures 30°-100°F

• Many additives & processes• First developed in EU in mid-90’s• NAPA WMA EU Scan Tour 2002• First US sections paved in 2004

What is Warm Mix

• First US Evotherm projects paved in 2005

• NCAT lab/track studies in 2005• First DOT sponsored test sections in

2006• Projects in 40+ states by 2009

EVOTHERM

3

States that have placed WMA

What is Warm Mix?

2005: There were three WMA technologies:Aspha-min – foam zeoliteSasobit – waxEvotherm – surfactant

2009: > 10 Warm mix technologiesWith many differences including

» WMA mechanism» Effective temperature range» Track record of performance

EVOTHERM

4

WMA Additives / Foam Systems

• Advera • Astec Double B l G• Aspha-Min

• Evotherm• LEA-CO• Low Emission

Asphalti

Barrel Green• Gencor Green

Machine• Maxam

Aquablack• Stansteel Accu-• Rediset WMX

• Sasobit• WAM Foam

• Stansteel Accu-Shear Dual WMA

• Terex WMA System

What is Warm Mix?350ºF

Conventional Hot Mix º

250ºF

200ºF

Hot Mix 300ºF

Warm MixAsphalt

FoamedAsphalt

Cold MixAmbient

EVOTHERM

5

Why Warm Mix?

• Lowest Temperatures– 70 - 100°F cooler than HMA– Large compaction window– Reduced thermal segregation – Extended hauls & paving season– Longer service lifeg– Major reductions in fuel & emissions– Increased usage of RAP

Why Warm Mix?

• Larger compaction window

EVOTHERM

6

Texas DOT - San Antonio

LimestonePG76-223000 T 3000 Tons, T mix: 240°FΔT: 95°F

TxDOT DensitiesRoadway & Lab Densities @ 4.6% PG76-22

98.0 98.0

94.0

92 593.1

97.297.0

96.3

92 0

93.0

94.0

95.0

96.0

97.0

Rdw

y D

ensi

ties

96.0

96.5

97.0

97.5

ab M

olde

d D

ensi

ties

Rdwy Density

Lab Density

92.5

90.0

91.0

92.0

WMA HMA Control HMA Project95.0

95.5

La

EVOTHERM

7

TxDOT Specification Bonus

Roadway Densities TxDOT Specification % Bonus

94 5

WM

A

ontr

ol

ect92.5

93.0

93.5

94.0

94.5

2.0% Bonus

3.2% Bonus

5% Bonus

Evot

herm

HM

A C

o

HM

A P

roje

91.5

92.0

Averages

E

Advantages of Warm Mix

• Larger compaction window• Reduced thermal segregation

EVOTHERM

8

62 Deg Difference

24 Deg Difference

EVOTHERM

9

Advantages of Warm Mix

• Larger compaction window• Reduced thermal segregation• Extended hauls & paving season

Extended HaulsDoubling Market Reach

70 miles

50 miles

EVOTHERM

10

Double Haul Distance50 vs. 100 mi

4X4X

HMA at 50ºF

EVOTHERM

11

Evotherm at 50ºF

Extended Season Paving

New York City, 8 Dec. 08, 40% RAP PG 64-22

Evotherm mix temperature behind the screed

Ground temperatureat 7 a.m. was < 15ºF

EVOTHERM

12

Extended Season Paving

New York City, 8 Dec. 08,

40% RAP PG 64 2240% RAP PG 64-22

Paving

Compaction

Extended Season Paving

New York City, 8 Dec. 08,

40% RAP PG 64 22

Excellent joint compaction

40% RAP PG 64-22

Air voids of coresall > 92% of Gmm

EVOTHERM

13

Cold Weather Paving

280 mile, 8 hour haul

10°F air temperat re10°F air temperature

Bridge resurfacing

350°F production

240°F delivery

Advantages of Warm Mix

• Larger compaction window• Reduced thermal segregation• Extended hauls & paving season• Longer service life

EVOTHERM

14

Reduced Binder Aging

120

140Hot Mix

40

60

80

100

120Pe

nEvotherm

0

20

Virgin AC RecoveredAC

2 years

TxDOT Cores After 1 Year

Hot Mix Control

EVOTHERM

15

TxDOT Overlay Tester

StressStress Crack

TTI Overlay Tester Results

841*

800

900 HMA GRANITEEVOTHERM GRANITE

108

593

321

597.3634**

200

300

400

500

600

700

CY

CL

ES

TO

FA

ILU

RE

2954

08

41 58.0

0

100

1 2 3 4 MEAN

SAMPLE * Test stopped at 841 cycles without failure** Test stopped at 634 cycles without failure

EVOTHERM

16

TTI Overlay Tester Results

490500

600 HMA LIMESTONEEVOTHERM LIMESTONE

419

490

345 334

397.0

200

300

400

500C

YC

LE

S T

O F

AIL

UR

E

31 21 20 30 25.5

0

100

1 2 3 4 MEAN

SAMPLE

Advantages of Warm Mix

• Larger compaction window• Reduced thermal segregation• Extended hauls & paving season• Longer service life• Major reductions in fuel j

consumption and emissions

EVOTHERM

17

Mayors Climate Protection Agreement

971 cities as of 9/14/09

www.usmayors.org

Stack Emissions

100%

120%HMA emission normalized to 100%

0%

20%

40%

60%

80%

100%

Fuel CO2 CO SO2 NOx TPM

Hot Mix

Evotherm↓46%

↓63%

↓34%

↓58%

↓81%

↓55%

200 °F Evotherm, 310°F HMA control

EVOTHERM

18

Reduced Emissions

Hot Mix

Reduced Emissions

Hot Mix

EVOTHERM

19

Evotherm

Jobsite Emissions vs. HMA

0 4

0.8

1.2

1.6

2Evotherm

HMA

↓41%Below

DetectableLimits↓

0

0.4

Total Organics Benzene Solubles

Jobsite Emissions

HMA Control Lower ProductionTemperatures MeanSi ifi tl LSignificantly Lower

Fumes & Odors

Evotherm

EVOTHERM

20

Mexico City – EcoPaving45% reduction in fuel consumption & CO2 emissions

City owned & City owned & operated mix plants

100% of HMA production converted to Evotherm

Advantages of Warm Mix

• Larger compaction window• Reduced thermal segregation• Extended hauls & paving season• Longer service life• Major reductions in fuel j

consumption and emissions• Increased usage of RAP

EVOTHERM

21

Increased RAP

Source: D. Williams - MoDOT

High RAP Binder PropertiesProperty 40% RAP

HMAControl

40% RAPEvotherm

WMA

SuperpaveSpecification

Mix Production Temperature, °F 330 248 not applicable

Viscosity (Pa-s) 1.357 1.017 3 Pa-s max.G*/sinδ at 64°C, kPa 9.60 5.31 not applicable

to fieldbinder

samples

G*/sinδ at 70°C, kPa 4.54 2.59G*/sinδ at 76°C, kPa 2.18 1.27G*/sinδ at 82°C, kPa 1.08 0.642G*/sinδ at 88°C, kPa 0.56 -Penetration (dmm) 15 23 not applicablePenetration (dmm) 15 23 not applicable

BBR Stiffness (MPa) 222 158 300 MPa max

m-value 0.296 0.328 0.300 minPressure Aging Vessel G* x sinδ, kPa 5663 3218 5000 kPa max

EVOTHERM

22

Case Study

• City of Portland, Oregon

• WMA Demonstration Project

Evotherm—What is it?

• Comprehensive additive packagep p g• Optimized to deliver

– Mixing– Coating– Workability– Compaction– Adhesion

EVOTHERM

23

Evotherm—How does it work?

• Introduced into asphalt binder at terminal--0.3-0.7% by asphalt weight

• Effective temperature range– Mix temperature 250-170°F– Compaction temperature 235-150°F

Advantages of Evotherm

• Easy to use– Can be produced in any mix plant– Same production & lay down

equipment as conventional mix– Easy mix design evaluations

No plant modifications– No plant modifications– Zero capital investment – lab or plant

EVOTHERM

24

Evotherm 3G

Advantages of Evotherm

• Proven track record of performance– Hundreds of projects– 9 independent studies– 15+ DOT Evaluations– 10+ million ESAL on NCAT Test Track

• < 2 mm of rutting• < 2 mm of rutting

EVOTHERM

25

City of Portland WMA Demo

City of Portland WMA Demo

PG64-22, 30% RAP

Mix Temp 250F

ΔT ~ 85°F

EVOTHERM

26

City of Portland WMA Demo

PG64-22, 30% RAP

Placement Temp p225F

City of Portland WMA Demo

Mat Densities

93-95% of TMD

EVOTHERM

27

City of Portland WMA Demo

City of Portland WMA Demo

HMA Evotherm WMAAsphalt PG 70-22 PG 70-22Mix ½ NMAS ½ NMASMix Temp 335F 250FBreakdown 300F 215FFinish 180F 160FFinish 180F 160FDensity 92-93% TMD 93-95% TMDRAP 30% 30%

EVOTHERM

28

Thank you!y