This document provides an overview of S.T.A.T.E. Testing's perspective on hot mix asphalt technologies from their base in Illinois. It discusses their team and experience working with various agencies. The bulk of the document outlines sustainable HMA technologies like warm mix asphalt, recycled asphalt pavement, ground tire rubber, and recycled asphalt shingles. It provides details on mix designs and performance testing of projects utilizing these technologies, including a Tollway WMA project, a CDOT low ESAL surface mix, a friction course, and the Michigan Avenue SMA project in Chicago.

1. Hey Buddy,
What’ll you have?

2. Jay Behnke, P.E.
President
S.T.A.T.E. Testing, LLC
Dundee and Chicago, IL
Behnke Materials Engineering
Beloit, WI
2
An HMA Perspective from the Land of
Gangsters and Cheese

3. 3
Our Sand Box

4. Pick a Good Team
4

5. Our Team:
5

6. Our Team:
The photogenic ones…
6

7. Agencies we work for:
7
1.Interest
2.Initiative
3.Courage
4.Available Projects
5.Short Decision Tree
6.Funding

8. Class Outline
 Mix Design Basics
 Sustainable Technologies
 Performance Testing
 Project Examples
8

9. 9
Gyratory Compactor
6 in.

10. 10
% Density
Gyrations90
NDESIGN
96%
(4% voids)
Gyratory Compaction

11. 11
How to Change NDESIGN
1. Aggregate Structure
• More Coarse Aggregate
• More Manufactured Sand
• Less Natural Sand
• Less dust
2. Asphalt Binder Content.

12. 12
VMA – Voids in Mineral
Aggregate
“Space between the Rocks filled
with Asphalt Binder and Air
Voids”
 Excludes Binder Absorbed into
the Aggregate
 Sets Minimum Binder Content for
Durability
 Varies with Aggregate Size.

13. 13
VMA
Voids in Mineral Aggregate
11%
4%
15% VMA

14. 14
Aggregate Surface Area
 One inch dia. rock makes 64 - ¼ in.
rocks
 Sum of the ¼ in. rocks have 4X
surface area.

15. 15
VMA Spec by Aggregate Size
Nom. Max.
Agg. Size
Minimum
VMA
Air
Voids
Effective
Binder
9.5 mm 15 % - 4% = 11%
12.5 mm 14 % - 4% = 10%
19.0 mm 13 % - 4% = 9%
25.0 mm 12 % - 4% = 8%

16. Field VMA
 Gmb
 Dust to AC ratio
 Contractor is
allowed to
remove dust
during production
16

17. 17
Field VMA: (f) % AC and Voids
Just a calculation – Uses existing
values
= 100 – (GMB * PS / GSB)
GMB: “d” from plant test
PS: % Stone = 100- %AC
GSB: Stone Specific Gravity from Design
e.g. = 100 – (2.415 * 0.94 / 2.687) = 15.5
Watch: If AC & Voids drop below mix
design values.

18. 18
Dust Silos
IDOT requires
“Positive Dust
Control”

19. 19
Mel Pod – Positive Dust COntrol
Weighs Dust
In and Out

20. Start-ups Illustrated
Test strip
required for
all new
mixes.
20

21. 21
Performance Graded Binder
“PG Binder”
(Asphalt Cement)
NOT “Polymer
Graded”

22. 22
PG Binder Nomenclature
PG64-22
Performance
Grade
Average 7-day
max pavement
design temp C
Min pavement
design temp C

23. ….without binder grade jumping.
23
2010
2012

24. 24
When to Modify?
 Extreme Temperatures
•Hot or Cold
 Heavy Traffic
•Especially Slow or Stopped
 Rutting or Shoving Problem Areas
 Concern re: Reflective Cracking
 Improve Film Thickness.

25. 25
Permeability Factors
 Increased Density  Lower
Permeability
 Smaller NMAS aggregate  Lower
Permeability (fewer interconnected
voids)

26. 26
Permeability can be measured

27. 27
Permeability vs.
Density and Nom. Max. Agg. Size
(NCAT)



28. Sustainable Options for HMA
28
RAP FRAP GTR WMA RAS

29. 29
Recycled Asphalt Pavement
(RAP)

30. 30
RAP Can Be Our Friend
 Quality
 Green
 Economical.

31. 31
RAP Works
 Processed
 Reasonable
Proportions
 Designed into
the mix
 < 20% - Acts as
“Black Rock.”
- Superpave Research

32. 32
Binder Grade for RAP Mixes
RAP% Binder Grade
≤ 20% Use Same PG Grade
> 20% Use Softer Grade
e.g. PG 58-28 for PG 64-22.

33. FRAP - Fractionated RAP
 Old – RAP was bad
 Then – RAP is OK
 Now – FRAP is great
33

34. IL FRAP Sizes (typical)
34
< #4 (0.2 in.)
#4 to 1/2 in.
> 1/2 in.

35. Observations - FRAP
 High Quality Grindings
 Higher RAP % does not affect production
 P#4 Material useful in SMA
• Angular
• Higher AC Content
 Bids reflect overall savings
 Less segregation
35

36. Fractionating FRAP Plant
36

37. GTR - Ground Tire Rubber Modified
Asphalt
37

38. GTR-Modified Asphalt
 AC modified with
recycled Ground Tire
Rubber (12-15%)
 Substitute for
polymer-modified AC
38
Vestenamer Stabilizer

39. Why GTR?
 Improved performance
• Rutting
• Resistance to oxidation
 Green - 2,000 tires per lane mile (2 in.)
 $$ ≈ Polymer-modified AC
 Replaces anti-draindown fibers
39

40. No Draindown
Replacement for Fibers.
 Open Graded
 Pervious
 SMA
40

41. GTR is Versatile
Since 2006:
 Green Alleys
 City Streets (low
ESAL)
 County Roads
(medium ESAL)
 Tollway mainline
(high ESAL)
 Bridge Decks
 Michigan Avenue
41

42. WMA - Warm Mix Asphalt
 Lowered emissions
 Less fuel consumption
 Worker health benefits
 Lower temps = Reduced
oxidation
 Extended paving season
• Haul time
• Compaction time
42

43. Warm Mix Technologies
 Chemical additives, e.g.
Evotherm
 Organic additives “wax”,
e.g. Sasobit
 Foaming –Astec Double
Barrel® Green
43

44. CDOT Warm Mix Asphalt
 6000+/- tons
 Produced @ 230˚ F
 Placed down to 180˚ F
 Same rolling pattern
 No difference in
workability
 Reduced odor, fumes

45. WMA Warm Mix Asphalt + RAS
on the Interstate
45

46. RAS
Recycled Asphalt Shingles
46

47. 2012 - RAS is the Law in Illinois
47

48. RAS = Quality HMA Ingredient
 Consistent gradation:
• 100% < 3/8 in.
• 93% < #4
 30+% High Quality Fine Aggregate
 26.4% High Quality AC
 27.8% Mineral Filler
• Shoot for 1:1 ratio (dust to AC)
 Mineral/Organic Fibers
48

49. High ESAL RAS
49

50. Field Performance
No time for TRB
 WMA
 GTR
 High ABR
 FRAP
 RAS
50

51. Illinois’ Performance Test
Hamburg Wheel
Torture Test for
 Stability
 Moisture
Resistance
51

52. Chicagoland Hamburg Criteria
 All WMA, RAS, & High-ABR mixes
52
Binder
# Repetitions
(Chicago)
Max. Rut
Depth
PG76-XX, PG70-XX 20,000
0.5 in.
PG64-XX, PG58-XX,
PG52-XX, PG46-XX
10,000
SMA 20,000 0.25 in

53. Passing the Hamburg Test
 GTR
 RAS
 Manufactured Sand
 Harder Rock (not
Limestone)
 Anti-strip additive
53

54. Direct Compact Tester
54

55. Performance Testing
Field Demonstration
Projects
Research Lab
Verification
55

56. 56
PROJECT EXAMPLES
 Tollway - Warm Mix
 CDOT – N30 LC
 IL 4.75 – Friction
Course
 Michigan Ave

57. Jane Addams Tollway
WMA, HMA, FRAP, RAS
57

58. Tollway Warm Mix Asphalt
 In 2012 the
Tollway was the
first agency in
the country to
mandate Warm
Mix Asphalt!!!
58

59. Tollway WMA - 2012
 762,000+ total tons (Magnificent Green 56
Miles)
 SMA mainline
• 304,000 tons
 N50 Shoulder Binder
• 204,000 tons
 N70 Shoulder Surface
• 210,000 tons
 Stabilized Subbase
• 8,400 tons
59

60.  Akzo Nobel
• “REDISET LQ”
 MeadWestVaco
• “EVOTHERM M1”
 Astec, Inc.
• “ASTEC WARM MIX
SYSTEMS”
 AQUABlack Solutions
• “MAXAM
AQUABLACK”
 Stansteel Asphalt
Plant Products
• “STANSTEEL ACCU-
SHEAR”
60

61. CDOT manages a lot of Asphalt
Paving…in a variety of locations
61

62. CDOT by the Numbers
$600-800 Million Annual Budget
(More than half from state or federal grants)
262 bridges and viaducts
4,091 miles of streets (excluding Expressways)
26,658 intersections (2,935 signalized)
10,646,110 feet of lane striping
12,145 bike racks
10,997 trees planted/year
59 stations and 50 miles of track owned by CDOT but
operated by CTA

63. CDOT Typical In-House Program
 2 Block increments
 4 Paving crews
• 2 street / 2 alley
 +/- 150,000 tons / year
placed
 Innovative mixture(s)
 Purchased from local
plants
 Rented equipment
63

64. 9.5mm N30 LC
Surface Mix
(Low ESAL)
Evolving over the years
 Increased % FRAP
 Added recycled PCC
 Added GTR
 Lowered PG grades
 Added WMA technology
 Added RAS
 % ABR
 Hamburg Tested
64

65. 9.5mm N30 LC Surface Mix
(Low ESAL)
65
ABR PG Binder
0-22% PG 64-22
23-45% PG 58-28
46-67% PG 46-34
Recycled Material Max%
Crushed PCC &/or
Coarse Aggregate
50% Total
Aggregate
Fractionated RAP 40%
RAS 7.5%

66. 4.75mm Friction Surface
 Not a “sand mix”
 Historically a
polymer-modified
mix
 RAS used as
modifier.
 Can be laid ¾”
thick!!
66
 HMA version of Micro Surfacing

67. Recycled Friction Aggregate
Chicago Expressways: Most
surfaced with slag friction
mixes and high quality AC
binder.
67

68. 4.75mm Friction Surface
New Specification
68
AGGREGATES PERCENTAGE
Natural Sand 40% Maximum
Manufactured Sand
15% Minimum
combinedManufactured Sand from Gravel;
or Steel Slag
Passing #4 portion of FRAP from
Steel Slag RAP; or Steel Slag 35% Minimum
combinedFine Aggregate from Steel Slag
RAP; or Steel Slag
RAS 7.5% Maximum

69. 4.75mm Friction Surface
New Specification
VOLUMETRICS
 NDES = 50
 Voids = 3.5%
 VMA = 18.5%
69
ABR PG Binder Max. RAS
0-22% PG 64-22 2.5%
23-45% PG 58-28 5.0%
46-67% PG 46-34 7.5%
High ABR

70. 4.75mm High ABR Surface
2011 Demonstration
%
MIX
AC
Content ABR
FRAP (1) 8% 4.8% 0.4%
FRAP (2) 30% 5.8% 1.7%
RAS 7.0% 26% 1.8%
3.9%
Design AC 8.0%
New AC 4.1%
AC Savings $28 / Ton
70

71. Pulling it Together
Michigan Avenue SMA
71

72. Environmental Leadership Award
2012 NAPA
72

73. Examination
Given:
 Location
 Variable
Base/Subbase
 300 Structures to
work around
 Time Constraints
 Green Objectives
Solve for:
1. Milling Thickness
2. Lift Thickness
3. Binder Mix
4. Surface Mix
5. Tack Coat
6. Paving Width
7. Maximum ABR
73

74. Factors favoring Single SMA Lift
 Uncertainty of Base
 Time
 Cost
 SMA Characteristics
74

75. Michigan Ave SMA
Mix Design
MIXTURE OIL
Quartzite 12.5mm 50%
Quartzite 9.5mm 24%
FA & Mineral Filler 3.5%
RAP < 3/8 in. 15% 0.8%
RAS 7.5% 2.0%
PG 58-28 GTR+12 6.1% 3.3%
6.1%
VOLUMETRICS
 NDES = 80
 Voids = 3.5%
 VMA = 16.3%
 VFA = 78.5%
75

76. Torture Tested (cores)
76
< 4mm rut

77. Test Strip at Plant
77

78. Paving
78

79. Logistics & Traffic Control
79

80. Sweeping for Prime was an Art
in Itself
80

81. + Trackless Tack/Prime Coat
81

82. Completed in 6 consecutive
nights of Paving
82

83. Daily Temperatures
Oct-2011
16 17 18 19 20 21 22
High 52°
Low 27°
53°
27°
57°
30°
61°
27°
62°
40°
54°
31°
60°
36°
Historic Averages
54°/30° 53°/29° 52°/29° 52°/28° 51°/28° 50°/27° 50°/27°
83

84. Compaction – 3 static 3-wheeled;
Large Tandem Finish
84

85. Street Returns
85

86. Hand Workable
86

87. Quality Control
Std.
Dev.
Tolerance
GMM 0.003 +/-.030
GMB 0.006 +/- .026
Voids 0.25 +/- 1.00
VMA 0.150 +/- 0.70
AC 0.16 +/- 0.03
Dust:AC 0.07 +/-1.20
 4 Samples
 1 set per night
 > 700 Tons per
night
87

88. Finished Product
88

89. Details
89

90. The End – Thank You
90