Presentation by Brandon Milar, P.E., Technical Director, California Asphalt Pavement Association (CalAPA) to the Transportation Research Board 98th Annual Meeting, Jan. 13, 2019 in Washington, D.C. Event No. 1068. Presentation No. P19-21237. Topic title: Contractor Experience with Smoothness Specifications

1. The California Asphalt Pavement Association
TRB 98th Annual Meeting, January 13-17, 2019, Washington, D.C
Pavement Smoothness Specifications Lessons Learned
Event Number: 1068 Presentation Number: P19-21237

2. Promoting
Learning
Advocating
Networking
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3. Members of CalAPA
Don Matthews – Pavement Recycling Systems
Caltrans
Tom Pyle – Caltrans
Tim Greutert – Caltrans
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4. 4

5. Asphalt Concrete
Medium & Coarse Gradations
Binder: AR & PBA  PG
Method & Density
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2006 2010 2015
Hot Mix Asphalt (HMA)
3 Construction Processes
(Method, Standard & QC-QA)
Superpave
Gyratory & Hamburg

6.  Pre 2012:
 California Profilograph
 Straightedge
 2012 and beyond:
 Inertial Profiler
 Straightedge
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7. TheTravelling Public Gets It!!!!
 Provides a comfortable ride
 Lasts longer
 Stays smoother longer
 Is safer
 Saves money (pavement and vehicle repairs and fuel
economy)
 Is better for the environment

8. Best practices learned during the transition
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9.  Head of Material on Screed
 Paving Speed
 MixTemperature
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10.  Reference a portion of
pavement that is smooth
 Reference a smooth, cold
planed surface that was cut
with an averaging system
 Don NOT reference a cold
planed surface that
 Trust the Equipment
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11. 11

12.  Use a good control system (i.e.
an averaging system) on the
existing surface
 Following an existing rough
surface at constant depth will
transfer the roughness to the
bottom of cold planed surface.
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13. Proper maintenance of
mechanical systems
Proper maintenance and
replacement of cutting tools
and blocks
Smooth transitions in and out
of cuts
Clean the milled surface
Do NOT stop drum in the cut
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14. 14
Micro Milled Surface Standard Milled Surface
Micro Milling Drum
Standard Milling
Drum

15. OUTRUNNINGTHE PATTERN SPEED ANDTEXTURE
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16. 16

17.  The Preferred
ChoiceWhen
Required to Cut to
Specific Grades at
Specific Elevations
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18. 18
Uses GPS to Position Horizontally with Scanned Surface for Vertical Road Surface
Can use LiDAR

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20.  Initial Caltrans Smoothness
Requirement (Circa 2014)
 What about:
 Location?
 RoadType?
 Opportunities?
 Existing smoothness?
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21. 21

22. 22
0.20' Mill and Fill with SAMI
75 MRI
Existing Breakdown
> 85 66%
> 135 31%
> 165 14%
> 200 7%
> 331 0%
0.1' Mill and Fill
75 MRI
Existing Breakdown
> 85 17%
> 135 1%
>164 0%

23.  Specification applied a simplified requirement for ALL
pavement conditions.
 Pavement design may or may not address the existing
smoothness condition.
 Specification assumes that design is appropriate for existing
pavement smoothness
 Specification use and enforcement inconsistent from project
to project.
 The above leads to bidder confusion, disputes, and claims

24. Recent revisions tried to “bite off more than it can
chew.”
No data to support limits
Lack of incremental approach to improvement
Significant and unnecessary risk placed on the
contractor.

25. Many Claims and Disputes
Large Losses - Both Contractors and State

26.  Increase gas tax funding – DOUBLED!!!
 Requires performance criteria in 10 years
Includes Statewide Network SmoothnessTargets
 PMS triggers for roadway correction
Deformation
Cracking
SMOOTHNESS!!!
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27.  In a partnered/collaborative environment
 Development of new specifications should be “data-driven.”
 Specifications should be uniform and consistent in
application and acceptance.
 Specifications should be “street ready.”

28. Rehabilitation of Asphalt Concrete Pavements: Initial
Evaluation of the SPS-5 Experiment—Final Report
FHWA-RD-01-168
“The age of the overlay, condition of the pavement before
overlay placement, and surface preparation or milling depth
were factors found to be important relative to the IRI values.
The IRI values of the overlay were found to be lower for the
overlays placed over pavements in the fair category and
when the existing surface was milled before overlay.
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29. 12 projects
4 – 1 lift over CIR
5 – 1 lift Mill & Fill
3 – 1 thin lift
Multiple contractors
Multiple Districts
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30. 135 MRI
75 MRI
Initial MRI
FinalMRI
Single Opportunity – Lift of Asphalt

31.  Use an equation to relate paving expectation for a single lift opportunity
based on an existing pavement smoothness.
MRIt = 0.3 * MRI0+35
MRIt = 0.1 mile segment MRI target value
MRI0 = existing pavement MRI for the 0.1 mile segment
▪ For each opportunity, re-apply the equation for each opportunity (i.e. for 2 opportunities
MRIt=0.09*MRI0+45.5)

32. Example: Single lift overlay
Use the equation: MRIt = 0.30 x MRI0 + 35
MRI0 MRIt
135 75
165 85
210 98
250 110

33. Example: “Mill & Fill” with 2 lift overlay
Use the equation: MRIt = 0.09 x MRI0 + 45.5
MRI0 MRIt
135 58
165 60
210 64
250 68

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All 0.10 mile sections above 135 MRI Baseline – Target % Improvement
All 0.10 mile sections at or below 135 MRI Baseline – Target 75 MRI
Target MRI is 83.6 in/mi

35. 35

36. Pay AdjustmentTable
Total AsphaltThickness
(ft.)
Baseline 0.1-mi MRI
(in/mi)
HMA Final MRI (in/mi)
Adjustment Table
≥ 0.30
<165 Target 60
≥165 Percent Improvement
< 0.3
<135 Target 75
≥135 Percent Improvement
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Total AsphaltThickness = layer thickness that is
constructed in the segment (excluding OGFC)

37. 37
Target 60 Pay Adjustment
MRIseg
(in/mi)
Pay Adjustment
(per 0.1’ mile)
Corrective Actions
(MRI)
≤ 45.00 $900.00 None
45.01 – 55.00 + ((55.00 – MRIseg) x
$90.00)
None
55.01 – 65.00 Full Pay None
65.01 – 80.00 - ((MRIseg – 65.00) x
$190.00)
Optional
> 80.00 Not Applicable Mandatory

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Target 75 Pay Adjustment
MRIseg
(in/mi)
Pay Adjustment
(per 0.1’ mile)
Corrective Actions
(MRI)
≤ 60.00 $450.00 None
60.01 – 70.00 + ((70.00 – MRIseg) x
$45.00)
None
70.01 – 80.00 Full Pay None
80.01 – 90.00 - ((MRIseg – 80.00) x
$135.00)
Optional
> 90.00 Not Applicable Mandatory

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Percent Improvement Pay Adjustment
MRIseg
(in/mi)
Pay Adjustment (per 0.1’
mile)
≥ 0.25’
Pay Adjustment (per
0.1’ mile)
< 0.25’
Corrective
Actions (MRI)
PoT ≤ 75% $900.00 $450.00 None
75% < PoT < 90% $900.00 - ((PoT – 75.00) x
$60.00
$450.00 - (PoT-75.00)
x $30.00
None
90% < PoT < 110% Full Pay ($0.00) Full Pay ($0.00) None
110% < PoT < 125% -(PoT – 110.00) x ($190.00) -(PoT – 110.00) x
($135.00)
Optional
If MRISEG ≤ 90 in/mi
and PoT > 125%
-(PoT-110.00) x ($190.00) -(PoT-110.00) x
($135.00)
Optional
If MRISEG > 90 in/mi
and PoT > 125%
Not Applicable Not Applicable Mandatory

40. 40
40
60
80
100
120
140
90 110 130 150 170 190 210 230 250
MRI-Acceptance
MRI - Initial
MRITarget and Ranges - 1 Opportunity
MRIt-25 MRIt-10 MRIt MRIt+10 MRIt+25
Full Pay
Incentive
Mandatory Correction
Dis-Incentive

41. 0.20' Mill and Fill with SAMI
75 MRI
Existing Breakdown
> 85 66% Table 75
> 135 31% % improvement
> 165 14% % Improvement
> 200 7% % Improvement
> 331 0%
0.1' Mill and Fill
75 MRI
Existing Breakdown
> 85 17% Table 75
> 135 1% % Improvement
>164 0%
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42.  Pilot Projects in 2019
Train designers on process to evaluate projects for smoothness
and incorporate corrections
Train DOT REs on specification administration
Train contractors on specification requirements and construction
BMPs.
Collect field data and refine equation and specification
requirements.
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43. 43

44. Brandon Milar, P.E.
Director ofTechnical Services
California Asphalt Pavement Association (CalAPA)
916-791-5044
bmilar@calapa.net
www.calapa.net
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