Transcript Pavement Preservation in South Carolina

Pavement Preservation
in South Carolina
J. C. “Clem” Watson, P.E.
Chief Engineer for Operations
South Carolina Department of
Transportation
Why is pavement preservation
important to SCDOT?
Money and Miles
Miles
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SCDOT maintains the 5th largest road
system in the nation.
Approximately 41,500 centerline miles
Over 90,000 lane miles
Money
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Lowest receipts per mile in the nation
SCDOT receives $31,685 per mile
National average is $128,538
What does this have to do
with preservation?
 Economics
– preservation is
cheaper to perform with more
bang for your buck
Treatment Comparison
Reconstruction
20
$200,000
Cost per
Lane Mile
Year of
Service Life
Added
$10,000
Rehabilitation
15
$130,000
$8,666
Preservation
5
$20,000
$4,000
Treatment
Type
Design Cost per
Life
Lane
Mile
Keys to Success
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Roads have to be in good condition
Use the right treatment on the right road
at the right time
Must have a well-qualified contractor
Should have dedicated funding
Challenges
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Getting away from worst first
Educating the public
Industry resistance
Optimize Treatment Selection
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Find the optimal combination of
Reconstruction, Rehabilitation, and
Preservation Treatments
Goal is to increase the Remaining Service
Life (RSL) of the system while addressing
some of the really bad roads and
minimizing the amount becoming really
bad
Bucky the Beaver
SCDOT’s Strategy
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Use Pavement Management data to
categorize road candidates
Distribute the maintenance funding to
each category based on the estimated
cost of need for that category
Example of SCDOT’s
Federal Aid System
Project
Category
Miles
of
Need
Cost of
Need
Percent
by Cost
Preservation
7,109
$408 M
9%
Rehabilitation
7,674
$2,771 M
59%
Reconstruction
3,315
$1,487 M
32%
Types of Preservation Surface
Treatments used by SCDOT
1.
2.
3.
4.
Crack Seal
Chip Seal
Microsurfacing
Ultra-Thin Asphalt Overlays
Which treatment?
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Pavement condition
Traffic volumes
The location of the road (rural or urban)
The availability of materials and approved
contractors
The cost effectiveness of the treatment
Volume of work
Table 7: Treatment Selection Matrix
Crack/Joint Seal
Emulsion
Modified Rubber
Chip Seal
PME - Lightweight Agg.
PME - Crushed Granite
Microsurfacing
Ultra Thin Lift Asphalt Overlay
Full Depth Patch
Good Performance
Fair Performance
Poor Performance
Not Recommended
Not Used
The quantity and/or severity that are listed for each distress indicate the
degree that is considered significant. See Appendix A for a description of
these distresses and severity levels.
*Does not include isolated areas that can be repaired with a full depth patch.
Rural
Urban
High
Medium
Low
IRI > 170
IRI < 170
> 4% Low
> 2% Medium
0 to 2% High
4 to 25% Low
2 to 10% Medium
> 1/2"
< 1/2"
Bleeding
Oxidation
Raveling
Treatment
0 to 2% High
Distresses
Parameters
Rutting
Cracking
Roughness Traffic Vol.
Fatigue* Long./Trans.
Life Cycle Cost
Treatment
Cost/LM
Life
Expectancy
(Yrs)
Crack Sealing
$2,395
2–3
$958
Chip Seal
$12,354
5–7
$2,059
Microsurfacing
$25,588
5–7
$4,265
Ultra-Thin
Asphalt Overlay*
$30,628
6–8
$4,375
*If milling of the pavement is required these costs will increase
Life Cycle
Cost ($/Yr)
Summary
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SCDOT could not adequately maintain our
large system with the limited resources
available without a pavement preservation
program
Without preservation, it’s easy to see how
quickly our system would deteriorate
Treatment selection critical for success
Questions?