PAVEMENT MAINTENANCE 1
Part 3: Potholes and Cracks
Idaho
Roads Scholar
Program
Objectives
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Explore alternatives for repairing
potholes,
Review options for extensive
patching,
Investigate methods and materials
for treating pavement cracking.
HOW A POTHOLE DEVELOPS
HOW A
POTHOLE
DEVELOPS
Elements of Successful
Pothole Patching

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Use high-quality patching
materials, which are costeffective compared to less
expensive products.
Place--do not throw-material in the patch area.
Compact every patch.
High Quality Cold Mixes Include:

Carefully selected aggregate types
and gradations
 Very
clean, durable aggregates
 Very little sand-mixtures are
porous


Polymer modified binder
Additives that promote adhesion in
wet conditions
Asphalt Cold Patch Materials


Standard Spec 00745.00 Asphalt Cold
Patch-High Performance
Qualified Products List available describing
suitable materials
“There’s a gentleman here to see you about potholes.”
Permanent Repairs
Dig Out and Repair
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Identify area affected
Remove to sound material
Clean, tack edges
Place patching mixture
Compact
Check level
Mark Area to be Patched
Mark patch area, extending at least 1 foot outside of
distressed area.
Remove Failed
Materials
Place Patching Mixture
Spread Mixture Carefully
Compact Each Lift
Thoroughly
Straight-edge the Patch
Blown-in Pothole Filler
Blown-In Filler
The hole is
cleaned with a
high volume
blower.
A tack coat
of asphalt is
applied to
the area.
A mixture of
aggregate and
hot asphalt fills
the hole.
SPRAY INJECTION
A finish coat
of aggregate,
and traffic
flows.
Patching Rules of Thumb

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Dig out 1 foot beyond the visible
cracking
Don’t rock the jackhammer
Dig out at least 1 1/2 times the
thickness of the failed AC
Compaction, compaction,
compaction.
Questions?
Crack Treatments
Purpose


Used to prevent water
and debris from
entering individual
cracks in the asphalt
pavement surface
Crack treatments are
both a corrective and
preventative
maintenance
treatment.
Crack Sealing
Feasibility
Extent of Problem
Distress Type Minor
Fatigue Cracking
Linear & Block Cracking
“Stable” Rutting
Raveling
Flushing/Bleeding
Roughness
Friction Loss
Moisture Damage
Shoving
Major
Feasible
Not Appropriate
Crack Sealing
Effectiveness
Extent of Problem
Distress Type Minor
Fatigue Cracking
Linear & Block Crack
“Stable” Rutting
Raveling
Flushing/Bleeding
Roughness
Friction Loss
Moisture Damage
Shoving
Major
Effective
Marginal
No Impact
Crack Repair Guidelines
Crack Width
Treatment Options
< 1/8 inch (3 mm), nonworking
Do nothing
 Fog seal
 Surface treatment (chip seal,
slurry, etc.)
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
1/8 – 3/4 inch
(3 – 19 mm)
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> 3 /4 inch (19 mm)
Crack Fill (short life, prep for
resurfacing)
 Crack Seal (> 5 yr life)
Filling (sand or sand-emulsion
slurry)
 Patching (cut and replace
material)
Don’t do this!
Or this!
Proper Crack Sealing Technique
For Effective Crack Sealing:
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Perform sealing during late fall/early spring
when cracks are open.
Sealing does not proceed if rain is imminent.
Ambient or surface temperature should meet
manufacturer’s requirements—usually 40F
and rising for routing and sealing.
Use appropriate materials.
Preparation is Key!
 Spray
the weeds in advance
 Clean the pavement surface.
 Provide for traffic control.
 Clean the crack, removing any
moss or grass out of crack.
 Dry the crack if necessary. (Hot air
lance)
 Fill it with crack seal material.
 Apply something to surface of seal
to minimize the tackiness.
Pavement Preparation

Cleaning and Drying
 Broom
 Compressed Air
 Sandblasting
 Hot Air
Blasting (Heat Lance)
Cracks Must Be Clean & Dry
Use Compressed Air
Note: Be Sure Compressor Is Equipped With A
Moisture Trap
...Or Clean with a Hot Air Lance

Up to 3000°F

> 2000 ft/sec blast velocity

Propane burner-no flame
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Conducted immediately ahead
of sealant installation (5 mins or
50 yards max)
Comments:

For wet conditions, lance can improve performance

Otherwise, compressed air may be more effective (Québec
study)
Rout and Seal
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Cut the pavement
to a prescribed
width and depth
Improves sealant
performance
 Better
adhesion
 Reduced tensile
stress on
material
Crafco, Inc
Crack Sealing
W
D
Typical Dimensions:
W = 0.5” to 0.75”
D = 0.5” to 0.75”
Traffic Control
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Detour traffic until seal cures
Cover sealant with sand for quick
opening
Begin filling at pavement centerline
Blotting Materials
Dry sand
Toilet paper (proven effective
in SHRP research!)
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Crack Seal Materials

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Standard Spec 00746.00 Poured Filler/ Hot
Poured
Qualified Products List available describing
suitable materials
Crack Seal
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The most common product used: D1190
Cost per pound: $0.26
Cost per linear foot to crack seal: $0.40
Should reseal after 5 years?
Crack Sealing
Crack Sealing Rules of Thumb
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For linear cracks only (not intended
form alligator cracking)
Clean cracks with forced air or
heat lance
Don’t over-fill crack with sealant;
avoid surface smears
Sweep up excess sanding
Review



Investigate methods and materials
for treating pavement cracking,
Explore alternatives for repairing
potholes,
Review options for extensive
patching.
Questions?
Small Group Activity



Identify the distress
Describe the cause
Outline the optimum
maintenance repair
10 Minutes
Photo No. 1:
Photo No. 2:
Photo No. 3:
Photo No. 4:
AI 38: Use for Group
Photo No. 5:
AI 30: Use for Group
Photo No. 6:
AI 47: Use for Group
Photo No. 7:
AI 47: Use for Group