TOWN OF NEW CASTLE
DEPARTMENT OF
PUBLIC WORKS
POTHOLES & OTHER FORMS OF
PAVEMENT DISTRESS
March 24, 2015
PAVEMENT DISTRESS
• Four Major Categories
– Disintegration (potholes, etc.)
– Cracking
– Surface Deformation
– Surface Defects (bleeding, etc.)
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DISINTEGRATION
• Potholes
– Disintegration is the
progressive breaking up of
pavement.
– Caused by moisture
infiltration and usually
alligator cracking.
– Can be repaired with
patching, depending on
severity.
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CRACKING
• Fatigue Cracking
– aka Alligator Cracking
– Caused by traffic loading
and base and drainage
conditions.
– Can be repaired by patch
or area repair.
• Traverse & Longitudinal
Cracking
– Caused by thermal issues.
– Can be repaired by sealing,
patching or area repair.
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SURFACE DEFORMATION
• Depressions
aka Bird Baths
– Caused by localized
consolidation or movement
of supporting layers
beneath surface.
– Can be repaired with
patching.
• Swells
– Caused by localized
upheaval movement in
pavement due to swelling
due to frost.
– May require reconstruction.
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POTHOLE CAUSES
• Potholes are generally
caused by moisture,
freeze-thaw action,
material fatigue, traffic,
poor underlying
support, or some
combination of these
factors.
• Pavement chunks are
dislodged, resulting in a
pothole
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POTHOLE REPAIR OPERATIONS
Pothole repair operations can usually be
divided into two distinct periods:
• Winter repairs
• Spring repairs
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Winter Repair Operations
• Temperatures are low
• Base material is frozen
• Additional moisture and freeze-thaw
cycles are expected
• Any repairs are very temporary
• Repairs may be “cold patch”
• Placement of “loose millings”
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Spring Repair Operations
• Base material is wet and soft
• Few additional freeze-thaw cycles are expected
• Repairs are “semi-permanent” provided that the
ground and air temperatures are above freezing
• Ideally, air temperatures should be above 45 F
• We use “hot box” to reheat re-usable mix
• If plants are open, we use fresh asphalt
• Potholes must be dry
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“HOT BOX”
Used to Place Heated Asphalt Mix Into Potholes
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POTHOLE REPAIR TECHNIQUES
1.
2.
3.
4.
5.
Remove loose debris
from pothole
Dry out the pothole by
forced air and/or heat
Coat inside of hole with
“tack coat”
Place hot mix asphalt
into hole
Use vibratory compactor
to “pack in place”
Picture of a Pothole
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POTHOLE REPAIRS
STEP 1 – Remove loose debris
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POTHOLE REPAIRS
STEP 2 – Dry out the pothole
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POTHOLE REPAIRS
STEP 3 – Coat inside with “tack coat”
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POTHOLE REPAIRS
STEP 4 – Place hot mix asphalt
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POTHOLE REPAIRS
STEP 5 – Compact asphalt into hole
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GENERAL REPAIR TECHNIQUES
• Patching
– Patching is done year-round and can be very
economical. Patching will do the following:
• Fill potholes
• Repair of:
– Ruts
– Slippage
– Pavement defects
– Does not address base defects.
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GENERAL REPAIR TECHNIQUES CONT’D
• Area Repairs
– Unlike patching, area repairs involve a more
extensive repair.
– Area repairs involve a cut out and
replacement of a bad section of road.
– Relatively expensive, however it does
address base problems and is not wasteful.
– Best alternative to small areas of distress.
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GENERAL REPAIR TECHNIQUES CONT’D
• Reclamation
– Improves base.
– Grading is done to re-establish the “crown.”
– Various binder compounds may be used in the
recycled base.
– When completed properly, it provides an almost new
road.
– Technique was first done in Westchester, in New
Castle, 29 years ago.
– Very cost-effective.
– Will continue to be used in New Castle as needed.
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ROAD MAINTENANCE
•
Four different categories:
– Demand
• Technique to correct hazard or service request.
• Spring pothole repairs is command demand maintenance.
– Routine
• Routine basis for operational reasons.
• Examples: Mowing grass, cutting shoulders, and road stripping.
– Preventative
• DRAINAGE IMPROVEMENTS ! ! !
• Prevention of significant deterioration, extension of pavement life.
• Planned surface treatments.
– Corrective
• Repair pavement failures after they have occurred.
• Generally costs more than preventative or routine maintenance.
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ANY QUESTIONS ?
• Please contact DPW at 238-3968
• Please post messages regarding potholes
at: [email protected]
Presentation prepared by Golden and Moerschell, with photography by Carey
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