Longitudinal cracks, 1/4" to 1/2" some spaced less than 10'
First sign of block cracking
Slight to moderate flushing or polishing
Occasional patching in good condition
Shows signs of aging
Structural condition is sound
Life can be extended with a seal coat
PASER Scale
Rating: 5 - Fair
Moderate to severe raveling
Longitudinal and transverse cracks open 1/2"
Shows signs of slight raveling in secondary cracks
Longitudinal cracks near pavement edge
Block cracking over 50% of the surface
Extensive to severe flushing or polishing
Some patching or edge wedging in good condition
Surface is aging
Structure is still sound
Can be repaired with seal coat or thin non-structural overlay (<2")
PASER Scale
Rating: 4 - Fair
Severe surface raveling
Multiple longitudinal and transverse cracking with slight raveling
Longitudinal cracking in wheel path
Block cracking over 50%
Patching in fair condition
Slight rutting or distortions 1/2"
Significant aging and first signs of need for strengthening
Would benefit from structural overlay (2" or more)
PASER Scale
Rating: 3 - Poor
Closely spaced longitudinal and transverse cracks showing raveling and crack erosion
Severe block cracking
Some alligator cracking (<25% of surface)
Patches in fair to poor condition
Moderate rutting or distortion (1-2" deep)
Occasional potholes
Needs patching and repair prior to major overlay
PASER Scale
Map of Oakwoods Subdivision
The evaluation of the subdivision streets included ratings of 10, 6, 5, 4, and 3.
The majority of the streets fall within the middle to lower end of the scale.
Terminology
Raveling
Raveling is progressive loss of pavement
material from the surface downward,
caused by:
stripping of the bituminous film from the aggregate
asphalt hardening due to aging
poor compaction (especially in cold weather construction)
or insufficient asphalt content
Slight to moderate raveling has loss of fines.
Severe raveling has loss of coarse aggregate.
Raveling in the wheel paths can be accelerated by traffic.
Protect pavement surfaces from the environment
with a sealcoat or a thin overlay
if additional strength is required.
Terminology
Flushing
Flushing is excess asphalt on the
surface caused by a poor initial asphalt
mix design or by paving or seal coating
over a flushed surface. Repair by blotting
with sand or by overlaying with
properly designed asphalt mix.
Terminology
Polishing
Polishing is a smooth slippery surface
caused by traffic wearing off sharp
edges of aggregates. Repair with
sealcoat or thin bituminous overlay
using skid-resistant aggregate.
Terminology
Rutting
Rutting is displacement of material,
creating channels in wheel paths.
It is caused by traffic compaction or
displacement of unstable material.
Severe rutting (over 2") may
be caused by base or subgrade
consolidation. Repair minor rutting
with overlays. Severe rutting requires
milling the old surface or reconstructing
the roadbed before resurfacing.
Terminology
Distortion
Shoving or rippling is surfacing
material displaced crossways to the
direction of traffic. It can develop
into washboarding when the asphalt
mixture is unstable because of poor
quality aggregate or improper mix
design. Repair by milling smooth and
overlaying with stable asphalt mix.
Other pavement distortions may be
caused by settling, frost heave, etc.
Patching may provide temporary
repair. Permanent correction usually
involves removal of unsuitable
subgrade material and reconstruction.
Terminology
Transverse Cracks
A crack at approximately right angles
to the center line is a transverse crack.
They are often regularly spaced. The
cause is movement due to temperature
changes and hardening of the
asphalt with aging. Prevent water intrusion and damage
by sealing cracks which are more
than 1/4" wide.
Terminology
Reflection Cracks
Cracks in overlays reflect the crack
pattern in the pavement underneath.
They are difficult to prevent and
correct. Thick overlays or reconstruction
is usually required.
Terminology
Slippage Cracks
Crescent or rounded cracks in the
direction of traffic, caused by slippage
between an overlay and an underlying
pavement. Slippage is most likely to
occur at intersections where traffic is
stopping and starting. Repair by
removing the top surface and
resurfacing using a tack coat.
Terminology
Longitudinal Cracks
Cracks running in the direction of traffic
are longitudinal cracks. Center line or
lane cracks are caused by inadequate
bonding during construction or reflect
cracks in underlying pavement. Longitudinal
cracks in the wheel path indicate
fatigue failure from heavy vehicle loads.
Cracks within one foot of the edge are
caused by insufficient shoulder support,
poor drainage, or frost action. Cracks
usually start as hairline or vary narrow
and widen and erode with age.
Without crack filling, they can ravel,
develop multiple cracks, and become
wide enough to require patching.
Terminology
Block Cracks
Block cracking is interconnected cracks
forming large blocks. Cracks usually intersect
at nearly right angles. Blocks may
range from one foot to approximately
10' or more across. The closer spacing
indicates more advanced aging caused by
shrinking and hardening of the asphalt
over time. Repair with sealcoating during
early stages to reduce weathering of the
asphalt. Overlay or reconstruction required
in the advanced stages.
Terminology
Alligator Cracks
Interconnected cracks forming small
pieces ranging in size from about 1" to
6". This is caused by failure of the
surfacing due to traffic loading (fatigue)
and very often also due to inadequate
base or subgrade support. Repair by
excavating localized areas and replacing
base and surface. Large areas require
reconstruction. Improvements in
drainage may often be required.
Terminology
Patches
Original surface repaired with new
asphalt patch material. This indicates a
pavement defect or utility excavation
which has been repaired. Patches with
cracking, settlement or distortions
indicate underlying causes still remain.
Recycling or reconstruction are required
when extensive patching shows distress.
Street Evaluation
Woodhavens Drive
W2 (middle)
10 -- Excellent
newly paved
Street Evaluation
Timber View Drive
T2 (middle)
10 -- Excellent
recently paved
Street Evaluation
Yew Court
Y
6 -- Good
slight to medium raveling
some cracks (mostly patched)
one pothole
Street Evaluation
Clearbrook Court
Cl
6/5 -- Good to fair
mild cracking
raveling
Street Evaluation
Ivy Court
I
6/5 -- Good to fair
some cracks, most filled
Street Evaluation
Timber View Drive
T3 (bottom)
6/5 -- Good to fair
light cracking
light raveling
Street Evaluation
Shagbark Court
Sh
5 -- Fair
longitudinal and transverse cracks
some raveling
Street Evaluation
Scenic Point
Sc
5 -- Fair
light raveling
light alligator cracks
few longitudinal cracks
some transverse cracks
Street Evaluation
Lake View Point
L
5 -- Fair
patched cracks
light alligator cracks
beginnings of slippage at edges
Street Evaluation
Spiria Court
Sp
5 -- Fair
longitudinal and transverse cracks
slight raveling (along center)
Street Evaluation
Edgewood Court
EN (north end)
5 -- Fair
profuse cracks
some raveling and potholes
Street Evaluation
Edgewood Court
ES (south end)
5 -- Fair
heavy and prevalent transverse cracks
some longitudinal cracks
Street Evaluation
Cedar Court
CE (east end)
5 -- Fair
mild raveling
some transverse cracking
numerous patched cracks
Street Evaluation
Juniper Lane
J
5/4 -- Fair
several transverse cracks
several longitudinal cracks
some alligator and block cracks
mild raveling
Street Evaluation
Woodhavens Drive
W1 (entrance up to Timberview)
5/4 -- Fair
some raveling (along center)
slight alligator cracks
several longitudinal cracks
large patches (2007)
Street Evaluation
Cedar Court
CW (west end)
5/4 -- Fair
mild to severe raveling
transverse cracks
longitudinal cracks
block cracks
Street Evaluation
Autumn Court
A
No longer rated as a 4 street
Under renovation with new hot asphalt replacement of center line.
New CRF Sealant application will be competed in September 2009.
Street Evaluation
Timber View Court
T1 (top)
4 -- Fair
mild to severe raveling
longitudinal and transverse cracks
two lines of longitudinal cracks
with severe raveling
Street Evaluation
Woodhavens Drive
W3 (lower end)
4/3 -- Fair to poor
raveling
longitudinal and transverse cracks
alligator cracks
Street Evaluation
Palm Court
Pa
4/3 -- Fair to poor
mild to severe raveling
longitudinal cracks (some parallel)
transverse cracks
medium alligator cracks
disintegration along edges
Street Evaluation
Persimmon Place
Pe
4/3 -- Fair to poor
some block cracking
mild to severe alligator cracks
some transverse cracks
some longitudinal cracks
mild to severe raveling
Credits
Evaluated by Jeff Kohl, Bloomington City Engineer
Photographs and Notes by Anna Groebe and Ben Groebe