Upload
mhanif-ar
View
42
Download
16
Embed Size (px)
DESCRIPTION
Types of defect
Citation preview
ROAD DEFECTMOHD HANAFI BIN HASHIM
POLITEKNIK KOTA KINABALU
CROCODILE CRACK
Crocodile is interconnecting or interlaced cracking in a
road seal resembling the hide of a crocodile. Cell sizes canvary in size up to 300mm across, but are typically less than
150mm across.
CROCODILE CRACK
CROCODILE CRACK
CORRUGATION
corrugation are closely & regularly spaced transverse
undulations in the surface of a road,
Corrugations can occur in both sealed and unsealed
roads. They can be caused by inadequate stability of an asphalt surface or pavement or the compaction of the
base in wave form.
Crest to crest spacing is typically less than 2 metres.
CORRUGATION
CORRUGATION
CORRUGATION
CORRUGATION
DELAMINATION
Delamination is a failure mode that can occur in layered materials. With respect to roads it refers to the loss of large discrete area of the wearing course layer, usually in conjunction with a clear delineation of the wearing course from the layer below.
Possible Causes
Inadequate cleaning or inadequate tack coat before placement of upper layers.
Seepage of water through asphalt resulting in the breaking of the bond between the surface and the layer below.
A weak loose layer immediately under the wearing surface.
Adhesion of surface binder to the tyres of vehicles
DELAMINATION
DELAMINATION
DEPRESSION
In road engineering a depression is a localised
area of pavement surface that is slightly lower in
elevation than the surrounding pavement.
Depressions are most easily identifyable after rain
when they fill with water.
DEPRESSION
DEPRESSION
EDGE DROP OFF
An edge drop-off is road geometry defect where the vertical
distance from the edge of seal to the adjacent shoulder
exceeds acceptable limits.
Edge drop-offs generally occur when the road shoulder is worn, or there is inadequate strength of the pavement ay
the edge of the roadway. A significant edge drop-off can
make the transition between the road and its shoulder
challenging particularly for smaller vehicles, and this may
result in a loss of control for the vehicle.
EDGE DROP OFF
EDGE BREAK
An Edge Break is a broken or irregular edge of a road
wearing surface.
Edge breaks generally occur when the road shoulder is worn,
there is inadequate strength of the pavement at the edge if the roadway or water enters the pavement through the
shoulders. Significant edge breaks coupled with edge drops
can result in tyre damage.
EDGE BREAK
POTHOLE
A pothole is a hole in a road pavement, frequently rounded in
shape, resulting from the loss of pavement material under
traffic.
A pothole is created by the interaction between water and
traffic. Inadequate drainage alongside the road shoulder can
result in water entering underneath the pavement during
prolonged periods of rain. This weakens the pavement's subsoil
resulting in fatigue failure, or cracking, due to the flexing of the
pavement under vehicular loading.
These cracks in the pavement surface thereby provide another
entry for water and exacerbate the weakening of the
pavement's sublayers.
POTHOLE
RAVELLING
Ravelling is the progressive disintegration of a (road)
pavement surface through loss of both binder and
aggregate.
Water on the pavement is the primary cause for the loss of
the binder, while vehicular traffic gradually ravels away
the aggregate which has been loosened due to binder
loss.
RAVELLING
RAVELLING
RUTTING
Rutting is the longitudinal vertical deformation of a pavement
surface in a wheel path, measured relative to a straight edge
placed at right angles to the traffic flow and across the wheel
path, with a length/width ratio greater than 4:1.
A single instance of rutting is called a rut or wheel rut. Large ruts
can hold enough water to result in vehicles aquaplaning in wet
weather.
RUTTING
RUTTING
RUTTING
RUTTING
SHOVING
Shoving is the deflection and bulging of the road surface
generally parallel to the direction of traffic, and/or horizontal
displacement of surfacing materials. Shoving is typically caused by braking, accelerating or turning vehicles.
There are a number of factors that can make roads more
susceptible to shoving, including;
inadequate pavement strength or thickness
poor bonds between pavement layers
lack of containment of the pavement edge
SHOVING
SHOVING
SHOVING
COMPILATION
POLISHED
BLEEDING
Bleeding is the partial or complete immersion of aggregate into the bituminous binder causing low texture depth and inadequate skid resistance.
pavement surface defect in which binder is near the top of the aggregate particles. There is minimal surface texture. In severe cases the bitumen covers the aggregate.
Causes
BLEEDING occurs when the available void volume in a seal is insufficient to accommodate the volume of bitumen, aggregate fines and other detritus present.
BLEEDING
BLEEDING
REFERENCES
http://www.lgam.info
http://www.pavementinteractive.org/category/pavement-management/pavement-
distresses/flexible-pavement-distress/