MSTE SET 6 Flashcards
The layer of the pavement which finally carries the load from the road.
SUB-GRADE
The top surface of a road structure which receives the traffic load and transfer it to the subgrade
BASE
Part of road structure which is immediately above the sub-grade and composed of stone boulders or superior soil.
SUB-BASE
An application of hot bitumen material given to the old surface to provide adhesion to the old and new road surface.
TACK COAT
A layer of stone chippings coat laid over a hot bitumen to make the surface water-proof.
PRIME COAT
A very thin surface applied over a bituminous pavement to make it impervious.
SEAL COAT
Cracks approximately at right angles to the pavement centerline. These may be caused by shrinkage or differential thermal stress of the asphalt concrete or maybe reflective cracks.
TRANSVERSE CRACKING
Cracks approximately parallel to the pavement centerline. These are caused by poorly constructed construction joints and shrinkage of asphalt concrete surface.
LONGITUDINAL CRACKING
Wearing way of the pavement surface caused by dislodging of aggregated particles and binder. This is usually a result of insufficient asphalt binder in the mix or stripping of asphalt from particles of aggregate.
RAVELING
Progressive disintegration of the surface between the wheel paths caused by dripping of gasoline or oil from vehicles.
DRIP TRACK RAVELING
The extruding of bitumen onto the pavement surface, causing a reduction in skid resistance. It is generally caused by excessive amounts of asphalt in the mix or low air voids content. It occurs when asphalt fills the voids in the mix during hot weather and then exudes out onto the surface of the pavement.
BLEEDING OR FLUSHING
Elevation differences between adjacent slabs at transverse joints. It is usually the result of pumping and is a major source of Portland Concrete pavement structure.
FAULTING
Localized upward buckling and shattering of the slabs at transverse joint or cracks. They can occur when transverse joints are filled with incompressible solid materials.
BLOWUPS
The breakdown or disintegration of slab edges at joints or cracks, usually resulting in the loss of sound concrete and the progressive widening of joint or crack.
JOINT SPALLING
A series of interconnected or interlaced cracks caused by fatigue failure of the asphalt concrete surface under repeated traffic loading.
ALLIGATOR CRACKING
Cracks forming large interconnected polygons, usually with sharp corners or angle. These cracks are generally caused by hardening and shrinkage of the asphalt and or reflection cracking from underlying layers such as cement-treated base.
BLOCK CRACKING
