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Terms in this set (62)

i) Alligator cracking - cracks that are interconnected to form a series of small blocks in the pavement similar to alligator skin. The usual causes are excessive heavy loads over unstable subgrade and base layers.
ii) Longitudinal and Transverse Cracks - various cracks occur in the longitudinal or transverse of the road reasons include aging of seal (becomes brittle and from overlays over a poorly repaired crack on the old pavement.
iii) Joint Cracks -this occurs where the pavement has been contracted separately or cut and reinstated. Described as separation of the joint between and pavement and shoulder or lane or trench.
iv) Rutting - These are channelised depressions which develop in wheel tracks of a flexible pavement. They result from consolidation or lateral movement under load in one or more of the underlying layers or by displacement in the asphaltic concrete layer.
v) Corrugations and Shoving - normally occur on the edge of a road and due to instability of the base layer causing displacement of the layer from traffic loads. Probably caused by poor compaction of the layers.
vi) Scabbing - loss of particles from the surface sealing chip or asphaltic concrete layer. Due to lack of interlock between the bitumen and chip because of either traffic on seal too early, to cool for sealing or lack of bitumen.
vii) Flushing/Bleeding - where bitumen has risen to the surface and covered or partially covered the chip/aggregate. This occurs when there is excessive binder application rate or the bitumen penetration grade is susceptible to high temperatures.
viii) Potholes - occur where the pavement surface is not longer water proof and water gets through cracks and small areas of seal break out. This tends to happen where the sealed surface is aged and become brittle.
ix) Edge Break - disintegration of the edge of the road carriageway. Causes include infiltration of water and traffic loads on the edge of the seal.