Guidelines for Safety Inspection of Dams - Central Water Commission

A.2.10 Spall: A fragment, usually in the shape of a flake, detached
from a larger mass by a blow, by the action of weather, by
pressure, or by expansion within the large mass.
A.2.10.1 Small Spall: A roughly circular or oval depression, generally
not greater than 2 cm depth nor greater than 15 cm in any
dimension, caused by the separation of a portion of the
surface concrete.
A.2.10.2 Large Spall: May be a roughly circular or oval depression, or
in some cases an elongated depression over a reinforcing bar,
generally 2 cm or more in depth and 15 cm or greater in any
dimension, caused by a separation of the surface concrete.
A.2.11 Joint Spall: Elongated cavity along a joint.
A.2.12 Dummy area: Area of concrete surface which gives off a
hollow sound when struck.
A.2.13 Stalactite: A downward pointing formation, hanging from the
surface of concrete, shaped like an icicle.
A.2.14 Stalagmite: As stalactite, but upward formation.
A.2.15 Dusting: The development of a powdered material at the
surface of hardened concrete.
A.2.16 Corrosion: Disintegration or deterioration of concrete or
reinforcement by electrolysis or by chemical attack.
A.3 Textural Defects
A.3.1 Bleeding channels: Essentially vertical localized open
channel caused by heavy bleeding.
A.3.2 Sand streak: Streak in surface of formed concrete caused by
bleeding.
A.3.3 Water pocket: Voids along the underside of aggregate
particles or reinforcing steel which formed during the bleeding
period. Initially filled with bleeding water.
A.3.4 Stratification: The separation of overwet or over-vibrated
concrete into horizontal layers with increasingly lighter
materials towards the top: water, laitance, mortar and coarse
aggregate will tend to occupy successively lower positions in
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