Surface scaling can be of two types. One is a relatively
thin scaling caused by improper finishing and curing operations. The
other is the scaling of non-air-entrained concrete caused by freeze-thaw
damage and the application of salts for snow and ice removal.
The materials and finishing and curing operations that cause dusting
of concrete surfaces also cause thin surface scaling. The procedures
used to prevent dusting will prevent this type of surface scaling.
Scaled concrete surfaces can be repaired by applying a thin resurfacing
of concrete properly bonded to the underlying old concrete. All defective
concrete must be removed from the surface, by scarifying or scrubbing
with hydrochloric acid, before applying the new concrete. A thin layer
of neat cement paste should be brushed into the damp surface of old
concrete just before the new concrete is placed to secure a good bond.
The new concrete is placed, finished, and cured by normal procedures.
Any relief joints present in the old concrete should be carried through
the new resurfacing.
To help prevent further surface scaling use a good concrete sealer
like
V-SEAL
after repair. If you choose not to effect repair,
V-SEAL
can slow further scaling effects.