SCOPE:
To determine Efflorescence of Bricks.
Efflorescence is a crystalline deposit of salts that can form when water is present in or on brick, concrete, stone, stucco or other building surfaces. It has a white or greyish tint and consists of salt deposits left behind when water evaporates.
IS CODE:
IS: 3495 - 1992.
APPARATUS:
1) Glass tray of 180 x 180 x 40 mm of square shaped
2) 200 x 40 mm Dia for cylindrical shaped or square shaped.
PROCEDURE:
a) Five Bricks needed for Efflorescence.
b) Place the dish and add Distilled water of 25 mm to place the bricks vertically
c) Place the whole arrangement should be warm ( 20 to 30 ºC ) Until the Distilled water in the specimen is absorbed by the specimen
d) Cover the dish with suitable glass cylinder to avoid evaporation.
e) When the Distilled water has been absorbed and the bricks appear to be dry add some Distilled water to the dish.
f) Examine the bricks for efflorescence after the second evaporation and examine the results.
g) Report all results separately for each units.
SPECIFICATIONS:
The liability to efflorescence shall be reported as
‘nil’,
‘slight’,
‘moderate’,
‘heavy’ or ‘serious’
in accordance with the following definitions:
Nil - When there is no perceptible deposit
of efflorescence.
SIight - When not more than 10 percent
of the exposed area of the brick is covered
with a thin deposit of salts.
Moderate - When there is a heavier deposit
than under ‘slight’ and covering up to 50
percent of the exposed area of the brick
surface but unaccompanied by powdering
or flaking of the surface.
Heavy - When there is a heavy deposit of
salts covering 50 percent or more of the
exposed area of the brick surface but
unaccompanied by powdering or flaking of
the surface.
Serious - When there is a heavy deposit
of salts accompanied by powdering and/or
flaking of the exposed surfaces.
✓ The bricks when tested in accordance with the procedure laid down in Is 3495(part 3) the rating of efflorescence shall not be more than "moderate" up to class 12.5 and "slight" for higher classes.