1. GENERAL QUALITY:
3. CLASSES OF BURNT CLAY BRICKS:
- The brick should be hand or machine moulded and made of admixture of suitable soils.
- The brick should be uniformly burnt, free from cracks and flaws such as nodules of stone, black coring and organic matter.
- Brick shall be uniform in colour and shall have smooth rectangular faces with sharp corners.
- Frog dimensions should be same for both modular and non modular size bricks.
- The Frog size should be either 10 or 20 mm for hand moulded brick of 90 mm or 70 mm height.
- No frog is provided for bricks of height 30 or 40 mm and for bricks made by extrusion process.
2. DIMENSIONS:
DIMENSION FOR MODULAR BRICKS
|
||
Length
(L)
|
Width
(W)
|
Height
(H)
|
190
mm
|
90
mm
|
90
mm
|
190
mm
|
90
mm
|
40
mm
|
DIMENSION FOR NON MODULAR BRICKS
|
||
Length
(L)
|
Width
(W)
|
Height
(H)
|
230
mm
|
110
mm
|
70
mm
|
230
mm
|
110
mm
|
30
mm
|
3. CLASSES OF BURNT CLAY BRICKS:
CLASS DESIGNATION
|
AVERAGE
COMPRESSIVE STRENGTH
|
|
N/mm2
|
Kgf/cm2
|
|
35
|
35
|
350
|
30
|
30
|
300
|
25
|
25
|
250
|
20
|
20
|
200
|
17.5
|
17.5
|
175
|
15
|
15
|
150
|
12.5
|
12.5
|
125
|
10
|
10
|
100
|
7.5
|
7.5
|
75
|
5
|
5
|
50
|
3.5
|
3.5
|
35
|
4. PHYSICAL PROPERTIES:
COMPRESSIVE STRENGTH
|
Compressive Strength of any individual brick
shall not be less than the minimum compressive strength for corresponding
class of bricks. (See table above)
|
WATER ABSORPTION
|
Shall not be more than 20% by weight up to class
12.5 and 15 % by weight for higher classes when the bricks are immersed in
water for 24 hours.
|
EFFLORECENCE
|
Shall not be more than moderate up to class 12.5
and slight for higher class.
|
