Stone compressive strength class
Bricks are divided into stone compressive strength classes (SFK) according to the respective standard ( DIN 105 , DIN 106 , DIN 4165 , DIN 18151 , DIN 18152 ). In combination with the masonry mortar, this results in the permissible compressive stress of the masonry .
The stone compressive strength class is specified without a unit. The smallest individual value (in N / mm²) must not fall below the value of the SFK. The mean value is 25% higher than the classified value.
| Stone compressive strength class (SFK) |
Mean value (min.) [N / mm²] |
|
||
| 2 | 2.5 | 2.0 | ||
| 4th | 5.0 | 4.0 | ||
| 6th | 7.5 | 6.0 | ||
| 8th | 10.0 | 8.0 | ||
| 10 | 12.5 | 10.0 | ||
| 12 | 15.0 | 12.0 | ||
| 16 | 20.0 | 16.0 | ||
| 20th | 25.0 | 20.0 | ||
| 28 | 35.0 | 28.0 | ||
| 36 | 45.0 | 36.0 | ||
| 48 | 60.0 | 48.0 | ||
| 60 | 75.0 | 60.0 |
Usual values
Sand-lime brick according to DIN 106 : SFK 12/20
lightweight concrete blocks according to DIN 18151-100 / DIN 18152-100 : SFK 2 to 20
aerated concrete according to DIN 4165-100 : SFK 2/4/6/8
brick according to DIN 105-100: SFK 4 / 6/8
Minimum requirements
Facing bricks : SFK > 16 facing
bricks : SFK > 10