International Catalogue

Basic Knowledge of Fastening Technology
Basic Knowledge of Fastening Technology
Fundamentals
Building materials
● Concrete
Concrete
The substrate and its quality is decisive for selection of the fixing: The building
material and anchor base. A differentiation is made between concrete, masonry
and panel building materials.
Concrete is made from a mixture of cement, additives and water. The main properties
of concrete are:
▪ High compressive strength, but only low tensile strength (≈ 10% of the
compressive strength).
▪ Insertion of reinforcement steel (individual bars or mats) increases the tensile
strength (steel + concrete = reinforced concrete)
▪ Easily reproducible, because regulated by standards and thus it represents an ideal
anchor base.
Concrete is mainly divided into two categories:
standard concrete and lightweight concrete: While standard concrete contains gravel,
lightweight concrete comprises additives like pumice, expanded clay or Styropore, usually
with lower compressive strength. Among other things, this leads to unfavourable conditions
for anchoring fixings.
The magnitude of the performance of a heavy-load fixing depends, among other
things, on the compressive and tensile strength of the concrete. This is indicated by the
numbers in the abbreviations: e. g., the most frequently occurring concrete strength is C
20/25 for a cube compressive strength of 25 N/mm².
Concrete strength classes in different countries
Country Specimen Dimensions 1)
Concrete strength class Unit Standard
[cm]
China Cube 15 x 15 x 15 C15, C20, C25, C30, C35, C40, C45, C55, C60 N/mm 2 GBJ 10-89
Denmark Cylinder 15 x 30 5, 10, 15, 25, 35, 45, 55 N/mm 2 DS 411
Germany Cube 15 x 15 x 15
C12/15, C16/20, C20/25, C25/30, C30/37,
C40/50, C45/55, C50/60
N/mm 2 DIN 1045-1
France Cylinder 16 x 32
C20/25, C25/30, C30/37, C35/45, C40/50,
C45/55, C50/60
N/mm 2
BS 1881:
Great Britain Cube 15 x 15 x 15 C25/10 N/mm 2 Part 116
15 x 15 x 15
Italy
Cube 16 x 16 x 16 C12/15, C20/25, C30/37, C40/50, C50/60 N/mm 2 ENV 206
20 x 20 x 20
Japan Cylinder 10 x 20 ≧15 N/mm 2 JIS A 1108
Korea Cylinder 10 x 20 C 180, C 210, C 240, C 270, C 300 kg/cm 2 KS F 2405
The Netherlands Cube 15 x 15 x 15 B15, B25, B35, B45, B55, B65 N/mm 2 NEN 6720
Austria Cube 20 x 20 x 20
B5/B80, B10/B120, B15/B160,
N/mm
B20/B225, B25/B300, B30/350,
/
kp/cm
B40/B500, B50/B600, B60/B700
ÖN B 4200
Sweden Cube 15 x 15 x 15
K8, K12, K16, K20, K25, K30, K35,
K40, K45, K50, K55, K60, K70, K80
N/mm 2 BBK 79
Switzerland Cube 20 x 20 x 20
B25/15, B30/20, B35/25, B40/30, B45/35,
N/mm
B50/40
SIA 162
non-reinforced:
HM-20, HM-25, HM-30,
HM-35, HM-40, HM-45, HM-50
reinforced concrete:
Spain Cylinder 15 x 30 HA-25, HA-30, HA-35,
N/mm 2 EHE
HA-40, HA-45, HA-50
Prestressed concrete:
HP-25, HP-30, HP-35, HP-40, HP-45,
HP-50
USA Cylinder 15 x 30 2000, 3000, 4000, 6000 PSI ACI 318
1)
Conversion: f Cylinder = 0.85 x f Cube, 20x20x20 ; f Cube, 15x15x15 = 1.05 x f Cube, 20x20x20
450