Heavy concrete
According to EN 206, heavy concrete is concrete that has a target density of over 2600 kg / m³ when it is dry.
Aggregate
The high dry density is achieved through the use of heavy aggregates . These are predominantly barite ( barite predominantly BaSO 4 ), ilmenite (titanium iron stone predominantly FeTiO 3 ), magnetite (magnetic iron stone predominantly Fe 3 O 4 ) or hematite ( red iron stone predominantly Fe 2 O 3 ) or heavy metal slag (predominantly lead or chrome slag). Limonite , colemanite , boron frit , boron calcite or boron carbide are also used for radiation protection concretes .
use
Heavy concrete is used, among other things, as radiation protection concrete to shield against X-ray , gamma , neutron and electron radiation . Further shielding is then often no longer necessary.
Other applications are ballast weights, for example crane counter weights , bridge abutments , in ships or as weight stones .
In the construction industry, heavy concrete is used, among other things, to increase the weight of base plates lying in the groundwater and thus prevent the basement floors from floating up. Base plates made of normal concrete would have to be made thicker and, accordingly, embedded deeper in the ground or groundwater. The associated costs for lowering the groundwater are compared to the roughly ten times higher cubic meter price of heavy concrete.
Web links
- Heavy concrete / radiation protection concrete (PDF; 104 kB)
References and comments
- ↑ often also called dry bulk density
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↑ DIN EN 206 . January 2017.
- "Concrete in the oven-dry state with a bulk density of over 2,600 kg / m 3"
- “For heavy concrete, the density of the oven-dry concrete must be more than 2,600 kg / m 3. If the gross density is set as the target value, a permissible deviation of ± 100 kg / m 3 applies, unless otherwise specified. "