Pore-free lightweight concrete

When lightweight aggregate concrete is a type of lightweight concrete , which is characterized by voids between the rock grains.

Surface of a pore-like expanded clay lightweight concrete wall

For the production of pore-free lightweight concrete, aggregates are used that are mainly composed of grains of the same size. As a result, as many cavities as possible, so-called heap pores, are present between the individual rock grains. The amount of cement paste is measured so that the grains are covered with a thin layer of glue, but are only cemented together at the points of contact. Both dense and porous aggregates, such as expanded clay or pumice , can be used.

Pore-free lightweight concrete has good thermal insulation properties that can correspond to that of wood . The compressive strength of lightweight concrete with pore structure is roughly between 2 N / mm ² and 20 N / mm ² . It depends on the bulk density and the grain strength of the aggregate.

Bricks as well as prefabricated parts and wall panels are mainly made from pore-free lightweight concrete.

In the case of reinforced components, it should be noted that the gas-permeable concrete does not protect the reinforcing steel from corrosion. Appropriate measures, such as a coating of the reinforcement or the use of stainless steels, are therefore necessary.

literature

• Association of German Cement Works e. V .: Cement leaflet concrete technology B13. Lightweight concrete 2014
• W. Scholz: Knowledge of building materials. Werner Verlag, Neuwied 2007, ISBN 978-3-8041-5227-4 .
• G. Neroth: Wendehorst building materials science. Basics - building materials - surface protection. Vieweg + Teubner, Wiesbaden 2011, ISBN 978-3-8351-0225-5 .