Institut für Massivbau und Baustofftechnologie (IMB) - Abteilung Massivbau

Stahlbeton- und Spannbetonbau

Dampf-Gas-Leckage durch Stahlbetonwände

Investigation of the leakage behaviour of reinforced concrete walls

The leakage behaviour of reinforced concrete walls is of decisive  importance for containments. Extreme temperatures well over the water boiling temperature accompanied by high internal pressures can occur during accidents. In case of cracks through the entire thickness of the containment wall, air or an air-steam mixture may be released.

So far corresponding knowledge about the leakage of air-steam-mixtures through cracks was missing world-wide. The aim of the project was to obtain experimental results of the leakage of air or air-steam mixtures through a representative wall section under simulated accidental conditions.

First of all an entirely new test set-up was designed in order to apply typical pressure, steam and temperature scenarios to the internal face of a representative wall element and to allow continuous recording of the leakage amounts at the external face during the entire test duration. Furthermore new specimens had to be developed, produced and tested

The special test set-up is capable of providing air as well as air-steam mixtures composed of pressurized air mixed with maximum 6.5 bar saturated steam and being superheated up to 250 °C. The test facility allows to adjust the crack width time dependent during the scenario. Therefore it is possible to determine the leakage through cracks with different average crack widths based on different underlying scenarios under realistic conditions.