Working With Concrete Under Water. How Does That Work?

  Armin Maiwald mixing cement Copyright: ibac First Armim Maiwald showed what concrete consists of and how it is mixed.

Who doesn’t know them – the stories from the „Sendung mit der Maus“, or Show with the Mouse? Originally designed for young children, these stories now even have many adult fans! So it was a great honor, when in September the ibac received a special visit from Armin Maiwald, the co-inventor of the Show with the Mouse, and his film crew. A new story for the show was to explain how pouring concrete under water could work. Since this could hardly be filmed at a big construction site, the procedure was simulated with a water-filled aquarium at ibac. But first, Armin Maiwald explained what the different components of concrete even are. In the process he created a concrete cube. After the formwork was stripped the next day, Maiwald showed that the concrete was set, or hardened, by standing on top of the cube.

Next it was off to the water-filled aquarium. Its floor was covered in sand and Lisa Janissen, a member of the academic staff at the institute, poured the liquid concrete into it with the help of a screw pump. On the following day the water was pumped out of the aquarium and here again the team was able to demonstrate that the concrete had hardened by standing on it. Armin Maiwald’s film crew was thrilled how easy it was to show the process on camera.

The exact air date of the under water concrete story has not yet been determined. One thing is certain, however: It was great fun for us to have an active part in creating a new story for „Sendung mit der Maus!“

  Lisa Janissen showed how the conrete was placed underwater. Copyright: ibac Lisa Janissen showed how the concrete was placed underwater with a screw pump.   The water was pumped out of the aquarium; the concrete had hardened. Copyright: ibac The next day, the water was pumped out and the film crew was able to show the hardened concrete on film.