Michael Wehrli
Bibliographic info:
13th International BUILDAIR Symposium, 2-3 June 2023, Hannover, Germany

I would like to report on lessons learned in the field regarding two measurements at a special, particularly airtight and unusual building: A "concrete shell for CO2 storage in recycled concrete aggregates". 

Not only the building and its use for the permanent storage of CO2 in demolition concrete was unusual, but also measuring the building as such was an “unusual” experience. The fan, for instance, was installed horizontally at a height of approximately 7m above ground in a wood-beamed ceiling. While concrete walls and floors provided for strong airtightness on four sides, the front side was covered with nothing more than a reversible heavy PVC tarpaulin to ensure airtightness. Channel rails on each side kept the tarpaulin in place. Part of it was spread out on the concrete floor and weighted down with about 5 tons of recycled granulate. During the first measurement we thus hoped that the design would be permeable while ensuring the highest possible airtightness. Nevertheless, we weren’t really certain about the results. It was for this reason that I made some mistakes during pressure build-up and noticed only in hindsight that my mistakes had had an astonishing effect – at least to some degree.  

I conducted the second measurement with Joachim Zeller. This time it was well-prepared and we were able to avoid the mistakes I had made with the first measurement … 

For further information please contact Michael Wehrli at: michael@wehrli-online.de