Depending on the ingredients used to form the concrete used when building a dam, it can happen that the concrete inflates and puts enormous pressure on the damn.
In that case, they let the water out of the dam and use a diamond chain saw to cut it from the top till the bottom, in the middle of the dam. The concrete will then use this space to fill in and reduce it's pressure, so that the dam can be filled again.
Here is a german video showing this procedure for a dam in Switzerland.
In that case, they let the water out of the dam and use a diamond chain saw to cut it from the top till the bottom, in the middle of the dam. The concrete will then use this space to fill in and reduce it's pressure, so that the dam can be filled again.
Here is a german video showing this procedure for a dam in Switzerland.
https://www.20min.ch/story/10-tonnen-beton-werden-aus-mauer-...