Video: Watching this foam — made of high-density polyurethane — raise heavy concrete slabs so easily seems like magic to me. The system, called PolyLEVEL, it’s applied drilling a hole in the concrete and sticking the foam into it. The foam expands under the concrete pushing it up as if it was a hydraulic jack.
Amazing Foam Raises Heavy Concrete Slabs As If It Was A Hydraulic Jack
