A new technology has been brought by the researchers towards lifting the concrete with the help of foam which is oddly satisfying. But there are essential characteristics which we should look for at the time of deciding what polyurethane should be used for lifting as well as levelling the concrete.
For this purpose, expansion is important but set up; cure time and adhesion should also be considered. If we talk about the reaction time, foam which reacts slowly is considered great for filling voids but not for raising concrete. If here are too slowly reacting materials then it can travel under as well as beyond the slab which you are trying to lift and then expand.
In this situation, you will have created a bridge of foam which is lifting the multiple slabs. Once this occurs, the only way in order to regain control over the slab is to cut with the help of layer of foam as well as attempt another lift again as the time and money is lost.
Polyurethane concrete demands for foam in order to lift concrete but it should not adhere to it. If we raising a slab of concrete along foundation, the foam can adhere to the foundation as well as lock up the slab into place.
For this reason, it is important to have foam which will set up with the tough exterior skin.