Concrete lifting refers to pumping grout below settled concrete to raise it back up. CJGeo specializes in using polyurethane grouting to stabilize and lift settled or unstable concrete slabs and structures.

Polyurethane grouting differs from mud jacking in that the expansion of the polyurethane foam is what generates lift, as opposed to the mechanical force of the pump. Polyurethane grout is much lighter than cement grout. This reduces the likelihood of future settlement.

Concrete lifting with geotechnical polyurethane is exceptionally clean. CJGeo has performed concrete lifting with polyurethane in many food grade environments with zero downtime.

Polyurethane grouts expand upon injection with controlled upward pressure to lift and level sunken structures. This technique is often used in combination with polyurethane compaction grouting to fully stabilize soils below structures.

Typical Applications

Concrete lifting using polyurethane grouts can fix settlement in two ways. The most common method is injecting grout immediately below or adjacent to the slab or structure. Shallow grouting is sufficient in applications where the underlying soils are stable, or the consequences of resettlement are low. If a higher factor of safety is required, or if the underlying soils are known to be inadequate, grout can also be injected into the adjacent soils. Polyurethane grouting in soils behaves just like compaction grouting using low mobility grouts.

Polyurethane grouting in soils is coupled with DCP (Dynamic Cone Penetrometer) testing to quantify the conditions of existing soil before and after polyurethane grouting. Depending on the conditions encountered during DCP testing, grout planning is done prior to injection to achieve target results.