Concrete injection has been in use worldwide for several decades and is arguably the most common concrete crack repair method used for underground poured concrete structures and underground waterstopping in general. The two images above are typical commercial applications of concrete injection using polyurethane, also referred to as urethane, resins.
The image on the left is of a polyurethane injection of a poured concrete ceiling slab crack in a meat processing plant in Burlington, Ontario. Pressurized injection of polyurethane was required in order to repair the leaking cracks in the ceiling which were preventing the construction of a processing line below. The concrete cracks in the overhead slab leaked substantial amounts of water due to the daily powerwashing of another processing area located on the level immediately above.