Polyurethane injection is a method used to repair and stabilize structures, particularly in cases of soil erosion or foundation issues. This process involves injecting a liquid polyurethane foam into the ground or cracks in a structure. Once injected, the foam expands and hardens, filling voids and providing support. This technique is often used in construction and civil engineering to prevent further damage and improve the integrity of buildings, roads, and other infrastructures. It is a quick and effective solution that minimizes disruption and can be completed in a short amount of time.