In civil engineering, PU injection is used for ground improvement and slab lifting. By injecting expanding foam into the soil beneath a foundation, technicians can fill underground voids and compact loose dirt. This creates a solid base that can actually "lift" sunken concrete slabs back to their original level. It’s faster, cleaner, and often much cheaper than traditional mudjacking ... https://shakuraconstruction.sg/pu-injection-grouting-singapore/