PU injection grouting is a highly effective waterproofing technique that injects expanding polyurethane resin into cracks, voids, and joints in concrete structures. The low-viscosity liquid penetrates deep into hairline fissures under high pressure, then reacts with water or moisture to expand rapidly—often 10-20 times its volume—forming a flexible, closed-cell foam seal. This method ... https://shakuraconstruction.sg/pu-injection-grouting-singapore/