Waterproofing Walls within the Structure Interior
Negative side waterproofing is applied from inside the structure to block water intrusion caused by cracks, porosity, or concrete defects. This method is essential when external access is limited, such as with basement walls, tunnel joints, cracked pipes, or internal burst points. It provides a targeted solution for sealing from the interior and can be carried out using three different types of sealants.
Polyurethane Injection for Waterproofing
Polyurethane is a liquid sealant used to stop water leaks, fill gravel pockets, and seal cracks and joints in concrete. It is injected under pressure into voids, where it expands upon contact with water to completely seal the damaged areas. The process requires a specialized machine to control injection pressure for precise application.
Injection of Acrylic Hydrogel
Acrylic hydrogel is a flexible, water-based resin that gradually forms a membrane-like barrier around structural elements, effectively preventing water ingress. The injection process uses a specialized dual-component machine designed for waterproofing infrastructure exposed to constant moisture and humidity. During application, high pressure ensures deep penetration into even the finest cracks in the concrete. This method is referred to as dual-component injection due to the material’s composition—two components that chemically react and solidify upon contact. The resulting solid can also be used in dry environments.
Injection of Cement Grout
An additional material used for waterproofing by injection is cement grout - a thick fluid material based on cement, sand and a polymer that is injected into special areas such as voids in concrete, for filling segregation areas (retaining walls), anchors and cracks in concrete. The material is noted for its high flexibility, making it useful for dynamic fissures. It also possesses a fast expansion property, filling the crack while maintaining structural strength.
Waterproofing by Injection:
How is it Done?
Before starting the waterproofing process, leak sources must be identified using a thermal camera for accurate detection. This is followed by a detailed mapping of the area, including marking the cracks, determining their size and depth, examining the concrete thickness, and defining the appropriate work process. Once the assessment is complete, holes are drilled into the concrete at strategic angles to allow for the insertion of injection nozzles or nipples, ensuring effective filling of the cracks.