Common Types of Injection Grouting

1. Cementitious Grouting

• Material: Fine cement-based grouts, sometimes with additives like non-shrink agents
• Applications: Large voids, honeycombs, masonry cracks, baseplate grouting
• Limitations: Not suitable for very fine cracks (<0.2 mm) or structures subject to movement

2. Polyurethane (PU) Grouting

• Material: Hydrophobic or hydrophilic polyurethane resins
• Applications: Active water leak sealing in tunnels, basements, lift pits, and water tanks
• Features: Rapid reaction with water to form foam or gel; highly effective for leak arrest

3. Epoxy Grouting

• Material: Low-viscosity epoxy resins
• Applications: Structural bonding of fine cracks in concrete beams, columns, slabs, foundations
• Features: High strength, excellent adhesion, and chemical resistance

4. Acrylic Grouting

• Material: Acrylic gels
• Applications: Soil stabilization, curtain grouting behind tunnel linings, waterproofing underground structures
• Features: Very low viscosity, deep penetration, flexible sealing

5. Microfine Cement Grouting

•  Material: Ultra-fine cement particles
• Applications: Soil injection, structural voids, foundation grouting
• Features: Improved penetration compared to standard cement grout

Application Procedure

• Inspection and Diagnosis

• Identify the type and extent of cracks or voids

• Determine the appropriate grouting material based on site conditions

• Surface Preparation

• Clean surface and remove loose debris, dirt, paint, or coatings

• Drilling and Installation of Packers

• Drill holes at specific intervals along the crack or void

• Install injection packers (nipples or ports) to direct grout into the structure

• Injection

• Use a grout pump to inject the material at controlled pressure

• Start from the lowest point (in vertical applications) or one end (in horizontal applications)

• Monitor flow and ensure full penetration

• Curing

• Allow appropriate curing time as per manufacturer specifications

• Remove packers and seal holes if necessary

• Finishing

• Grind or finish the surface for aesthetic or functional requirements

Advantages of Injection Grouting

• Minimally invasive repair technique

• Restores structural strength without demolition

• Effective waterproofing of active leaks

• Compatible with different substrates—concrete, masonry, rock, soil

• Extends service life of deteriorating structures

• Reduces long-term maintenance costs

Typical Applications

• Cracks in slabs, columns, beams, walls, tunnels, and dams

• Basements, water tanks, swimming pools, and podiums for waterproofing

• Industrial floors with dynamic loading

• Bridges and flyovers with movement joints or cracks

• Heritage structure restoration where conventional repairs are not viable

• Soil stabilization and curtain grouting in underground works