Case 1
- Introduction
- Causes of Defects
- Good Practices
- Standards
- Maintenance and Diagnostics
- Remedial
- Similar Cases
- References
Remedial (see also Remedial)
Crack Repair Method
Repair Using Polyurethane (PU) Grouting
Polyurethane (PU) grouting is specially designed for providing water control in static joints or cracks in concrete structures. The grout material, when mixed with a certain amount of accelerator, will react with water or moisture and expand to form a tough, closed-cell rubber that is essentially unaffected by corrosive environment.
Polyurethanes are products of the petrochemical industry. They are very durable when exposed to external conditions and retain their gloss well. They can be obtained as elastomers, solid and rigid materials or flexible coatings. Major cracks or localized porous concrete can be repaired by this method.
In the application, PU reacts upon with the water in the slab and expands its volume and thus fills the cracks or pores in the slab. Therefore, it acts as a sealer over the cracks. The repairing process can be completed within half a day. Accelerator agents can be used to speed up the setting time of the grout. A finishing coat may be applied after the remedial work is completed.