Structural Strengthening & Concrete Repairing

Structural Strengthening & Concrete Repairing

Repairing and strengthening concrete structures is an essential requirement in today’s construction industry. Concrete structures can suffer damage due to various factors, including:

1. Poor Quality of Concrete/Workmanship During Construction: Inadequate mixing, curing, or improper construction practices can lead to concrete defects.
2. Corrosion-Related Deterioration: Exposure to harsh environments, such as saltwater or chemical exposure, can cause corrosion of reinforcing steel within the concrete.
3. Carbonation: Carbon dioxide from the atmosphere reacts with the concrete, reducing its alkalinity and compromising its durability.
4. Freeze-Thaw Damages: Cycles of freezing and thawing can cause cracks and spalling in concrete.
5. External Impacts: Accidental impacts, seismic events, or heavy loads can damage concrete elements.
6. Design-Related Issues: Flaws in the original design may lead to structural weaknesses.
7. Environmental Factors: Humidity, temperature variations, and exposure to aggressive chemicals affect concrete durability.
8. “Halo of Anodic Ring” Effect: A localized corrosion phenomenon around embedded metals.

There are various repair techniques and materials exist to overcome deficiencies mentioned above. Selection of suitable methodology depends up on many factors such as:

• Limited access to work areas
• Time limit (Duration available to complete the repair works)
• Expected life span  of the structure after repair, (i.e., minimum repairs to be done if the building is to be demolished in few years)
• Weather implications
• Cost implications, etc.…

Polymer modified, shrinkage compensated concrete (Micro-concrete) and repair mortars are most used for repairs though various materials are there in use for repair program. Epoxy resin-based repair mortars are equally important where there is time constraints, and added strength requirements are in demand, though this is comparatively expensive.
Specific repair tasks which we carry out include:

• Concrete repair for columns, beams, slabs, and walls.
• Spalled column, wall, and beam repairs.
• Column and beam jacketing.
•  Reinstating spalled concrete slabs.
• Strengthening post-tensioned slabs and other structural members.
• Freezer room floor repairs.
• Heavy-duty concrete floor and pathway repairs.
• Repairing pavements using epoxy terrazzo (ET) slurry.
• Flyover repairs.
• Box girder and bridge repairs using composite sections.
• Joint sealant filling with polysulfide, polyurethane, or coal tar sealants.
• Injection grouting to fill cracks in concrete structures.
• Installation of carbon fiber plates or fabric for column, beam, and slab strengthening.
• PU injection to stop water tank and water-retaining structure leaks.
• Repairing floor slab cracks using low-viscosity epoxy resin via the ponding method.