What is RCC Column Jacketing?
RCC column jacketing is a structural strengthening technique where the existing column is enlarged by:
- Adding new longitudinal reinforcement
- Providing closely spaced lateral ties
- Encasement with high-quality concrete or micro-concrete
The old and new concrete act compositely, improving axial strength, flexural capacity, and seismic resistance.
It is widely used in residential, commercial, industrial, and infrastructure retrofitting projects.
When Is RCC Jacketing Preferred?
RCC column jacketing is recommended when:
- Additional floors or loads are introduced
- Columns do not meet current seismic standards
- Reinforcement corrosion or spalling is observed
- Construction defects (honeycombing, low reinforcement) exist
- Fire or impact damage has occurred
- Major strength and stiffness enhancement is required
Compared to lightweight solutions, RCC jacketing is preferred for substantial structural upgrades.
Key Design Considerations
Proper design ensures composite action and long-term performance. Engineers evaluate:
- Existing column size, reinforcement, and concrete strength
- Axial loads, bending moments, and seismic forces
- Required strength enhancement
- Jacketing thickness (typically 75-150 mm)
- Compatibility with beams, slabs, and foundations
- Compliance with IS 456, IS 13920, and IS 15988
Advantages of RCC Column Jacketing
- Significant increase in axial, flexural and shear capacity
- Improved seismic performance and ductility
- Proven and durable strengthening metho
- Long service life (20-40+ years with proper execution)
- Full compatibility with RCC systems
Limitations of RCC Column Jacketing
- Slight increase in column size
- Additional load on foundations
- Longer execution time than FRP Jacketing methods
- Requires skilled workmanship and strict quality control
Proper planning minimizes these challenges.
Applications of RCC Column Jacketing
- Commercial building retrofitting
- Seismic strengthening projects
- Industrial buildings with increased machinery loads
- Parking structures and basements
- Bridges, flyovers and public infrastructure