Retrofitting of RCC structural members is carried out to regain the strength of deteriorated structural concrete elements and to prevent further distress in concrete. Strength deficiency of concrete structural members can be due to poor workmanship, design errors, and deterioration due to the aggression of harmful agents.
The retrofitting process shall start with investigation and diagnosis of cracks and then applying suitable retrofitting technique and compatible materials.
There are several techniques which are used to retrofit structural members such as section enlargement, external plate bonding, external post-tensioning, grouting, and fibre reinforced polymer composites. Based on the severity of the damage and required capacity to be regained, a proper retrofitting technique is specified and implemented
- Specify the performance requirement for the structural member that needs to be retrofitted.
- Then, set an overall plan from inspection phase to retrofitting method selection, the design of retrofitting structure, and execution of retrofitting work.
- After the finalization of plan, inspect the structural element that needs to be retrofitted.
- Evaluate the performance of the structural element based on the findings of the inspection work.
- Check whether the structural element fulfills performance requirements.
- If the structure does not fulfill performance requirements, and if continued use of the structure through retrofitting is desired, proceed with the design of the retrofitting structure.
- Select an appropriate retrofitting method.
- Specify materials to be used, structural specifications and construction method.
- Evaluate the performance of the structure after retrofitting and verify that it fulfills performance requirements.
- If it is determined that the retrofitting structure is capable of fulfilling performance requirements with the selected retrofitting and construction methods, implement the retrofitting work.