Retrofitting is a technique that is used to increase the lifespan of a structure. In retrofitting process, the structure is treated to increase its durability of the structure.
In simple terms, retrofitting is a method to rectify all the defects and make the structure fully functional for which it was intended.
As per requirement, various types of retrofitting are used. Here, I have listed types of popular retrofitting methods.
- Preservation retrofitting
- Rehabilitation retrofitting
- Restoration retrofitting
- Reconstruction retrofitting
Table of Contents
1. Preservation Retrofitting
The main aim of this type of retrofitting is to maintain the originality of the structure.
The structure is repaired without altering its integrity. There is no change in material and value.
2. Rehabilitation Retrofitting
When the structure becomes useless as per the current requirement from the perspective of functionality then rehabilitation retrofitting is used.
Normally old buildings become useless as per current requirements, hence rehabilitation retrofitting is used.
3. Restoration Retrofitting
Structure deteriorates its strength over a period of time. Structure loses its strength, aesthetics as time passes.
Restoration retrofitting is used to bring back structure to its original form.
4.Reconstruction Retrofitting
When a replica of the original structure is constructed, it is called reconstruction retrofitting.
Retrofitting Methods
There are various methods of retrofitting which is used based upon the purpose of their applications.
- Member Retrofitting
- Structure Retrofitting
1. Member Retrofitting
As the name suggests, in this type of retrofitting particular structural members are treated.
Let us discuss all types of member retrofitting.
1. Jacketing
In this method, extra strength is provided to existing structural members. A particular type of casing (jacket) is provided to the RCC members.
Generally, a fiber-reinforced plate or steel sheet is used to construct a jacket.
There are two methods of jacketing. In the first method, member jacketing is covered by cement or mortar. In the second method, the jacketing member is bound by an adhesive member such as epoxy.
2. Prestressing
Prestressing is a process in which prestressed wires are bound to the structural member.
Prestressing improves the load-carrying capacity of the structural members. This technique is costly and required skilled manpower.
3. Repaving
Replacing an old member with a new member is called repaving. This process is very tedious because an old member is completely replaced by a new structural member.
This process required skilled workers because extra precautions are needed while removing an old member and installing a new member.
2. Structure Retrofitting
Structure retrofitting involves the treatment of complete structure. These methods are also known as global methods because they cover complete structure.
1. Beam Addition
In this method, a secondary beam is provided between two primary beam.
The secondary beam absorbs the load and transfers it to the main beam then the main beam transfer the load to the column.
2. Shear Wall Addition
Shear wall is constructed between two columns. Shear wall made of reinforced cement concrete. It prevents the buckling of columns.
The higher load can be supported by constructing a shear wall between two struts. It enhances the structural integrity and overall efficiency of the building.
3. Support Point Addition
A support point system is used where the span of the beam is very large. These long-span beams are likely to be deflected. A support system is provided in such a way that it can limit the deflection of structural members.