亚洲综合香蕉在线视频Retrofitting is the process upgrading of the building systems or modifying something after it has been manufactured and also to make the building more resistant to seismic activity. it also refers that the addition of new technology to older systems.
亚洲综合香蕉在线视频After building initial construction and occupation the retrofitting building involves changing its systems or structure and improves the performance of the building.
it can help cut carbon emissions, make it cheaper and easier to run buildings and also contribute to poor ventilation and damp problems and also increase building resiliency, durability, and adaptability.
亚洲综合香蕉在线视频Rather than replacement of building it proves to be a better economic consideration and immediate shelter to problems.
Classifications Of Retrofitting:
亚洲综合香蕉在线视频There are two classifications of it such as;
Retrofitting of reinforced concrete structures &
Retrofitting of masonry structures.
Retrofitting Of Reinforced Concrete Structures:
亚洲综合香蕉在线视频There are several techniques are available for the reinforced concrete structures such as;
Jacketing Of Structural Members:
Fiber-reinforced polymer sheets are used by modern jacketing techniques and for enhancing the strength of deficient members that have much higher strength than steel.
For the strengthening of deficient structural members, there are various jacketing techniques are available such as;
亚洲综合香蕉在线视频By placing reinforcing steel rebar around its periphery and then concreting is widely adopted which is called concrete jacketing and this is for enlargement on existing structural members like column and beam. This method increases the member stiffness and its size.
With steel angles, channels and bands jacketing of columns and beams is done.
Fiber Reinforced Polymer Jacketing:
This is a modern technique for enhancing the strength and this technique is based on composite materials such as carbon and glass fiber reinforced polymer. Using these high strength sheets retrofitting of structures can be done with much ease by using this technique and because of high tensile strength composite materials are excellent options to be used as external reinforcing.
Addition Of Extra Structural Members:
Developing the strong alternative load path is another method and inclusion of reinforced concrete shear walls possibly in between the columns. This method requires less disturbance in the existing building and in this method only shear wall is added right from the foundation level.
Addition Of Energy Dissipation Devices:
The energy devices like shock absorbers this method is a highly effective approach in seismic retrofitting, these devices are installed in this method and in the field of seismic retrofitting energy dissipation devices has shown a great promise.
Retrofitting Of Masonry Structures:
To make the existing structure more resistant to seismic activity, soil failure or ground motion due to earthquakes the retrofitting of masonry structure is the modification of existing structure and these techniques are also applicable for other natural hazards like winds from and tornadoes, etc.
There are many techniques of masonry structures as given below;
Adding New Shear Walls:
For retrofitting of non-ductile reinforced concrete frame buildings and added elements can be precast concrete element and at the exterior of the building new elements are placed. It is not preferred in the interior of the structure.
Adding Steel Bracing:
亚洲综合香蕉在线视频When large openings are required it is an effective solution and potential advantages due to higher strength and stiffness and the amount of work is less.
亚洲综合香蕉在线视频For the passive building vibration control it is the most powerful tool and isolation of superstructure from the foundation is known as base isolation. Base isolation gives some advantages that isolate buildings from ground motion and lesser damage to the structure.
Mass Reduction Technique:
By removal of one or more stories this may be achieved and removal of mass will lead to a decrease in the period which will increase the required strength.
Wall Thickness Technique of Retrofitting:
By adding bricks亚洲综合香蕉在线视频 the existing walls of a building are added to certain thicknesses and the weight of the wall increases and it can bear more vertical and horizontal loads and also it is designed under special conditions.
Techniques Of Retrofitting:
Purposes Of Retrofitting:
There are following purposes of retrofitting such as:
To make building safer
For damaged buildings
Earthquake damaged buildings
For public safety
There are following advantages of retrofitting such as;
Better rental income
Higher sale price
Increase in labor productivity
Better return on investment
Improves building quality
Lower operational cost
Greater building durability
Improves indoor environmental quality.
亚洲综合香蕉在线视频There are following disadvantages such as;
Increase in dead load
High installation cost
If any indication of corrosion in the reinforcement this technique is not useable
Chances of corrosion is high
Bonding between concrete and steel plates
Production of dust causes health hazards to the public.