What Are the Best Practices for
Seismic retrofitting is used for improving the capacity of an existing structure to resist seismic activity or gourd motion like earthquakes. There are different methods for increasing the lateral strength of a building or structure that you will understand in this article.
Consulting a reputable retrofitting contractor like soft story retrofit is essential for improving the seismic strength of your building. Take a look at the best practices of seismic retrofitting for better seismic performance.
Tips for Seismic Retrofitting
There are several techniques for seismic retrofitting. Here are some of the best practices, both including conventional and non-conventional techniques.
The conventional techniques of seismic retrofitting are useful for the adverse effects of construction and design. There are mainly three conventional techniques:
- Adding Shear Walls
- Adding Steel Braces
- Adding Infills
Now, let’s discuss them one by one in detail to understand the conventional approach clearly.
Adding Shear Walls
Adding shear walls can help to improve the lateral strength of the reinforced structure or building. It is one of the most popular and simplest methods for better seismic performance. This method is best suitable for non-ductile reinforced concrete frame buildings.
The addition of shear walls can be done by precast or cast in place concrete elements. It’s always preferable to add the shear walls on the exterior side to avoid interior moldings. However, it can change the appearance of the building and window layouts.
Adding Steel Braces
Likewise, adding shear walls, another method for improving the strength of the concrete building, is by adding steel braces. There are some extra benefits of steel braces than other seismic retrofitting methods. Here are the potential advantages of adding steel braces:
- It increases both strength and stiffness of the concrete building.
- It’s a great method for natural light.
- Cost is less in comparison to other methods.
- Weight is less as compared to adding shear walls.
The steel braces method can be used both for steel and concrete structures. So, this is the preferable method for seismic retrofitting purposes.
Adding Infill Walls
An economical method to increase the strength of frames is by adding infill walls. This method is also useful for reducing the drift of existing frames. However, the method can result in a failure of the column strong masonry infill is added.
So, it’s important to ensure that the strength of infill walls is appropriate. With proper selection of strength of the infill walls, it’s possible to prevent the premature flexural failure of the column.
Over the years, several non-conventional techniques have evolved. Among different methods, we will only discuss the following two:
- Seismic Base Isolation
- Supplemental Damping Devices
These techniques are still in their infancy stage. However, you will be able to understand how these methods can be useful in seismic retrofitting.
Seismic Base Isolation
The seismic base isolation method works with a different philosophy that this method is concerned about reducing the seismic forces. It is one of the most powerful techniques in controlling passive structural vibration.
This method can decrease the chances of damage to the structure by reducing the seismic loads. The building can be serviceable even during construction. Again, the superstructures don’t need any reinforcement in these techniques. However, it can be expensive and challenging to implement efficiently.
Supplemental Damping Devices
Finally, supplemental damping devices can be useful in resisting seismic force. Installing viscous damper or visco-elastic dampers is a great way to resist seismic loads. Other components of supplemental damping devices are frictional dampers and hysteretic dampers.
Hopefully, the above information has helped you understand the best practices for seismic retrofitting. If you want to improve the lateral strength of any building or structure, it’s important to consult an experienced professional engineering solution, for that matter.