The Braced Frame is a structured system designed to withstand wind and earthquake forces. Members in a braced frame are not allowed to sway laterally (which can be done using the shear wall or a diagonal steel section similar to a truss).
A pin connections are used to make beam-column joints & connection, it does not transfer moments.
Here we will learn about braced frames, structural bracing types, advantages & disadvantages of braced frames structure.
Introduction to Braced frame:
The braced framing is generally used for the development of metal and wooden buildings.
Beams and columns are estimated under the vertical loads, assuming that the bracing system helps all lateral loads.
It relies on the bracing system to move the lateral system to the foundation: horizontal and vertical bracing methods are used.
Types of Structural Bracing:
1. Chevron bracing:
The chevron braced configuration supports two braces framing into a beam from opposite directions.
It consists of three sub-connections as follows:
- Left Brace-to-Gusset Connection.
- Right Brace-to-Gusset Connection.
- Gusset-to-Beam Connection.
2. Single diagonal bracing:
Diagonally braced frame are better in vertical tension and compression on opposite sides of the frames, due to the bending effect.
3. Portal frame bracing:
It is a combination of struts and ties, which transfer air pressure from the upper parts of the truss to the support of the bridge.
Advantages of Braced Frame structure:
- Due to bracing, lateral story displacement, story drift, axial force and bending moment in columns reduces to a notable level.
- The braced frames resist the wind and seismic forces more than the non-braced buildings.
- It is cost-effective, easy to erect and flexible to design to get required strength and stiffness.
Disadvantages of braced frame structure:
- Altitude-dependent changes in seismic region.
- The length of the span is usually restricted to 40 feet when reinforced.
- Construction of these frames requires skilled labor.
Also read: RCC Framed Structure, Space Frame Structure & Moment Resisting Frame