Difference between Moment Frame and Braced Frame

In braced frames, the columns and beams are often oriented orthogonally in both the elevation and the plan using a pinned connection that doesn’t transfer moments whereas moment frame is an arrangement of a frame that has hard connections between each of its constituent members.

The lateral loads are transferred to the foundation through the joints through the moment-resisting frame.

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Moment Frame Vs Braced Frame:

Moment Frame:

The Moment Frame is essentially an assemblage made up of beams and columns.

The assembly’s columns and beams are firmly attached to one another.

The stiff frame action with the formation of the Bending moment and Shear force in the members and joints provides resistance to the lateral forces in the Moment frames.

Moment frame primarily consist of a number of beams and columns with bolting and welding used to make the attachments.

Moment Frames has variety of forms as follows:

1. Ordinary Moment Frame (OMF).

2. Intermediate Moment Frame (IMF).

3. Special Moment Frame (SMF).

Braced Frame:

A structural design known as the Braced Frame is intended to withstand wind and seismic pressures.

The members of a braced frame may not swing laterally (which can be done using the shear wall or a diagonal steel section similar to a truss).

Pin connections are used to create the joints and connections between beams and columns.

Buildings made of metal and wood are frequently constructed using a braced frame.

Beams and columns are assessed under vertical loads with the assumption that the bracing system sustains all lateral loads.

The lateral system must be moved to the foundation using the bracing system, which employs both horizontal and vertical bracing techniques.

Bracing frames come in a variety of forms:

1. Concentric bracing.

2. Eccentric bracing.

What is the Difference Between Moment Frame and Braced Frame?

Moment-resisting frames directly resist lateral loads in the form of column moments and shear while the bracing receives the lateral load as an axial load.

There is no moment due to the pin connection; the bracing is either in tension or compression.

Braced Frame	Moment Frame
The beam-column joints are constructed using pin connections.	The link between beams and columns is rigid.
Moments are not transferred through the connection.	Through the link, moments are transferred.
The bracing system is responsible for transferring lateral loads to the foundation, and systems for horizontal and vertical bracing are employed.	To transport lateral loads to the foundation depends on the stiff connection.
Braced frame structure analysis is basic and easy.	It takes some effort to analyse the connection.
It doesn’t take a lot of work.	It requires a significant amount of labour.
Owing to the inexpensiveness, simplicity of fabrication, and analysis of the pinned connection.	They are expensive to build.
It provides the structure with effective stability.	The stabilizing technique is not as effective as braced frames.
Most steel and timber constructions are built using the braced frame approach.	Structures made with reinforced concrete automatically use moment-resistant frames.
Beams and columns are only investigated under vertical loads because it is assumed that the bracing system can support all lateral stresses.	Under axial loads and moments, beams and columns are examined.
There must be at least three vertical bracing planes for the plan to provide resistance in both directions against torsion about a vertical axis.	Every connection is stiff.
In comparison to moment-resistant frames, it is stiffer that have a lower deformation capacity.	Compared to braced frames, moment-resisting frames are less stiff that have a greater potential for deformation.

Conclusion:

When building structures are vulnerable to lateral loads like wind and seismic stresses, braced frames and moment resisting frames are both used.

Both braced frames and moment resisting frames serve the same purpose, which is to resist lateral loads and provide stability, but they each employ distinct techniques.