A Braced Frame is a structural system which is designed primarily to resist wind

Wind

Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space...

 and earthquake

Earthquake

An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...

 forces. Members in a braced frame are designed to work in tension and compression, similar to a truss

Truss

In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...

. Braced frames are almost always composed of steel members.

Types of Braced Frame

Concentrically Braced Frames

Most braced frames are concentric. This means that, where members intersect at a node, the centroid of each member passes through the same point.

Concentrically Braced Frames can further be classified as either Ordinary or Special. Ordinary concentric braced frames (OCBFs) do not have extensive requirements regarding members or connections, and are frequently used in areas of low seismic risk. Special concentric braced frames (SCBFs) have extensive design requirements, and are frequently used in areas of high seismic risk. The purpose of the SCBF design requirements is to ensure adequate ductility (i.e., to stretch without breaking suddenly).

Eccentrically Braced Frames

Some braces are intentially designed to accommodate eccentricity in the connections. These frames are called Eccentrically Braced Frames, or EBFs. Because EBFs are highly ductile, they are permitted in areas of high seismic hazard.

See also

Structural Engineering

Structural engineering

Structural engineering is a field of engineering dealing with the analysis and design of structures that support or resist loads. Structural engineering is usually considered a specialty within civil engineering, but it can also be studied in its own right....

Earthquake Engineering

Earthquake engineering

Earthquake engineering is the scientific field concerned with protecting society, the natural and the man-made environment from earthquakes by limiting the seismic risk to socio-economically acceptable levels...

Buckling Restrained Braced Frame

BRBF

Buckling Restrained Braced Frame is a structural steel frame that provides lateral resistance to buckling, particularly during seismic activity.The BRBF is typically a special case of a concentrically braced frame...