Secondary Frames
Secondary Frames
The purlins, girts and eave struts
are secondary structural members.
Purlins are used on the roofs , while Girts are used on the walls, and Eave struts are used at the intersection of the sidewall.
Purlins are used on the roofs , while Girts are used on the walls, and Eave struts are used at the intersection of the sidewall.
Their main function is to support
the wall and roof panels.
They consist of prepunched cold- formed Z or C sections usually, 200mm in depth and 1.5 to 2.5mm in thickness.
They are bolted to rafters and columns.
They consist of prepunched cold- formed Z or C sections usually, 200mm in depth and 1.5 to 2.5mm in thickness.
They are bolted to rafters and columns.
Secondary members have two other functions:
1- Help in resisting part of the longitudinal loads that are applied on the building such as wind and earthquake loads.
2- Increase frame capacity by providing lateral bracing to the compression flanges of the main frame members.
1- Help in resisting part of the longitudinal loads that are applied on the building such as wind and earthquake loads.
2- Increase frame capacity by providing lateral bracing to the compression flanges of the main frame members.
