Gable frame columns 1

[malikasal]

I am designing a gable frame with C100X50X1.5 Purlins and girts supporting a roof sheet and sidewalls, my question is will the purlins and girts brace the columns and rafters against buckling and LTB ????

ôIf you don't build your dream someone will hire you to help build theirs.ö

Tony A. Gaskins Jr.

 

[hokie66]

They brace the outside flange. In order to brace the inside flange, you need "fly braces", which are diagonal braces between the purlin/girt and the opposite flange.

 

[jayrod12]

It would brace against loading in one direction (i.e. gravity for roof beams and wind pressure for columns) they would not brace against uplift/suction forces.

 

[malikasal]

Thank you guys




ôIf you don't build your dream someone will hire you to help build theirs.ö

Tony A. Gaskins Jr.

 

[phuduhudu]

Just as an additional comment - they can only be relied on to brace the outside flange if there is a braced bay somewhere along the length that takes the horizontal forces back to the ground.

 

[malikasal]

phuduhudu : there is no vertical bracing in the longitudinal dimension because of some arch stuff, i had to use a fixed column system to resist the lateral loads .



ôIf you don't build your dream someone will hire you to help build theirs.ö

Tony A. Gaskins Jr.

 

[jayrod12]

I would prefer a moment frame over a fixed base assumption (depends on the situation) because are you truly getting fixed behaviour at the base of the column?

 

[malikasal]

I Totally agree with yoy Jayrod12 , but i had to choose between using a moment frame and making a moment connection to beam connected to column web with only 4.5 mm thickness, and a fixed base .

I think the fixed base assumption is way better than the moment frame in this case.



ôIf you don't build your dream someone will hire you to help build theirs.ö

Tony A. Gaskins Jr.