Double Columns versus Single Columns with brackets

[jike]

We are doing preliminary work on a large steel frame building that will be divided into 4 quadrants by expansion joints. We are weighing the pros and cons of using double columns versus single columns with brackets.

Obviously, double columns take up more floor space, but are more capable of accomodating movements in both directions.

Anyone have any guidance?

 

[DaveAtkins]

Hi, jike,

If you were to use single columns with brackets, wouldn't you need to use teflon coated bearing plates? And you are correct, the detailing for movement in two orthogonal directions would be messy.

DaveAtkins

 

[slickdeals]

Are you in seismic country?

If you are, then you will need to account for building separations as well. I have previously used teflon pads on brackets which allowed for movement in 2 directions. It was a seismic detail, allowing upto 6" movement in either direction.

 

[jike]

Seismic Category C; Sds = .271, Sd1 = .165

 

[JAE]

I think cost-wise I've understood that double columns are cheaper than brackets with teflon - but I have to qualify that - I haven't performed cost checks recently to prove this.