Buckling Lenght Factor
Buckling Lenght Factor
(OP)
Hi all
i have a question about buckling lenght factor for steel column.
i have Building which is 9 storys height with moment resistant frame(MRF) on one direction and bracing on the other direction both are for lateral loads resistance.
There is a column which is a part of the moment resiatnce frame and on the other direction it is supported by X bracing and a steel beam at floor level(shear connection)
so i have assumed buckling lenght factor for column in direction of X bracing to be 1.
and i calculated buckling lenght factor for the column in the direction of the moment resiatnce frame using Aligment charts.
The column is hinged on base. I got K=3.5!!
First question. Using K factor=1 for direction of bracing is ok?
Second Question, i do not feel ok by using Kfactor=3.5! in direction of moment resiatnce france because this will lead to extremely big section. so shall i assume K factor on MRF direction=2?
Thanks All
i have a question about buckling lenght factor for steel column.
i have Building which is 9 storys height with moment resistant frame(MRF) on one direction and bracing on the other direction both are for lateral loads resistance.
There is a column which is a part of the moment resiatnce frame and on the other direction it is supported by X bracing and a steel beam at floor level(shear connection)
so i have assumed buckling lenght factor for column in direction of X bracing to be 1.
and i calculated buckling lenght factor for the column in the direction of the moment resiatnce frame using Aligment charts.
The column is hinged on base. I got K=3.5!!
First question. Using K factor=1 for direction of bracing is ok?
Second Question, i do not feel ok by using Kfactor=3.5! in direction of moment resiatnce france because this will lead to extremely big section. so shall i assume K factor on MRF direction=2?
Thanks All






RE: Buckling Lenght Factor
Answer to second question: 3.5 sounds awfully high--did you use G = 10 for the pinned base? If so, your girder is probably not stiff enough, and the building would sway too much, anyway. A stiffer girder would be in order.
DaveAtkins
RE: Buckling Lenght Factor
I hope this helps!
RE: Buckling Lenght Factor
RE: Buckling Lenght Factor
yes i used G=10 for pinned base
Jike you are talking about AISC-ASD89 as a refrence for this K Factor for Inelastic buckling?
RE: Buckling Lenght Factor
Does the reduction factor equal to value fa/F`e?
i have diffrent grade of steel than A36 and A50 that are listed in the table, so what is the soure equation for values listed in the table?
Note:- i am using steel with Fy=275 MPa
RE: Buckling Lenght Factor
Yes, if I remember correctly, the reduction factor is fa/F'e.
RE: Buckling Lenght Factor