KL/r > 200 for compression member 1

[eit09]

I have a V-brace that is an LL3x2x4x3 & receive the slenderness ratio error for compression. What values for r is Risa using? For this particular size I calculate 15'8" max length to satisfy the KL/r >200, but Risa is telling me its 14'-8". Also if I define the member using Euler buckling will risa use kl/r > 300?

Thanks!

 

[JoshPlumSE]

Take a look at the I and A values for the member in the member's double-click dialog. RISA uses r = sqrt (I/A).

When the member is defined as a tension only member (Euler members are a form of tension only members) then the program will look at L/r>300.

Both of these checks can be turned off, if desired, by going to Tools - Preferences - Solution and Results. Then Checking the box which says, "Allow KL/r>200, L/r>300 for LRFD, CAN steel design?"