Steel Design
Steel Design
(OP)
Hello all,
I have a beam that has nodes equally spaced, creating smaller individual beams of equal lengths. When performing a steel design, I set the Ly (for the lateral torsional buckling equation) to the value of the spacing between each node. However, when performing the design, each beam (along the same line) are given different values for moment resistance and different values for the slenderness ratio. This is very strange. I am running the Canadian Code. I should also note than when inputting a Ly value that is large, all of the beams then have the same slenderness ratio and moment resistance.
Can someone please clarify?
Also, when do I use the parameters UNT UNB? Aren't Lz, Ly another name for UNT and UNB? Where is Lt used?
I have a beam that has nodes equally spaced, creating smaller individual beams of equal lengths. When performing a steel design, I set the Ly (for the lateral torsional buckling equation) to the value of the spacing between each node. However, when performing the design, each beam (along the same line) are given different values for moment resistance and different values for the slenderness ratio. This is very strange. I am running the Canadian Code. I should also note than when inputting a Ly value that is large, all of the beams then have the same slenderness ratio and moment resistance.
Can someone please clarify?
Also, when do I use the parameters UNT UNB? Aren't Lz, Ly another name for UNT and UNB? Where is Lt used?





RE: Steel Design
LZ and LY are the unbraced lengths used for axial compression (not bending) such as in a column or a brace. They are used in the kl/r slenderness.
RE: Steel Design
RE: Steel Design
I have one more questions,
How does Staad know to design a beam element as a BEAM (using parameters and equations for beams) or as a column (using parameters and equations of columns) or as axial tension members (using parameters and equations of tension members.) Do I have to specify the type of member it is or does Staad have its own way of finding out?
RE: Steel Design