Design of a WT shape
Design of a WT shape
(OP)
Can someone tell me what LRFD equations i can use for a WT shape subjected to axial and flexure with a lambda exceeding lambda r? Meaning that the shape is slender and must account for web local buckling. I am having trouble specifically finding the right equations especially for Mn to use in the H1-(a),(b) equations.






RE: Design of a WT shape
Check out Appendix B section3a."Unstiffened Compression Elements"
Calculate the design strength reduction factor Qs from section 3.a(d) "For stems of tees" using equations A-B5-9 or A-B5-10
Hope this helps
Warren
RE: Design of a WT shape
RE: Design of a WT shape
Sorry I haven't replied sooner, I was out of town.
As you can see by the lack of replies you have received,this is not an easy question.
This is the way I see it;
The WT8x15.5 is a slender member and must be designed per Appendex "B".
The equations that you are looking at in section F don't apply to this member.
The Design Flexure Strength is determine from Appendix B section 3a. which equals 0.9*Fy*Qs
Therefore the nominal flexural strength (Mn) = Fy*Sx*Qs
The Design Axial Strength (Fc) is determine from Appendix B section 3d equation (A-B5-15)
Therefore the nominal compressive strength (Pn) = Fc.
Now combine these under section H
Like I said, this is how I interpret it.
Warren
RE: Design of a WT shape