Analysis of OWSJ with Class 4 Sections (CISC)

[cameron737]

Problem: Bending Resistance of Class 4 Sections
Governing Code: CISC (Canada)
Question: How do I solve "j" (or Monosymmetric Constant)?

Involves: OWSJ with double angle chords singly-symmetric about the y-axis; class 4 sections

I have to analyze some OWSJs whose top & bottom chords were fabricated using class 4 sections. Some of them have panel points greater than 610mm so I am referred to S136 to determine the bending resistance of the members.

C3.1.2.1 - Lateral Torsional Buckling Strength
- requires the calculation of Fe (Eq. C3.1.2.1-6) which contains the variable "j" (not "J" - St. Venant). It is this lower case "j" that has me perplexed. (formula attached in word doc)

It has been a long time since I have had to do anything like this, and have not found any help in the office.

Any ideas?

 

[LOKSTR]

cameron737,

I assume that you are talking about hot rolled angles which are class 4.

You do not need to refer to S136 for class-4. Look at cl.13.3.3 of S16, you have an option to reduce the width of section and make it class 3 and then check for bending.

Hope this helps.