Member stability check as per CISC( Canadian Steel code design CSA S16:2019) 1

[TTTKAO]

Hello All,

I am designing a building with Canadian steel design code CSA S16:2019. This building's analysis is following Simplified stability analysis method as per clause 8.4.3 by use of RISA 3D. For all the members designed by the software, I am wondering if i still need do member stability check as per chapter 9, my feeling is i should do stability check as well. Let's take building vertical brace for example, i will get a design force from software as per external force, and as per chapter 9, there is load requirement and displacement requirement due to building column stability which is supported by vertical brace. so i should consider the sum of these two forces together to design the vertical brace? May I ask who is familiar with CSA S16 code can help to verify my understanding ?

Thank you!

 

[dik]

I'm a bit of a dinosaur... I only use software to determine the member forces and design the members 'by hand'.

 

[KootK]

You always have to do the chapter 9 member stability checks. No getting around that.

The chapter 8 stuff will simply amplify the loads for which your members need to be designed. That's all.

The primary point of the chapter 8 provisions is to amplify loads for P-Delta effects. In practice, it usually pans out something like this:

1) Moment frame lateral system - amplify always.

2) Concentrically braced, low rise lateral system = maybe don't bother as it won't add up to anything with so little drift.

3) Concentrically braced, high rise lateral system = amplify as there will be significant drift.

 

[TTTKAO]

Thank you for advising KootK.