EC3 design parameters

[kostastomp]

Hi everyone,

Could somebody please explain to me what do these parameters shown below mean?

The help menu doesn't say much about them.

1) On the first image: If I define a buckling length, or select one of the predefined options, does it make any difference if I say that the member is sway or non sway? When should I use this option?

2) On the second image: Do pipes refer to hollow sections in general, or just round pipes? I am asking becuase further below it distinguishes and asks more specifically for round pipes.  

Also what is this f_yb and f_ya parameter? Any reference to the Eurocode please?

Excuse my basic questions, but I would like to know exactly what the software does and not just use it as a black box.

Regards,

K

[Krzysztof_Wasik · Accepted solution]

Hi @kostastomp 

Ad1 Buckling length coefficient calculation

When sway option is on automatic procedure for buckling length coefficient calculation

allow element horizontal displacement ( frame with no bracing)

In most cases buckling coefficient calculated automatically will be >1

When non-sway option is on, automatic  procedure for buckling length coefficient calculation does not allow element horizontal displacement ( frame with bracings)

In most cases buckling coefficient calculated automatically will be <1

Ad2.

Fyb and Fya refers to cold formed sections, EN-1993-1-3

paragraph  3.2.2 Material properties of cold formed sections and sheeting.

If I managed to answer your question(s) press the Accept as Solution button please. This will help other users to find solution(s) much faster. Thank you.

[paul.bassLH]

Hi,

1) the difference may be illsutrated with these two screenshots.

Non-sway structureSway structure

2) It is not clear. To be honest, i don't know :/. Maybe just to condiser that hot rolled pipe have a yield stress slightly lower than cold formed pipe. Someone else have an idea ?

Regards

[kostastomp]

Thank you both.

Paul, I know what a sway and and non-sway frame is. The fact that the sway-non sway button is not greyed out when selecting one of the standard (non automatic) buckling length settings.