Different sectrion values in analysis than database

[arailosotenet_gr]

Hi there,

I have a problem when analysing a steel structure using a user defined section. As you can see from the 1st image the Wply and Wplz values in the section database are different from the W values that are considered in the analysis as shown in the 2nd image...Both are for the user-defined MSTT section....

Could you give me a hint of what's going wrong?

I can upload any file you might need....

Thanks a lot.

[Rafal.Gaweda]

Steel design module calculates these values internally for known sections = for which it is known \ code tells us how to calculate  these properties.

In your case you have set SHAPE_TYPE = 36 -> tube

[arailosotenet_gr]

Thanks for your reply.

So is there a shape factor that decreases the Wpl value according to the section type?

This process is refered to EC3 followed by the shape factors?

Lastly, when I save the section in the database is it neccessary to choose a section type and is this section type that I'm choosing the right one?

Many thanks again....

[Rafal.Gaweda]

So is there a shape factor that decreases the Wpl value according to the section type?

This process is refered to EC3 followed by the shape factors?

No, no "factor". Closed = known formula is used to calculate such properties instead of taking them from database

Lastly, when I save the section in the database is it neccessary to choose a section type and is this section type that I'm choosing the right one?

Section type value determines the section shape and the path of design.

It is not neccessary to set it properly if you do not design it in Robot.

In case of steel design you have to set correct shape \ section type number.

If you leave 0 such section acn be also designed using most common approach.