Portal frame stee

[Anonymous]

Hi,

I have created a portal frame structure with haunches in Robot and have used the program to do steel design. Within the output, the critical moment for the rafters occurs at the location where the rafter meets the column (see 291kNm below). In the steel design calculation output it is stated that the section used for this rafter element at this location is the combined rafter+haunch section, which would be appropriate. What is unclear however, is what section properties have been adopted for the member away from the haunch to accommodate the 109kNm (see screenshot). Could you clarify a way in which to determine where the standard beam section is adopted or the combined section when the steel design is carried out.

Also note the message i am receiving when carrying out steel design, is this relevant?

[Anonymous]

Hi,

I think so. Obviously it is almost irrelevant when you design the structure, but to have a deep look at it, try to create two identical portal frame and in one of them add a huge haunch (ex 2000x2000mm).

Anyway, to check it, go to design results, detail, and check the section properties.

For the warning, I presume it is just telling you that the section properties used for the design are different due to the presence of the haunch.