upper flange fully restraint

[danielrmc1726]

hello iam trying to design a group of beams, this beams will support a concrete slab and i need to consider the top flange fully restrained, but when i add the position of the bracings there is not any change in the effective lenght of the beam, am using AISC 2016 CODE.

i will appreciate any help

thanks!

[Krzysztof_Wasik]

Hi @danielrmc1726 

Member critical point is at its begining. Bottom flange might be compressed in that point.

[danielrmc1726]

the beams are released at ends (simply supported) so the bottom flange is in tension in all the lenght,  that´s why i want to restrain the top flange , correct me if iam wrong.

[Krzysztof_Wasik]

Hi @danielrmc1726 

As far as I can check in your screenshots, Steel design calculation note shows negative My moment. 

according to sign convention in Robot it suggest compression in bottom flange.