Calculation Open Girder

[fabiogardenghi]

Hi everyone,
I have a open box girder, how can I calculate local stress in the open region. Consider all of internal forces (Mx , My , Vx , Vy , N, Mt)in the certer of the girder.
How should I combine the global with local stress?
See attached drawing.
Are there any book that explanation about this topic?
Thanks
Fábio Gardenghi

 

[fancypants]

You might want to take a look at AISC Design Guide 2 "Design of steel and composite beams with web openings".