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Analysis of existing and new framing

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shacked

Structural
Aug 6, 2007
176
I am doing a residential project where there is an existing 2 story house and they are adding a new front balcony.
The existing floor joists cantilever 3.5ft and support the wall (roof) above.

Since this isn't the best condition I am adding a steel beam under the wall above so that I can cantilever new deck joists out for the new balcony. I am extending the new deck joists 7ft back into the existing floor framing and sistering them to the existing floor joists.

I am having problems correctly analyzing the reactions to the new steel beam.
Would the rxn at the new stl beam just be the entire fj/dj span with 3 simply supported rxns?

Partial framing plan attached

Thanks
 
 https://files.engineering.com/getfile.aspx?folder=02ca557e-b23e-4350-9163-bbb2a9d205e1&file=FJDJ.pdf
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Sketch out a quick section of the framing and loading. That should get you your answer.

Also, I'm a little surprised this requires steel.
 
If the framing plan is a jpeg you can add it in-line via the "image" button above the post..... will get more responses that way.
 
beav-eng, I have already sketched it but I am not 100% sure about the reactions.
I initially assumed that the reactions would be the fbd of the entire new & existing joist section with 3 rxn's.

The beam is 18'-6" it supports roof, floor and balcony. 40psf LL & 60psf LL for balcony. A wood bm works but it is 16" deep. Thats why I'm using steel.

Thanks Lex, see attached .jpg. Red is the new framing.
jsts_n5lpk5.jpg
 
Which part are you unsure about? This FBD looks correct based on the plan you provided.
 
Haha, forget I asked....I had a major brain fart.
 
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