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StructuralEng, Bachelor's Degree
Category: Engineering
Satisfied Customers: 7260
Experience:  Engineering Expert
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Concrete floor span

Customer Question

concrete floor span
Submitted: 1 year ago.
Category: Engineering
Customer: replied 1 year ago.
need to span a concrete floor beam 20ft. that beam will be intersected by another 10ft beam at the mid point. This is to hold up a concrete floor 12x12 ft. Walls will be cmu. Need to know what size and spec these beams need to be.
Customer: replied 1 year ago.
In the attached picture, The red floor beam (C) needs to span 18-20ft. Beam (A) needs to intersect Beam (C) right at half way point and has a support just at about 8ft from the intersection. Beam B is 8ft across. the slab (4"-5") is what i want suspended with cmu wall supporting roof on Beam (A) and the southern section of beam (C).
Expert:  StructuralEng replied 1 year ago.
Hello. I can help
Expert:  StructuralEng replied 1 year ago.
I can design one of the beams for you as this question. Which one would you like?
Expert:  StructuralEng replied 1 year ago.
As an additional service, I can design the beams and slab with all beam width and depth and rebar requirements and concrete strength requirements and sketches. For the slab, too.
Customer: replied 1 year ago.
The longer beam is the most important to me. I can figure out the intersecting beam and the slab. Just need this main beam to be able to hold up that slab and cmu walls.
Expert:  StructuralEng replied 1 year ago.

Are the CMU walls directly above the beam Are they bearing walls?

Customer: replied 1 year ago.
the cmu walls will run on the beam.They will be holding up part of a roof.
Expert:  StructuralEng replied 1 year ago.

I really need to see a roof plan so I can track load to that wall which will, in turn, load the beam.

Customer: replied 1 year ago.
The yellow part is the part is the slab being suspnded. Red lines is floor below.
Customer: replied 1 year ago.
Anything ?
Expert:  StructuralEng replied 1 year ago.
Is this a complete concrete building?
Expert:  StructuralEng replied 1 year ago.
Are you sure the cmu walls are bearing walls? That would be atypical for a concrete slab
Customer: replied 1 year ago.
The cmu walls are holding up the roof. I can simply place a column right under where the two cmu walls meet but want to keep the floor below open. i just need to know what size beam will hold this up.
Customer: replied 1 year ago.
Its complete concrete. see attached for better illustration
Customer: replied 1 year ago.
Any luck?