Lumber Storage Shed Configuration
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Top Grade Lumber company needs a new storage shed and have hired you to specify
the longest span of the shed that be constructed using only 2x8 pieces of lumber.
You have decided to use a "T" cross sectional beam by combining two
2x8 pieces of lumber (at the job site).
What is known:
- The roof needs to withstand a combined dead and live load of 60 lb/ft2.
- The 2x8 "T" beams will be spaced 2 ft on center.
- The width of the shed, W, is not given and can be many more beams wide.
- Local building codes require a factor of safety of 2.0.
- The wood is Douglas Fir with a failure stress of 7,500 psi.
- Two 2x8s are securely glued and nailed together (shear stresses
at joint do not have to be considered).
- Assume the beam is simply supported at each end by the wall structure.
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