Dead Load $=175$psf$,$ Live Load$=50$psf

$$ Objectives of Lesson:

Design the beam elements in a floor system of a steel frame building

Design Problem: $150\text{'}$ by $120\text{'}$ floor $($Design for Bending only, just beams and girders$)$

Floor System:

${120}^{\text{'}}{150}^{\text{'}},$ Columns on a ${30}^{\text{'}}$ Grid

Girders span from Column to column in the $150$ foot direction

Beams span between girders

Concrete floor spans across beams

Loading: See table on following page Elements$/$Materials:

Beams: S$-$Shape

a$.$ Use same beam throughout

b$.$ No deeper than $S12($to limit floor thickness$)$

c$.$ Spacing must be $6^{\text{'}}$ and a factor of ${30}^{\text{'}}($i$.$e$.2^{\text{'}},3^{\text{'}},5^{\text{'}},6^{\text{'}})$

d$.$ Select spacing and S$-$beam that result in the least amount of total steel

Girders: W$-$shape

a$.$ Use same girder throughout

b$.$ Select lightest possible member

c$.$ Approximate load on girder as a distributed load $($rather using multiple point loads from the s$-$beams$).$

Material: Steel

a$.{}_{\text{u}\text{l}\text{t}}=50$ksi

b$.$ F$.$S$.=1\mathrm{.}67$

Expectations

a$.$ Clear presentation of your design. I should be able to see very quickly what you final design is $($beams$,$ beam spacing, girders$).$

Dead Loak $=175$psf Live Load $=50$