12 feet You will be creating a computer model of a 4 span co

12 feet You will be creating a computer model of a 4 span continuous pedestrian bridge. The cross section of the pedestrian bridge is composed of a 5inch thick concrete slab on top of two W18x75 W18x75 full cross section as a single frame section. The cross section area of a W18x75 is 22.0 in?. Determine a) The uniformly distributed Dead load of the full cross section b) The uniformly distributed Live load on the full cross section.

Solution

a) Thickness of slab = 5 in

Unit weight of concrete=150 pcf

Weight ofn concrete=(5/12)*150=62.5 psf

Width of slab = 12 feet

Unifiorm load of slab on full cross section = 12*62.5=750 plf

Self weight of beams = 75*2=150 plf

Total dead load = 750+75=825 plf

b)Live load intensity = 90 psf

uniform live load on full cross section= 90*12=1080 plf