A designer designed a 5-story, 3 bay building using reinforced concrete frame system. The dimensions and the cross-section details of the beams at the second story of the building are shown in the figure below. The building was designed for an unfactored dead load of 1.5 k/ft (includes the self-weight of the beam) and an unfactored live load of 2.2 k/ft. Check if the beams can support the load. Use the load combination w _u = 1.2D+1.6L to estimate the design load; beams are built integrally with the columns. To estimate the demands due to the loads, you can use ACI simplified Method.

Part b) the owners of the building are planning to change the purpose of the building, which will increase the unfactored live load to 2.5k/ft. Check if the owners need to do additional repairs to the beams?

Material Properties: Concrete Strength = 4500 psi, normal weight concrete;

Grade 60 steel.

Transcribed Image Text:

%23 Wdesd1.5 k/ft Wve 2.2 k/ft %3D Кв в A' 20 ft 20 ft 20 ft #9 bars 17.5" 17.5" 20" 3 #7+2 #5 bars 20 #5 bars 14" 14" Section AA Section BB %23 Wdesd1.5 k/ft Wve 2.2 k/ft %3D Кв в A' 20 ft 20 ft 20 ft #9 bars 17.5" 17.5" 20" 3 #7+2 #5 bars 20 #5 bars 14" 14" Section AA Section BB